JPH09272901A - Powder molding method - Google Patents
Powder molding methodInfo
- Publication number
- JPH09272901A JPH09272901A JP8514696A JP8514696A JPH09272901A JP H09272901 A JPH09272901 A JP H09272901A JP 8514696 A JP8514696 A JP 8514696A JP 8514696 A JP8514696 A JP 8514696A JP H09272901 A JPH09272901 A JP H09272901A
- Authority
- JP
- Japan
- Prior art keywords
- molding
- powder
- die
- green compact
- lubricant
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Powder Metallurgy (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は粉末を圧縮成形して
圧粉体を得る粉末成形方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder molding method for compressing powder to obtain a green compact.
【０００２】[0002]
【従来の技術】従来より粉末冶金では、ステアリン酸亜
鉛等の潤滑剤が成形用粉末に添加されている。これによ
り成形用粉末の潤滑性が確保されている。また米国特許
公報４，９５５，７９８号には、固体潤滑剤を含有する
粉末冶金用の成形用粉末を用い、その成形用粉末を、常
温以上でかつ固体潤滑剤が溶ける温度以下の温度領域、
つまり７０°C 以上で１５０°C 未満の温度領域、一般
的には７０〜１２０°C の温度領域に加熱し、その加熱
した成形用粉末を用いて、成形型で圧縮成形して圧粉体
を形成する温間粉末成形方法が開示されている。2. Description of the Related Art Conventionally, in powder metallurgy, a lubricant such as zinc stearate has been added to molding powder. This ensures the lubricity of the molding powder. Further, US Pat. No. 4,955,798 uses a molding powder for powder metallurgy containing a solid lubricant, the molding powder having a temperature range not lower than room temperature and not higher than a temperature at which the solid lubricant melts.
That is, it is heated to a temperature range of 70 ° C or higher and lower than 150 ° C, generally 70 to 120 ° C, and the heated molding powder is used to perform compression molding with a molding die to obtain a green compact. There is disclosed a warm powder molding method for forming a.
【０００３】また特開平５−２７１７０９号公報には、
１０〜３０ｗｔ％のＣ10〜Ｃ22であるモノカルボン酸
と、１０〜３０ｗｔ％のＣ10〜Ｃ22であるジカルボン酸
と、４０〜８０ｗｔ％の（ＣＨ2 ）X （ＣＨ2 ）
2 （ｘ：２〜６）であるジアミンとの反応生成物である
高温用潤滑剤を成形用粉末に添加する技術が開示されて
いる。この潤滑剤によれば、３７０°C 以下で粉末冶金
用潤滑剤として使用可能とされている。Further, Japanese Patent Laid-Open No. 5-271709 discloses that
10 to 30 wt% of C 10 to C 22 monocarboxylic acid, 10 to 30 wt% of C 10 to C 22 dicarboxylic acid, and 40 to 80 wt% of (CH 2 ) x (CH 2 ).
A technique for adding a lubricant for high temperature, which is a reaction product of 2 (x: 2-6) to a diamine, to a molding powder is disclosed. According to this lubricant, it can be used as a lubricant for powder metallurgy at 370 ° C or lower.
【０００４】[0004]
【発明が解決しようとする課題】ところで粉末粒子自体
の高密度化を図るには、粉末の加熱温度を高くすれば良
い。しかし成形用粉末を１５０°C 以上に加熱すれば、
成形用粉末に添加されている潤滑剤の流動性が著しく低
下し、高い密度をもつ圧粉体を得ることができない。上
記した米国特許公報４，９５５，７９８号に係る技術に
おいても、１５０°C 未満であれば、成形用粉末の流動
性が確保されるものの、１５０°C 以上に加熱すれば、
潤滑剤が融け、成形用粉末の流動性が著しく低下するた
め、粉箱等を使った粉末充填ができず、連続成形（生産
性）の面で不利である。By the way, in order to increase the density of the powder particles themselves, the heating temperature of the powder may be raised. However, if the molding powder is heated above 150 ° C,
The fluidity of the lubricant added to the molding powder is remarkably reduced, and a green compact having a high density cannot be obtained. Even in the technique according to the above-mentioned US Pat. No. 4,955,798, if the temperature is less than 150 ° C., the fluidity of the molding powder is secured, but if heated to 150 ° C. or higher,
Since the lubricant melts and the fluidity of the molding powder is remarkably reduced, it is not possible to fill the powder using a powder box or the like, which is disadvantageous in terms of continuous molding (productivity).
【０００５】また特開平５−２７１７０９号公報に係る
技術によれば、一般的な潤滑剤に比較して融点が高いた
め３７０°C 以下で使用可能ではあるものの、やはり１
５０°C 以上では、粉末の流動性が低下する。上記した
事情により、従来に係る温間粉末成形方法によれば、粉
末の加熱温度は１５０°C 未満となっていた。According to the technique disclosed in Japanese Unexamined Patent Publication No. 5-271709, although it can be used at 370 ° C. or lower because it has a higher melting point than general lubricants,
Above 50 ° C, the fluidity of the powder decreases. Due to the above-mentioned circumstances, according to the conventional warm powder molding method, the heating temperature of the powder was less than 150 ° C.
【０００６】本発明は上記した実情に鑑みなされたもの
であり、その課題は、圧粉体の密度や強度を向上するの
に有利な粉末成形方法を提供することにある。The present invention has been made in view of the above circumstances, and an object thereof is to provide a powder molding method which is advantageous for improving the density and strength of a green compact.
【０００７】[0007]
【課題を解決するための手段】本発明者は上記課題のも
とに鋭意開発を進め、潤滑剤を実質的に含有しない成形
用粉末を用い、成形用粉末及び成形型の双方を１５０〜
４００°C の温度領域に加熱すると共に、成形型の型面
に潤滑剤を塗布した状態で、成形用粉末を圧縮成形して
圧粉体を成形すれば、圧粉体の密度や強度を向上するの
に有利であることを知見し、本発明方法を開発した。Means for Solving the Problems The inventors of the present invention have made extensive efforts to solve the problems described above, and have used a molding powder that does not substantially contain a lubricant, and have 150-150 g of both the molding powder and the molding die.
The density and strength of the green compact can be improved by heating the powder in the temperature range of 400 ° C and applying the lubricant to the surface of the mold to form the green powder by compression molding. It was found to be advantageous to do so, and the method of the present invention was developed.
【０００８】即ち、本発明に係る粉末成形方法は、成形
キャビティを区画する型面を備えた粉末成形用の成形型
と、潤滑剤を実質的に含有しない成形用粉末とを用い、
成形型及び成形用粉末とを１５０〜４００°C の温度領
域に加熱する加熱操作を行うと共に、成形型の型面に潤
滑剤を塗布する塗布操作とを行う工程と、前記温度領域
に加熱された成形型の成形キャビティに、前記温度領域
に加熱された成形用粉末を装填する工程と、成形キャビ
ティに装填した成形用粉末を圧縮成形して圧粉体とする
工程とを順に行うことを特徴とするものである。That is, the powder molding method according to the present invention uses a powder molding mold having a mold surface for defining a molding cavity and a molding powder containing substantially no lubricant.
The heating operation of heating the molding die and the molding powder to a temperature range of 150 to 400 ° C, and the application operation of applying a lubricant to the die surface of the molding die, and the heating operation to the temperature area are performed. Characterized in that a step of loading the molding powder heated in the temperature range into the molding cavity of the molding die and a step of compressing and molding the molding powder loaded in the molding cavity into a green compact are performed in order. It is what
【０００９】[0009]
【発明の実施の形態】本発明方法で用いる成形型は、成
形キャビティを区画する型面を備えたものであり、一般
的には金型を採用でき、場合によってはセラミックス型
等を採用できる。本発明方法で用いる成形用粉末として
は、潤滑剤を実質的に含有しないものであり、一般的に
は金属粉末を採用できる。従って本発明方法で用いる成
形用粉末には、一般的には、潤滑剤が全く含有されてい
ない。金属粉末の材質としては、従来より公知のもの、
例えば鉄系、Ｎｉ系、銅系、アルミ系等を採用できる。
金属粉末としては噴霧粉、電解粉、還元粉等の公知のも
のを採用できる。BEST MODE FOR CARRYING OUT THE INVENTION The molding die used in the method of the present invention has a molding surface for partitioning a molding cavity. Generally, a mold can be adopted, and in some cases, a ceramic mold or the like can be adopted. As the molding powder used in the method of the present invention, a lubricant is not substantially contained, and a metal powder can be generally adopted. Therefore, the molding powder used in the method of the present invention generally contains no lubricant at all. As the material of the metal powder, conventionally known materials,
For example, iron-based, Ni-based, copper-based, aluminum-based, etc. can be adopted.
As the metal powder, known powder such as spray powder, electrolytic powder, and reduction powder can be adopted.
【００１０】成形用粉末が高温で加熱されると、成形用
粉末の軟化性、成形性が向上するものの、雰囲気が大気
中であれば、成形用粉末の酸化が促進されるおそれがあ
る。また成形用粉末の加熱温度が低温であれば、成形用
粉末の酸化の抑制には有利であるものの、成形用粉末の
軟化性、成形性が低下する。また成形用粉末の粉末粒子
のサイズが小さいと、成形用粉末の比表面積が大きくな
り、成形用粉末が活性化し、酸化し易くなる。When the molding powder is heated at a high temperature, the softening property and the moldability of the molding powder are improved, but the oxidation of the molding powder may be accelerated if the atmosphere is in the air. Further, if the heating temperature of the molding powder is low, it is advantageous for suppressing the oxidation of the molding powder, but the softening property and moldability of the molding powder are deteriorated. Further, when the size of the powder particles of the molding powder is small, the specific surface area of the molding powder is large, and the molding powder is activated and easily oxidized.
【００１１】この様な事情を考慮して、成形用粉末の加
熱温度を決定する。成形用粉末の材質、粉末粒子の粒径
等にも依るが、成形用粉末の加熱温度は、上限値として
は３５０°C 、３００°C 、２５０°C 、２００°C に
でき、下限値としては１７０°C 、２００°C 、２３０
°C にできるが、これに限定されるものではないことは
勿論である。In consideration of such circumstances, the heating temperature of the molding powder is determined. Depending on the material of the molding powder, the particle size of the powder particles, etc., the heating temperature of the molding powder can be set to 350 ° C, 300 ° C, 250 ° C, 200 ° C as the upper limit, and as the lower limit. 170 ° C, 200 ° C, 230
It can be set to ° C, but is not limited to this.
【００１２】また成形型の加熱温度が高温となると、成
形用粉末の成形性が向上するものの、成形型の寿命の点
で不利となる。また成形型の加熱温度が低温であれば、
成形型の寿命の点で有利であるものの、成形用粉末の成
形性が充分でなくなるおそれがある。この様な事情を考
慮して、成形型の加熱温度を決定する。成形型の材質等
にも依るが、成形型の加熱温度は、上限値としては３５
０°C、３００°C 、２５０°C 、２００°C にでき、
下限値としては１７０°C 、２００°C 、２３０°C に
できる。When the heating temperature of the mold is high, the moldability of the molding powder is improved, but it is disadvantageous in terms of the life of the mold. If the heating temperature of the mold is low,
Although it is advantageous in terms of the life of the mold, the moldability of the molding powder may be insufficient. The heating temperature of the molding die is determined in consideration of such circumstances. The upper limit of the heating temperature of the molding die is 35 depending on the material of the molding die.
Can be 0 ° C, 300 ° C, 250 ° C, 200 ° C,
The lower limit can be 170 ° C, 200 ° C and 230 ° C.
【００１３】本発明方法によれば、成形用粉末が鉄系、
成形型が鉄系であれば、上記事情を考慮すると、成形用
粉末及び成形型の加熱温度は１５０〜３００°C 程度が
好ましいが、これに限定されるものではないことは勿論
である。成形用粉末を加熱する形態、成形型を加熱する
形態としては、赤外線加熱、ヒータ加熱、誘導加熱、ジ
ュール熱加熱等を採用できる。According to the method of the present invention, the molding powder is iron-based,
If the molding die is iron-based, considering the above circumstances, the heating temperature of the molding powder and the molding die is preferably about 150 to 300 ° C, but it is not limited to this. Infrared heating, heater heating, induction heating, Joule heating, etc. can be adopted as a mode of heating the molding powder and a mode of heating the molding die.
【００１４】本発明方法によれば、成形型及び成形用粉
末を１５０〜４００°C の温度領域に加熱する。成形型
の加熱温度と、成形用粉末の加熱温度とは実質的に等温
領域でも良いし、或いは異なっていても良い。成形用粉
末の加熱温度が成形型の加熱温度よりも高い場合には、
成形型の寿命を確保しつつ成形用粉末の成形性を確保す
るのに有利であり、ひいては圧粉体の密度確保に有利で
ある。According to the method of the present invention, the mold and the molding powder are heated to a temperature range of 150 to 400 ° C. The heating temperature of the molding die and the heating temperature of the molding powder may be substantially in the isothermal region or may be different. When the heating temperature of the molding powder is higher than the heating temperature of the molding die,
This is advantageous for ensuring the moldability of the molding powder while ensuring the life of the molding die, and thus for ensuring the density of the green compact.
【００１５】また成形型の加熱温度が成形用粉末の加熱
温度よりも高い場合には、成形用粉末の熱が成形型に伝
達されることを抑制できるため、成形用粉末の温度を維
持するのに有利であり、この意味において圧粉体の密度
確保に有利である。特に圧粉体の表層部分の熱が確保さ
れるので、圧粉体の表面温度の維持に有利であり、圧粉
体の表面の緻密化に有利である。Further, when the heating temperature of the molding die is higher than the heating temperature of the molding powder, the heat of the molding powder can be prevented from being transferred to the molding die, so that the temperature of the molding powder is maintained. In this sense, it is advantageous to secure the density of the green compact. In particular, since the heat of the surface layer portion of the green compact is secured, it is advantageous for maintaining the surface temperature of the green compact and is advantageous for densifying the surface of the green compact.
【００１６】成形用粉末の加熱雰囲気としては、成形用
粉末の種類に応じて適宜選択できる。大気中でも良い
し、非酸化性雰囲気でも良い。非酸化性雰囲気としては
減圧雰囲気、真空雰囲気、窒素雰囲気、希ガス雰囲気等
を採用でき、場合によっては還元性雰囲気でも良い。成
形型の加熱雰囲気についても同様である。本発明方法に
よれば、成形型の型面に潤滑剤が塗布される。これによ
り成形用粉末と成形型の型面との摩擦は低減され、成形
用粉末の装填性が向上する。潤滑剤としては公知のもの
を採用でき、固体潤滑剤でも良いし、固体潤滑剤を溶媒
に分散または溶解させたものを採用でき、例えばステア
リン酸亜鉛系、黒鉛系、窒化ボロン系、金属せっけん系
などを採用できる。溶媒としては水、アルコール等を採
用できる。塗布手段としてはスプレー塗布、はけ塗り、
浸漬等の公知の方法を採用できる。The heating atmosphere of the molding powder can be appropriately selected according to the type of the molding powder. It may be in the air or in a non-oxidizing atmosphere. As the non-oxidizing atmosphere, a reduced pressure atmosphere, a vacuum atmosphere, a nitrogen atmosphere, a rare gas atmosphere, or the like can be adopted, and in some cases, a reducing atmosphere may be used. The same applies to the heating atmosphere of the molding die. According to the method of the present invention, the lubricant is applied to the mold surface of the mold. As a result, friction between the molding powder and the mold surface of the molding die is reduced, and the loading property of the molding powder is improved. As the lubricant, a known lubricant can be adopted, a solid lubricant may be used, or a solid lubricant dispersed or dissolved in a solvent can be adopted, for example, zinc stearate-based, graphite-based, boron nitride-based, metal soap-based Can be adopted. Water, alcohol, etc. can be adopted as the solvent. As a coating means, spray coating, brush coating,
A known method such as dipping can be adopted.
【００１７】本発明方法によれば、成形型及び成形用粉
末を１５０〜４００°C の温度領域に加熱する加熱操作
と、成形型の型面に潤滑剤を塗布する塗布操作とが行わ
れる。この場合には、加熱操作の後に塗布操作が行われ
ても良いし、或いは、塗布操作の後に加熱操作が行われ
ても良いし、或いは、加熱操作と塗布操作とが時間的に
同時に行われても良い。According to the method of the present invention, a heating operation of heating the molding die and the molding powder to a temperature range of 150 to 400 ° C. and a coating operation of applying a lubricant to the molding surface of the molding die are performed. In this case, the coating operation may be performed after the heating operation, or the heating operation may be performed after the coating operation, or the heating operation and the coating operation are performed simultaneously in time. May be.
【００１８】[0018]
【実施例】以下、本発明に係る実施例について説明す
る。まず説明の便宜上、図１を参照して成形型１から説
明する。成形型１は、ダイス孔をもち固定型として機能
するリング状をなす金属製のダイス型１１と、ダイス型
１１の外周部を保持するリング状をなす金属製のダイス
ホルダ１２と、ダイス型１１に対して昇降可能な金属製
の上パンチ型１３と、ダイス型１１のダイス孔に嵌合さ
れた金属製の下パンチ型１４とを備えている。下パンチ
型１４は基部１５に保持されている。Embodiments of the present invention will be described below. First, for convenience of description, the mold 1 will be described with reference to FIG. The molding die 1 includes a ring-shaped metal die die 11 that has a die hole and functions as a fixed die, a ring-shaped metal die holder 12 that holds an outer peripheral portion of the die die 11, and a die die 11. On the other hand, a metal upper punch die 13 that can be raised and lowered and a metal lower punch die 14 that is fitted in the die holes of the die die 11 are provided. The lower punch die 14 is held by the base portion 15.
【００１９】ダイス型１１のダイス孔の型面、下パンチ
型１４の型面、上パンチ型１３の型面により、成形キャ
ビティ１７が区画される。上パンチ型１３には、これを
加熱する第１ヒータ１３ｃが装備されている。ダイス型
１１には、これを加熱する第２ヒータ１１ｃが装備され
ている。更にダイスホルダ１２及びダイス型１１の上方
をガイド２ｘに沿って移動可能な可動式の粉箱２が装備
されている。粉箱２は、成形用粉末を収容する収容室２
ｅをもつ。収容室２ｅは、上面開口２ｈ及び下面開口２
ｋをもつ。粉箱２には、潤滑剤を噴霧するためのスプレ
ーノズル３がアーム３ｍを介して装備されている。粉箱
２には、収容室２ｅ内の成形用粉末Ｐを加熱する第３ヒ
ータ２ｃが装備されている。The molding cavity 17 is defined by the die surface of the die die 11, the die punching surface of the lower punch die 14, and the die punching surface of the upper punch die 13. The upper punch die 13 is equipped with a first heater 13c for heating the upper punch die 13. The die die 11 is equipped with a second heater 11c for heating the die die 11. Further, a movable powder box 2 which is movable above the die holder 12 and the die die 11 along the guide 2x is provided. The powder box 2 is a storage chamber 2 for storing the molding powder.
with e. The accommodation chamber 2e has an upper surface opening 2h and a lower surface opening 2
has k. The powder box 2 is equipped with a spray nozzle 3 for spraying a lubricant via an arm 3m. The powder box 2 is equipped with a third heater 2c for heating the molding powder P in the storage chamber 2e.
【００２０】また成形型１の近傍には粉末供給装置７が
設けられている。粉末供給装置７は、成形用粉末Ｐを収
容する粉末容器７０と、粉末容器７０から下方に延設さ
れ待機中の粉箱２の収容室２ｅに臨む送給路７１と、送
給路７１を開閉する弁７２と、送給路７１内の成形用粉
末Ｐを加熱する第４ヒータ７３とをもつ。第１ヒータ１
３ｃ、第２ヒータ１１ｃ、第３ヒータ２ｃ、第４ヒータ
７３は図略の温度制御装置により制御され、それぞれの
目標加熱温度に維持される。A powder supply device 7 is provided near the molding die 1. The powder supply device 7 includes a powder container 70 for containing the molding powder P, a feeding path 71 extending downward from the powder container 70 and facing the storage chamber 2e of the powder box 2 on standby, and a feeding path 71. It has a valve 72 that opens and closes, and a fourth heater 73 that heats the molding powder P in the feeding passage 71. First heater 1
3c, the second heater 11c, the third heater 2c, and the fourth heater 73 are controlled by a temperature control device (not shown), and are maintained at their respective target heating temperatures.
【００２１】さて本実施例によれば使用の際には、第２
ヒータ１１ｃによりダイス型１１が所定の温度領域に加
熱されている。第１ヒータ１３ｃにより上パンチ型１３
が所定の温度領域に加熱されている。粉末供給装置７の
第４ヒータ７３により粉末容器７０の成形用粉末Ｐは所
定の温度領域に加熱されている。本実施例によれば、成
形型１の目標加熱温度は１５０〜４００°C のうちの所
定の温度領域である。成形用粉末Ｐの目標加熱温度は１
５０〜４００°C のうちの所定の温度領域である。Now, according to this embodiment, when using, the second
The die 11 is heated to a predetermined temperature range by the heater 11c. The upper punch die 13 by the first heater 13c
Are heated to a predetermined temperature range. The molding heater P of the powder container 70 is heated to a predetermined temperature range by the fourth heater 73 of the powder supply device 7. According to this embodiment, the target heating temperature of the molding die 1 is within a predetermined temperature range of 150 to 400 ° C. The target heating temperature of the molding powder P is 1
It is a predetermined temperature range of 50 to 400 ° C.
【００２２】図１に示すように、成形キャビティ１７か
ら離れた待機位置Ｍに、粉箱２が待機している。粉末供
給装置７の弁７２が開放すると、加熱された成形用粉末
Ｐが粉末供給装置７から自然落下して粉箱２の収容室２
ｅに送給される。粉箱２の収容室２ｅ内の成形用粉末
は、第３ヒータ２ｃにより加熱され、所定の温度領域に
維持された状態で収容室２ｅ内で待機している。As shown in FIG. 1, the powder box 2 stands by at the stand-by position M separated from the molding cavity 17. When the valve 72 of the powder supply device 7 is opened, the heated molding powder P naturally drops from the powder supply device 7 and the storage chamber 2 of the powder box 2 is closed.
sent to e. The molding powder in the storage chamber 2e of the powder box 2 is heated by the third heater 2c and is kept in the storage chamber 2e while being maintained in a predetermined temperature range.
【００２３】所定の時刻になると、図２（Ａ）に示すよ
うに粉箱２がシリンダ２ｐにより矢印Ｘ１方向に移動す
る。よって図２（Ｂ）に示すようにスプレーノズル３が
成形キャビティ１７及び上パンチ型１３に対面し、その
位置で粉箱２が停止する。この状態で、スプレーノズル
３が作動して、スプレーノズル３から潤滑剤Ｌが上下方
向に噴霧される。これによりダイス型１１の型面、下パ
ンチ型１４の型面、上パンチ型１３の型面にそれぞれ、
潤滑剤Ｌが塗布される。つまり成形型１の型面に潤滑剤
Ｌを塗布する『型潤滑』操作が実行される。At a predetermined time, as shown in FIG. 2 (A), the powder box 2 moves in the direction of arrow X1 by the cylinder 2p. Therefore, as shown in FIG. 2B, the spray nozzle 3 faces the molding cavity 17 and the upper punch die 13, and the powder box 2 stops at that position. In this state, the spray nozzle 3 operates, and the lubricant L is sprayed vertically from the spray nozzle 3. As a result, the die surface of the die die 11, the die surface of the lower punch die 14, and the die surface of the upper punch die 13 are respectively
Lubricant L is applied. That is, the “die lubrication” operation of applying the lubricant L to the die surface of the forming die 1 is executed.
【００２４】本実施例によれば、ダイス型１１や上パン
チ型１３は高温状態に加熱されているため、これらの熱
で液状の潤滑剤Ｌは速やかに乾燥する。よって、潤滑膜
がダイス型１１の型面、下パンチ型１４の型面、上パン
チ型１３の型面にそれぞれ積層される。従って、液状の
潤滑剤Ｌを乾燥させる乾燥操作を廃止または簡略化する
のに有利であり、生産能率の向上に貢献できる。According to the present embodiment, since the die die 11 and the upper punch die 13 are heated to a high temperature state, the liquid lubricant L is quickly dried by these heats. Therefore, the lubricating film is laminated on the die surface of the die die 11, the die surface of the lower punch die 14 and the die surface of the upper punch die 13, respectively. Therefore, it is advantageous to abolish or simplify the drying operation for drying the liquid lubricant L, which can contribute to the improvement of production efficiency.
【００２５】『型潤滑』操作による塗布が終了すると、
粉箱２が矢印Ｘ１方向に更に移動し、図２（Ｃ）に示す
ように、粉箱２の収容室２ｅの下面開口２ｋが成形キャ
ビティ１７に対面する。すると粉箱２の収容室２ｅの成
形用粉末Ｐは、重力により自然落下して成形キャビティ
１７に装填される。装填が完了したら、粉箱２は矢印Ｘ
２方向に移動して待機位置Ｍに戻る。その後、上パンチ
型１３が矢印Ｙ１方向に下降して成形キャビティ１７に
押入される。よって、成形キャビティ１７内の成形用粉
末Ｐが圧縮成形され、圧粉体が成形される。When the application by the "mold lubrication" operation is completed,
The powder box 2 further moves in the direction of the arrow X1, and the lower surface opening 2k of the storage chamber 2e of the powder box 2 faces the molding cavity 17, as shown in FIG. Then, the molding powder P in the storage chamber 2e of the powder box 2 is naturally dropped by gravity and loaded into the molding cavity 17. When loading is complete, the powder box 2 will show an arrow X
It moves in two directions and returns to the standby position M. After that, the upper punch die 13 descends in the arrow Y1 direction and is pushed into the molding cavity 17. Therefore, the molding powder P in the molding cavity 17 is compression-molded, and the green compact is molded.
【００２６】本実施例によれば、成形キャビティ１７内
の成形用粉末Ｐと成形型１の型面との摩擦は、上記した
潤滑膜により低減され、これにより成形用粉末Ｐの装填
性、圧縮成形性が向上する。上記のように圧粉体が成形
されたら、次に、その圧粉体を焼結温度域に加熱して焼
結体とする焼結工程、焼結体を鍛造型で熱間鍛造して焼
結鍛造体とする鍛造工程が実施される。According to the present embodiment, the friction between the molding powder P in the molding cavity 17 and the mold surface of the molding die 1 is reduced by the above-mentioned lubricating film, whereby the loadability and compression of the molding powder P are reduced. Moldability is improved. Once the green compact has been molded as described above, then the green compact is heated in the sintering temperature range to form a sintered body, and the sintered body is hot forged by a forging die and fired. A forging process for forming a forged body is performed.
【００２７】本実施例によれば、成形用粉末Ｐや成形型
１を加熱する際には、成形用粉末Ｐの加熱温度と成形型
１の加熱温度とが実質的に同一の形態でも良い。また成
形用粉末Ｐの加熱温度が成形型１の加熱温度よりも高い
形態でも良い。また成形型１の加熱温度が成形用粉末Ｐ
の加熱温度よりも高い形態でも良い。成形用粉末Ｐの加
熱温度が成形型１の加熱温度よりも高い場合には、成形
用粉末Ｐの成形性を確保するのに有利である。ひいては
圧粉体の密度確保に有利である。According to the present embodiment, when heating the molding powder P and the molding die 1, the heating temperature of the molding powder P and the heating temperature of the molding die 1 may be substantially the same. Further, the heating temperature of the molding powder P may be higher than that of the molding die 1. Further, the heating temperature of the molding die 1 is the molding powder P.
It may be in a form higher than the heating temperature. When the heating temperature of the molding powder P is higher than the heating temperature of the molding die 1, it is advantageous to ensure the moldability of the molding powder P. As a result, it is advantageous for securing the density of the green compact.
【００２８】成形型１の加熱温度が成形用粉末Ｐの加熱
温度よりも高い場合には、成形用粉末Ｐが成形型１の型
面に接触しても、成形用粉末Ｐの熱が成形型１に逃げる
ことが抑制されるため、成形用粉末Ｐの温度を維持する
のに有利であり、この意味において圧粉体の密度確保に
有利である。特に成形型１の型面に接触する圧粉体の表
層部分の温度が確保されるので、圧粉体の表面温度の維
持に有利であり、表面ポアの低減、回避に有利である。When the heating temperature of the molding die 1 is higher than the heating temperature of the molding powder P, even if the molding powder P comes into contact with the molding surface of the molding die 1, the heat of the molding powder P is generated. Since it is suppressed to escape to 1, it is advantageous to maintain the temperature of the molding powder P, and in this sense, it is advantageous to secure the density of the green compact. In particular, since the temperature of the surface layer portion of the green compact that contacts the mold surface of the molding die 1 is secured, it is advantageous for maintaining the surface temperature of the green compact, and is advantageous for reducing and avoiding the surface pores.
【００２９】なお上記した例では、潤滑剤Ｌを噴霧塗布
する塗布操作、粉箱２の成形用粉末Ｐを自然落下により
成形キャビティ１７に装填する装填操作は、粉箱２を停
止させて行っているが、これに限らず、粉箱２を停止せ
ずに低速で連続的に移動させることにより上記塗布操作
や装填操作を行うことにしても良い。また上記した実施
例では、圧粉体を焼結した焼結体を鍛造する鍛造工程が
実施されるが、これに限らず、圧粉体の用途等によって
は鍛造工程は省略することもできる。In the above example, the coating operation for spray-coating the lubricant L and the loading operation for loading the molding powder P in the powder box 2 into the molding cavity 17 by spontaneously dropping are performed with the powder box 2 stopped. However, the present invention is not limited to this, and the coating operation and the loading operation may be performed by continuously moving the powder box 2 at a low speed without stopping. Further, in the above-described embodiment, the forging step of forging the sintered body obtained by sintering the green compact is performed, but the present invention is not limited to this, and the forging step may be omitted depending on the application of the green compact and the like.
【００３０】また図３に示す例のようにしても良い。即
ち、粉箱２の収容室２ｅの上面開口２ｈを開閉する開閉
蓋２ｒ、及び、下面開口２ｋを開閉する開閉蓋２ｓを設
けると共に、収容室２ｅを減圧装置９に減圧路９ｎ及び
開閉弁９ｖを介して接続することにしても良い。減圧路
９ｎとして、ゴムホースや蛇腹管等のように伸長可能ま
たは屈曲可能な可撓管を採用すれば、粉箱２の移動に対
応できる。減圧装置９としては例えば真空ポンプを採用
できる。Alternatively, the example shown in FIG. 3 may be used. That is, the opening / closing lid 2r for opening / closing the upper surface opening 2h of the storage chamber 2e of the powder box 2 and the opening / closing lid 2s for opening / closing the lower surface opening 2k are provided, and the storage chamber 2e is provided in the pressure reducing device 9 as the pressure reducing passage 9n and the opening / closing valve 9v. You may decide to connect via. If a flexible tube that can be extended or bent, such as a rubber hose or a bellows tube, is adopted as the decompression path 9n, the powder box 2 can be moved. As the decompression device 9, for example, a vacuum pump can be adopted.
【００３１】そして収容室２ｅ内の成形用粉末を第３ヒ
ータ２ｃで加熱しつつ、減圧装置９で収容室２ｅを減圧
状態または真空状態とし、この状態で待機する。待機時
間が終了したら、粉箱２が矢印Ｘ１方向に移動すると共
に、粉箱２が所定の位置に到達したら、開閉蓋２ｒ及び
開閉蓋２ｓが開放して、場合によっては開閉蓋２ｓのみ
が開放するだけで、粉箱２内の成形用粉末Ｐは成形キャ
ビティ１７に落下する。これによれば、待機中において
収容室２ｅ内は減圧状態または真空状態とされているた
め、高温の成形用粉末Ｐの酸化を抑制するのに有利であ
る。While the molding powder in the storage chamber 2e is being heated by the third heater 2c, the storage chamber 2e is depressurized or evacuated by the depressurizing device 9, and the system stands by in this state. When the waiting time ends, the powder box 2 moves in the direction of the arrow X1, and when the powder box 2 reaches a predetermined position, the open / close lid 2r and the open / close lid 2s open, and in some cases only the open / close lid 2s opens. Then, the molding powder P in the powder box 2 falls into the molding cavity 17. According to this, since the inside of the storage chamber 2e is in a depressurized state or a vacuum state during standby, it is advantageous to suppress the oxidation of the high-temperature molding powder P.
【００３２】このように成形用粉末Ｐの酸化抑制に有利
であるため、成形用粉末Ｐの加熱温度を一層高くするの
に有利であり、ひいては圧粉体の一層の高密度化に貢献
でき、圧粉体や焼結体や焼結鍛造体の品質確保に貢献で
きる。更に図３に示すように、粉末供給装置７の粉末容
器７０にこれを開閉する開閉蓋７０ｓを設けると共に、
粉末容器７０を減圧装置９に減圧路９ｍ及び開閉弁９ｗ
を介して接続しても良い。この場合には、粉末容器７０
内の高温の成形用粉末の酸化を抑えるのに有利である。As described above, since it is advantageous to suppress the oxidation of the molding powder P, it is advantageous to further increase the heating temperature of the molding powder P, which in turn contributes to higher density of the green compact. It can contribute to ensuring the quality of green compacts, sintered bodies and sintered forged bodies. Further, as shown in FIG. 3, an opening / closing lid 70s for opening and closing the powder container 70 of the powder supply device 7 is provided,
The powder container 70 is placed in the decompression device 9 and the decompression passage 9m and the open / close valve 9w
You may connect via. In this case, the powder container 70
It is advantageous for suppressing the oxidation of the high temperature molding powder therein.
【００３３】（試験例）本発明方法の効果を確認するた
めに次の試験を行った。 （試験例１） この試験によれば、鉄系粉末と黒鉛粉末とを混合した
成形用粉末を用い、圧粉体を成形する成形面圧を実施例
及び比較例共に７ ton/cm 2 と同一値に設定している。
そして、実施例及び比較例に係る圧粉体を形成し、各圧
粉体の密度を測定した。密度の測定は、日本粉末冶金工
業会規格（JPMA M 01-1992) に基づいた。なお成形用粉
末における黒鉛粉末の割合は、実施例及び比較例共に、
重量比で５％である。(Test Example) The following test was conducted to confirm the effect of the method of the present invention. (Test Example 1) According to this test, the molding surface pressure for molding the green compact was 7 ton / cm 2 in both the practical example and the comparative example by using the molding powder in which the iron-based powder and the graphite powder were mixed. It is set to a value.
And the green compact which concerns on an Example and a comparative example was formed, and the density of each green compact was measured. The density was measured based on the Japan Powder Metallurgical Industry Association Standard (JPMA M 01-1992). The ratio of the graphite powder in the molding powder, in both Examples and Comparative Examples,
It is 5% by weight.
【００３４】鉄系粉末としては実施例及び比較例ともに
同種のもの、つまり商品名：Distaloy AE ( ヘガネス
社）を採用している。Distaloy AE の目標組成は、重量
比で、Ｆｅ−４％Ｎｉ−１．５％Ｃｕ−０．５％Ｍｏで
ある。Distaloyの粒度分布は、１５０μｍ以上が８％、
４５μｍ以下が２０％、４５〜１５０μｍが残部であ
る。As the iron-based powder, the same type of iron-based powder is used in the examples and comparative examples, that is, the trade name: Distaloy AE (Heganes). The target composition of Distaloy AE is, by weight ratio, Fe-4% Ni-1.5% Cu-0.5% Mo. The particle size distribution of Distaloy is 8% above 150 μm,
20% is 45 μm or less and 45-150 μm is the rest.
【００３５】実施例１によれば、潤滑剤が添加されてい
ない上記した成形用粉末を用い、型潤滑すると共に、成
形温度を１５０°C とした状態で、つまり成形用粉末及
び成形型の双方の目標温度を１５０°C とした状態で、
圧粉体を成形した。実施例２によれば、潤滑剤が添加さ
れていない上記した成形用粉末を用い、前述同様に型潤
滑すると共に、成形温度を１８０°C とした状態で、つ
まり成形用粉末及び成形型の双方の温度を１８０°C と
した状態で、圧粉体を成形した。According to Example 1, the above-mentioned molding powder to which the lubricant was not added was used, the mold was lubricated, and the molding temperature was 150 ° C., that is, both the molding powder and the molding die were used. With the target temperature of 150 ° C,
A green compact was molded. According to Example 2, using the above-mentioned molding powder to which no lubricant was added, the mold was lubricated in the same manner as described above, and the molding temperature was 180 ° C., that is, both the molding powder and the molding die were used. The green compact was molded at a temperature of 180 ° C.
【００３６】比較例１によれば、潤滑剤としてステアリ
ン酸亜鉛を上記鉄系粉末に添加した成形用粉末を用い、
成形温度を室温に維持した状態、つまり成形用粉末及び
成形型の双方の温度を室温に維持した状態で圧粉体を成
形した。比較例１によれば、成形用粉末を１００％とし
たときステアリン酸亜鉛は０．５％添加した。比較例２
によれば、温間成形用潤滑剤（米国特許４９５５７９８
に係る潤滑剤）を上記鉄系粉末に添加した成形用粉末を
用い、成形温度を１５０°C とした状態で、つまり成形
用粉末及び成形型の双方の温度を１５０°C にした状態
で圧粉体を成形した。比較例１によれば、成形用粉末を
１００％としたとき温間成形用潤滑剤は０．５％添加し
た。According to Comparative Example 1, a molding powder prepared by adding zinc stearate to the iron-based powder as a lubricant is used.
A green compact was molded while the molding temperature was maintained at room temperature, that is, the temperatures of both the molding powder and the molding die were maintained at room temperature. According to Comparative Example 1, 0.5% of zinc stearate was added when the molding powder was 100%. Comparative Example 2
According to US Pat. No. 4,955,798.
(Lubricant according to 1.) was added to the iron-based powder, and pressure was applied at a molding temperature of 150 ° C, that is, at a temperature of both the molding powder and the mold of 150 ° C. The powder was molded. According to Comparative Example 1, 0.5% of the warm molding lubricant was added when the molding powder was 100%.
【００３７】[0037]
【表１】 圧粉体の密度測定の試験結果は図４に示されている。図
４から理解できるように、成形面圧が同一であっても、
比較例１、２では圧粉体の密度が低いものの、実施例
１、２では高密度の圧粉体が得られる。特に成形温度が
１８０°C である実施例２によれば、圧粉体密度が最も
高い。従って本実施例方法によれば、圧粉体を得る際の
成形面圧が同一（＝７ ton/cm 2 ）であっても、圧粉体
の密度を増加できることがわかる。その理由は、潤滑剤
がないため気孔の緻密化が良好であるためと推察され
る。[Table 1] The test result of the density measurement of the green compact is shown in FIG. As can be seen from FIG. 4, even if the molding surface pressure is the same,
Although the density of the green compact is low in Comparative Examples 1 and 2, high density green compacts are obtained in Examples 1 and 2. Particularly, according to Example 2 in which the molding temperature is 180 ° C., the green compact density is the highest. Therefore, according to the method of this example, it is understood that the density of the green compact can be increased even if the molding surface pressure when obtaining the green compact is the same (= 7 ton / cm 2 ). It is presumed that the reason is that there is no lubricant and the pores are densified well.
【００３８】更に圧粉体の密度を７．１〔g/cm3 〕に
設定したときにおける実施例及び比較例に係る圧粉体の
抗折強度を測定した。抗折強度の測定は、日本粉末冶金
工業会規格（JPMA M 09-1992) に基づいた。試験結果を
図５に示す。図５から理解できるように、比較例１、２
では圧粉体の強度が低いものの、実施例１では高強度つ
まり３〔ｋｇ／ｃｍ2 〕を越える強度の圧粉体が得られ
た。従って本実施例方法によれば、圧粉体密度が同一で
あっても、圧粉体の強度を増加できることがわかる。そ
の理由は、潤滑剤がないため粉末粒子間の固着（粉のか
らみあい）がより強固になるものと推察されている。Further, the bending strength of the green compacts according to the examples and comparative examples when the density of the green compact was set to 7.1 [g / cm 3 ] was measured. The measurement of the bending strength was based on the Japan Powder Metallurgy Association Standard (JPMA M 09-1992). The test results are shown in FIG. As can be understood from FIG. 5, Comparative Examples 1 and 2
In Example 1, although the strength of the green compact was low, a high strength, that is, a green compact having a strength exceeding 3 [kg / cm 2 ] was obtained. Therefore, according to the method of this example, it is understood that the strength of the green compact can be increased even if the green compact density is the same. The reason for this is presumed to be that the adhesion between the powder particles (powder entanglement) becomes stronger because there is no lubricant.
【００３９】（試験例２） この試験によれば、実施例及び比較例共に、鉄系粉末
と黒鉛粉末とを混合した成形用粉末を圧縮成形して圧粉
体を成形する際の成形面圧を５ ton/cm 2 、６ ton/cm
2 、７ ton/cm 2 と変更して成形したとき、圧粉体の密
度変化を調べた。密度の測定は前述同様に、日本粉末冶
金工業会規格（JPMA M 01-1992) に基づいた。なお成形
用粉末における黒鉛粉末の割合は、前述同様に実施例及
び比較例共に、重量比で５％である。Test Example 2 According to this test, in both the example and the comparative example, the molding surface pressure when the molding powder in which the iron-based powder and the graphite powder are mixed is compression-molded to form the green compact. 5 ton / cm 2 , 6 ton / cm
A change in the density of the green compact was examined when molding was performed while changing the pressure to 2 to 7 ton / cm 2 . The measurement of the density was based on the Japan Powder Metallurgical Industry Association standard (JPMA M 01-1992) as described above. The proportion of graphite powder in the molding powder is 5% by weight in both the examples and comparative examples, as described above.
【００４０】実施例Ａによれば、鉄系粉末として前述の
Distaloy AE （ヘガネス社）を採用し、粉末及び成形型
の双方の目標温度を共に１５０°C とした。Distaloy A
E の目標組成は前述したように、重量比で、Ｆｅ−４％
Ｎｉ−１．５％Ｃｕ−０．５％Ｍｏである。実施例Ａに
よれば、測定結果を図６に示す。図６の横軸は成形面圧
を示し、縦軸は圧粉体の密度を示す。図６においてＲＴ
は室温を意味する。According to Example A, the above-mentioned iron-based powder was used.
Distaloy AE (Heganes) was used and the target temperature of both powder and mold was set to 150 ° C. Distaloy A
The target composition of E is, by weight ratio, Fe-4% as described above.
Ni-1.5% Cu-0.5% Mo. According to Example A, the measurement results are shown in FIG. The horizontal axis of FIG. 6 represents the molding surface pressure, and the vertical axis represents the density of the green compact. RT in FIG.
Means room temperature.
【００４１】比較例Ｂによれば、鉄系粉末としてDistal
oy AE （ヘガネス社）を用い、粉末及び成形型の温度を
共に室温としている。比較例Ｃでは、鉄系粉末としてス
テアリン酸亜鉛を添加したDistaloy AE （ヘガネス社）
を用い、成形用粉末及び成形型の温度を共に室温として
いる。 比較例Ｄによれば、ステアリン酸亜鉛に代えて
高温領域でも溶融しない高温用潤滑剤を添加したAncord
ense（ヘガネス社）を鉄系粉末として用い、粉末及び成
形型の温度を共に室温としている。According to Comparative Example B, as an iron-based powder, Distal
oy AE (Heganes) is used, and the temperature of the powder and the mold are both room temperature. In Comparative Example C, Distaloy AE (Heganes Corporation) to which zinc stearate was added as an iron-based powder
And the temperature of the molding powder and the molding die are both room temperature. According to Comparative Example D, instead of zinc stearate, Ancord in which a high temperature lubricant that does not melt even in a high temperature region is added
ense (Heganes) is used as an iron-based powder, and the temperature of the powder and the mold are both room temperature.
【００４２】比較例Ｅによれば、Ancordenseを鉄系粉末
として用い、粉末及び成形型の温度を共に室温としてい
る。図６から理解できるように、粉末及び成形型の双方
が室温領域で圧粉体を成形した比較例Ｃ、比較例Ｄ、比
較例Ｂによれば、圧粉体の密度が低い。また成形用粉末
に高温用潤滑剤が添加されている比較例Ｅによれば、成
形面圧が５〔ton/cm 2 〕〜６〔ton/cm2 〕では圧粉体の
密度が高いものの、成形面圧が７〔ton/cm2〕に近づく
と、密度向上効果は飽和状態に近くなっている。According to Comparative Example E, Ancordense is an iron-based powder.
The temperature of the powder and the mold should both be room temperature.
You. As can be seen from FIG. 6, both powder and mold
Comparative Example C, Comparative Example D, and
According to Comparative Example B, the density of the green compact is low. Molding powder
According to Comparative Example E in which the lubricant for high temperature is added to
Form pressure is 5 [ton / cm Two] ~ 6 [ton / cmTwo] In the
Although the density is high, the molding surface pressure is 7 [ton / cmTwo]
And, the density improving effect is close to the saturated state.
【００４３】これに対して粉末及び成形型の双方の目標
温度が１５０°C である実施例Ａによれば、成形面圧が
７〔ton/cm2 〕となっても、密度向上効果は飽和状態で
はない。すなわち図６から理解できる様に実施例Ａによ
れば、成形面圧が７〔ton/cm 2 〕あれば、密度は比較例
Ｅに係る密度よりも高い。その理由は、成形面圧を高く
したとしても、潤滑剤を含む場合には、潤滑剤に相当す
るぶんは金属粉末が実質的に装填されず、実質的に空孔
とされ、高密度の圧粉体が得られないものの、潤滑剤が
無ければ、そのような不具合がないためであると推察さ
れる。 また上記した実施例Ａ〜比較例Ｅに係る圧粉体につい
て、抗折強度を調べる試験を行った。抗折強度の測定
は、日本粉末冶金工業会規格（JPMA M 09-1992) に基づ
いた。試験結果を図７に示す。図７は横軸が圧粉体の密
度を示し、縦軸が圧粉体の強度を示す。実施例Ａによれ
ば、圧粉体の密度が７．１〔ｇ／ｃｍ3 〕〜７．３〔ｇ
／ｃｍ3 〕〜と高くなれば、圧粉体の強度も３〔ｋｇｆ
／ｍｍ2 〕付近〜４．７〔ｋｇｆ／ｍｍ2 〕付近へと向
上する。即ち実施例Ａによれば、特性線の上昇勾配は大
きい。On the other hand, both powder and mold targets
According to Example A in which the temperature is 150 ° C, the molding surface pressure is
7 [ton / cmTwo], The density improvement effect is saturated
There is no. That is, according to Example A, as can be understood from FIG.
If so, the molding surface pressure is 7 [ton / cm Two] If yes, the density is a comparative example
Higher than the density for E. The reason is that the molding surface pressure is high
Even if you do so, if it contains a lubricant, it is equivalent to a lubricant.
It is probably not filled with metal powder and
Therefore, although a high-density green compact cannot be obtained, the lubricant
If there isn't, it's probably because there is no such defect.
It is. In addition, the green compacts according to the above-mentioned Examples A to E
Then, a test for examining the bending strength was conducted. Measurement of bending strength
Is based on the Japan Powder Metallurgy Association Standard (JPMA M 09-1992).
Was. The test results are shown in FIG. In Fig. 7, the horizontal axis is the density of the green compact.
And the vertical axis represents the strength of the green compact. According to Example A
For example, the density of the green compact is 7.1 [g / cmThree] -7.3 [g
/ CmThree], The strength of the green compact becomes 3 [kgf
/ MmTwo] Near to 4.7 [kgf / mmTwo] Towards the vicinity
Up. That is, according to Example A, the rising slope of the characteristic line is large.
Kii.
【００４４】しかし比較例Ｅによれば、圧粉体の密度が
７．１〔ｇ／ｃｍ3 〕〜７．３〔ｇ／ｃｍ3 〕〜と高く
なったとしても、圧粉体の強度は２．５〔ｋｇｆ／ｍｍ
2 〕付近からあまり向上していない。即ち比較例Ｅによ
れば、特性線の上昇勾配は小さい。 ところで使用の際には、上記した圧粉体は、焼結され
て焼結体とされる。更に密度を高めるために、焼結後に
鍛造で強圧して焼結鍛造体とすることが好ましい。この
場合実際の操業では、焼結体を焼結工程から鍛造工程に
移送する必要があるため、移送中に焼結体は大気に触れ
る。大気に触れる度合いが高い状態の焼結体が鍛造され
ると、焼結鍛造体に表面欠陥が発生し、焼結鍛造体の強
度確保のために不利であることは既に知られている。However, according to Comparative Example E, even if the density of the green compact is as high as 7.1 [g / cm 3 ] to 7.3 [g / cm 3 ], the strength of the green compact is 2.5 [kgf / mm
2 ] Not much improved from the vicinity. That is, according to the comparative example E, the rising gradient of the characteristic line is small. By the way, in use, the above-mentioned green compact is sintered into a sintered body. In order to further increase the density, it is preferable that a strong pressure is applied by forging after sintering to obtain a sintered forged body. In this case, in the actual operation, it is necessary to transfer the sintered body from the sintering step to the forging step, so the sintered body is exposed to the atmosphere during the transfer. It is already known that when a sintered body that is exposed to the atmosphere is forged, surface defects occur in the sintered forged body, which is disadvantageous for securing the strength of the sintered forged body.
【００４５】そこでこの試験では、上記した圧粉体を焼
結温度域（１１２０〜１１５０°C）で焼結して焼結体
を形成し、その焼結体を大気に所定時間Ｔ（Ｔ＝１０秒
間）露出し、その後に、その焼結体を熱間鍛造して焼結
鍛造体とした。そして焼結鍛造体の表面欠陥の面積率を
測定し、圧粉体の密度ρをパラメータとして、図８に示
した。Therefore, in this test, the above-mentioned green compact is sintered in a sintering temperature range (1120 to 1150 ° C.) to form a sintered body, and the sintered body is exposed to the atmosphere for a predetermined time T (T = T = T). It was exposed for 10 seconds, and then the sintered body was hot forged to obtain a sintered forged body. Then, the area ratio of surface defects of the sintered forged body was measured and shown in FIG. 8 using the density ρ of the green compact as a parameter.
【００４６】図８は横軸が焼結鍛造体の表面からの距離
を示し、縦軸が表面欠陥の面積率を意味する。図８から
理解できるように、表面欠陥の面積率は圧粉体の密度に
大いに影響を受ける。即ち、圧粉体が低密度（ρ＝５．
８）であれば、焼結鍛造体の表面欠陥の面積率は高い。
表面の緻密化が低下しており、焼結体の表面酸化が進行
し易いためと推察される。しかし圧粉体が高密度（ρ＝
６．８）であれば、焼結鍛造体の表面欠陥の面積率は低
い。表面の緻密化が進んでおり、焼結体の表面酸化が進
行しにくいためと推察される。In FIG. 8, the horizontal axis represents the distance from the surface of the sintered forged body, and the vertical axis represents the area ratio of surface defects. As can be understood from FIG. 8, the area ratio of surface defects is greatly affected by the density of the green compact. That is, the green compact has a low density (ρ = 5.
If 8), the area ratio of surface defects of the sintered forged body is high.
It is presumed that the densification of the surface is low and the surface oxidation of the sintered body is likely to proceed. However, the green compact has a high density (ρ =
If it is 6.8), the area ratio of surface defects of the sintered forged body is low. It is speculated that the surface is becoming denser and the surface oxidation of the sintered body is less likely to proceed.
【００４７】従って圧粉体の密度を高めにできる効果が
得られる本発明方法によれば、焼結鍛造体の表面欠陥を
低減するのに有利である。故に焼結鍛造体の強度増加に
有利である。また図９は、圧粉体の密度と焼結鍛造体の
表面欠陥の面積率との関係を示す。図９の特性線から理
解できるように、圧粉体の密度が低くなれば、焼結鍛造
体の表面欠陥の面積率が増加し、圧粉体の密度が高くな
れば、焼結鍛造体の表面欠陥の面積率が低下することが
わかる。Therefore, according to the method of the present invention, which has the effect of increasing the density of the green compact, it is advantageous for reducing the surface defects of the sintered forged body. Therefore, it is advantageous for increasing the strength of the sintered forged body. Further, FIG. 9 shows the relationship between the density of the green compact and the area ratio of surface defects of the sintered forged body. As can be understood from the characteristic line of FIG. 9, when the density of the green compact is low, the area ratio of surface defects of the sintered forging body is increased, and when the density of the green compact is high, It can be seen that the area ratio of surface defects decreases.
【００４８】（付記）上記した実施例から次の技術的思
想も把握できる。 請求項１において、成形用粉末と成形型とは実質的に
等温領域であることを特徴とする粉末成形方法。 請求項１において、成形用粉末の温度＜成形型の温度
であることを特徴とする粉末成形方法。 請求項１において、成形用粉末の温度＞成形型の温度
であることを特徴とする粉末成形方法。 成形型から離れた待機位置と成形型に対面する位置と
の間で移動可能な粉箱を用い、待機中の粉箱内は減圧状
態または真空状態に維持可能とされていることを特徴と
する粉末成形方法。 成形キャビティを区画する型面を備えた粉末成形用の
成形型と、潤滑剤を実質的に含有しない成形用粉末とを
用い、成形型及び成形用粉末とを１５０〜４００°C の
温度領域に加熱すると共に、成形型の型面に潤滑剤を塗
布する工程と、成形型の成形キャビティに成形用粉末を
装填する工程と、成形キャビティに装填した成形用粉末
を圧縮成形して圧粉体とする工程と、圧粉体を焼結して
焼結体とする工程と、焼結体を鍛造して焼結鍛造体とす
る工程とを順に行うことを特徴とする焼結鍛造体の製造
方法。圧粉体の高密度化を図り得るため、焼結鍛造体の
表面欠陥を低減するのに有利であり、焼結鍛造体の強度
確保に貢献できる。(Supplementary Note) The following technical idea can be understood from the above-described embodiments. The powder molding method according to claim 1, wherein the molding powder and the molding die are substantially in the isothermal region. The powder molding method according to claim 1, wherein the temperature of the molding powder <the temperature of the molding die. The powder molding method according to claim 1, wherein the temperature of the molding powder> the temperature of the molding die. A powder box movable between a standby position separated from the mold and a position facing the mold is used, and the inside of the powder box on standby can be maintained in a reduced pressure state or a vacuum state. Powder molding method. Using a molding die for powder molding having a molding surface that defines a molding cavity and a molding powder that does not substantially contain a lubricant, the molding die and the molding powder are placed in a temperature range of 150 to 400 ° C. A step of applying a lubricant to the surface of the mold while heating, a step of loading the molding powder into the molding cavity of the molding die, and a step of compressing and molding the molding powder loaded in the molding cavity to obtain a green compact. And a step of sintering the green compact into a sintered body, and a step of forging the sintered body into a sintered forged body in this order. . Since the density of the green compact can be increased, it is advantageous in reducing the surface defects of the sintered forged body, and can contribute to ensuring the strength of the sintered forged body.
【００４９】[0049]
【発明の効果】本発明方法によれば、成形キャビティを
区画する型面を備えた粉末成形用の成形型と、潤滑剤を
実質的に含有しない成形用粉末とを用い、成形型及び成
形用粉末とを１５０〜４００°C の温度領域に加熱する
と共に、成形型の型面に潤滑剤を塗布する工程と、成形
型のキャビティに成形用粉末を装填する工程とを順に行
う。そのため圧粉体の密度、強度を高めるのに有利であ
る。EFFECTS OF THE INVENTION According to the method of the present invention, a molding die and a molding die for molding having a mold surface for defining a molding cavity and a molding powder substantially containing no lubricant are used. The powder and the powder are heated to a temperature range of 150 to 400 ° C., the step of applying a lubricant to the mold surface of the mold and the step of loading the mold powder into the cavity of the mold are sequentially performed. Therefore, it is advantageous to increase the density and strength of the green compact.
【００５０】このように圧粉体の密度を高くすれば、圧
粉体の表面のポアの低減に有利である。従って圧粉体を
焼結鍛造した場合に、焼結鍛造体の表面欠陥の低減に有
利であり、焼結鍛造体の強度の向上に一層有利である。Increasing the density of the green compact in this way is advantageous for reducing pores on the surface of the green compact. Therefore, when the green compact is sintered and forged, it is advantageous in reducing the surface defects of the sintered forged body, and is more advantageous in improving the strength of the sintered forged body.
【図１】実施例に係る構成図である。FIG. 1 is a configuration diagram according to an embodiment.
【図２】実施例に係る各工程を示す構成図である。FIG. 2 is a configuration diagram showing each process according to the embodiment.
【図３】他の実施例に係る構成図である。FIG. 3 is a configuration diagram according to another embodiment.
【図４】成形面圧を７〔ton/cm2 〕とした場合における
圧粉体密度を示すグラフである。FIG. 4 is a graph showing the compact density when the molding surface pressure is 7 [ton / cm 2 ].
【図５】成形体密度を７．１〔g/cm3 〕とした場合にお
ける圧粉体強度を示すグラフである。FIG. 5 is a graph showing the green compact strength when the compact density is 7.1 [g / cm 3 ].
【図６】成形面圧と圧粉体密度との関係を示すグラフで
ある。FIG. 6 is a graph showing the relationship between molding surface pressure and green compact density.
【図７】圧粉体密度と圧粉体強度との関係を示すグラフ
である。FIG. 7 is a graph showing the relationship between green compact density and green compact strength.
【図８】焼結鍛造体の表面からの距離と表面欠陥面積率
との関係を示すグラフである。FIG. 8 is a graph showing the relationship between the distance from the surface of the sintered forged body and the surface defect area ratio.
【図９】圧粉体密度と焼結鍛造体の表面欠陥面積率との
関係を示すグラフである。FIG. 9 is a graph showing the relationship between the green compact density and the surface defect area ratio of a sintered forged body.
図中、１は成形型、１１はダイス型、１３は上パンチ
型、１７は成形キャビティ、１１ｃ、１２ｃ、１３ｃ、
７３はヒータ、２は粉箱、３はスプレーノズルを示す。In the figure, 1 is a mold, 11 is a die mold, 13 is an upper punch mold, 17 is a molding cavity, 11c, 12c, 13c,
73 is a heater, 2 is a powder box, and 3 is a spray nozzle.
Claims (1)
末成形用の成形型と、潤滑剤を実質的に含有しない成形
用粉末とを用い、 前記成形型及び前記成形用粉末を１５０〜４００°C の
温度領域に加熱する加熱操作を行うと共に、前記成形型
の型面に前記潤滑剤を塗布する塗布操作とを行う工程
と、 前記温度領域に加熱された前記成形型の成形キャビティ
に、前記温度領域に加熱された前記成形用粉末を装填す
る工程と、 前記成形キャビティに装填した前記成形用粉末を圧縮成
形して圧粉体とする工程とを順に行うことを特徴とする
粉末成形方法。1. A molding die for powder molding having a mold surface for defining a molding cavity, and a molding powder containing substantially no lubricant, wherein the molding die and the molding powder are 150 to 400. Performing a heating operation of heating to a temperature range of ° C, and performing a coating operation of applying the lubricant to the mold surface of the mold, and a molding cavity of the mold heated to the temperature range, A powder molding method comprising sequentially performing a step of loading the heated molding powder in the temperature region and a step of compressing and molding the molding powder loaded in the molding cavity into a green compact. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8514696A JPH09272901A (en) | 1996-04-08 | 1996-04-08 | Powder molding method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8514696A JPH09272901A (en) | 1996-04-08 | 1996-04-08 | Powder molding method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09272901A true JPH09272901A (en) | 1997-10-21 |
Family
ID=13850531
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8514696A Pending JPH09272901A (en) | 1996-04-08 | 1996-04-08 | Powder molding method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09272901A (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001295915A (en) * | 2000-04-11 | 2001-10-26 | Hitachi Powdered Metals Co Ltd | Sintered sprocket for silent chain and method of manufacturing the same |
| US6344169B2 (en) | 1998-11-05 | 2002-02-05 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Method for compaction of powders for powder metallurgy |
| US6544352B2 (en) | 2000-02-09 | 2003-04-08 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Method for the compaction of soft magnetic powder |
| WO2004045841A1 (en) | 2002-11-21 | 2004-06-03 | Mitsubishi Materials Corporation | Method for forming compact from powder and mold apparatus for powder forming |
| US6749767B2 (en) | 2001-03-21 | 2004-06-15 | Kobe Steel Ltd | Powder for high strength dust core, high strength dust core and method for making same |
| WO2004087407A1 (en) * | 2003-03-28 | 2004-10-14 | Mitsubishi Materials Corporation | Powder molding die apparatus and method of molding for obtaining powder molding product |
| EP1724037A1 (en) * | 2004-02-27 | 2006-11-22 | Mitsubishi Materials PMG Corporation | Method of forming powder compact and mold assembly for powder compaction |
| US7459032B2 (en) * | 2001-06-13 | 2008-12-02 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Pressurizing forming process and pressurized-and-formed member |
| US8153053B2 (en) | 2002-11-21 | 2012-04-10 | Diamet Corporation | Method for forming compact from powder and sintered product |
| JP2013089688A (en) * | 2011-10-14 | 2013-05-13 | Sumitomo Electric Ind Ltd | Powder compact shaping method |
| JP2015213148A (en) * | 2013-11-29 | 2015-11-26 | 株式会社神戸製鋼所 | Mixed powder for powder magnetic core, and powder magnetic core |
| US10960633B2 (en) | 2015-03-20 | 2021-03-30 | Hitachi Chemical Company, Ltd. | Method for forming molded article by press molding |
-
1996
- 1996-04-08 JP JP8514696A patent/JPH09272901A/en active Pending
Cited By (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6344169B2 (en) | 1998-11-05 | 2002-02-05 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Method for compaction of powders for powder metallurgy |
| US6544352B2 (en) | 2000-02-09 | 2003-04-08 | Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) | Method for the compaction of soft magnetic powder |
| JP2001295915A (en) * | 2000-04-11 | 2001-10-26 | Hitachi Powdered Metals Co Ltd | Sintered sprocket for silent chain and method of manufacturing the same |
| US6749767B2 (en) | 2001-03-21 | 2004-06-15 | Kobe Steel Ltd | Powder for high strength dust core, high strength dust core and method for making same |
| US7459032B2 (en) * | 2001-06-13 | 2008-12-02 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Pressurizing forming process and pressurized-and-formed member |
| WO2004045841A1 (en) | 2002-11-21 | 2004-06-03 | Mitsubishi Materials Corporation | Method for forming compact from powder and mold apparatus for powder forming |
| EP1563986A1 (en) * | 2002-11-21 | 2005-08-17 | Mitsubishi Materials Corporation | Method for forming compact from powder and mold apparatus for powder forming |
| KR100706006B1 (en) * | 2002-11-21 | 2007-04-12 | 미쓰비시 마테리알 피엠지 가부시키가이샤 | Method for forming compact from powder and mold apparatus for powder forming |
| EP1563986A4 (en) * | 2002-11-21 | 2010-03-10 | Method for forming compact from powder and mold apparatus for powder forming | |
| US8153053B2 (en) | 2002-11-21 | 2012-04-10 | Diamet Corporation | Method for forming compact from powder and sintered product |
| EP2650116A3 (en) * | 2003-03-28 | 2013-10-30 | Diamet Corporation | Powder molding die apparatus and method of molding for obtaining powder molding product |
| WO2004087407A1 (en) * | 2003-03-28 | 2004-10-14 | Mitsubishi Materials Corporation | Powder molding die apparatus and method of molding for obtaining powder molding product |
| EP2650116A2 (en) * | 2003-03-28 | 2013-10-16 | Diamet Corporation | Powder molding die apparatus and method of molding for obtaining powder molding product |
| US7585165B2 (en) | 2003-03-28 | 2009-09-08 | Mitsubishi Materials Pmg Corporation | Powder molding die apparatus and method of molding for obtaining powder molding product |
| EP1724037A4 (en) * | 2004-02-27 | 2009-07-22 | Mitsubishi Materials Pmg Corp | Method of forming powder compact and mold assembly for powder compaction |
| KR101147590B1 (en) * | 2004-02-27 | 2012-05-21 | 가부시키가이샤 다이야멧트 | Method of forming powder compact and mold assembly for powder compaction |
| EP1724037A1 (en) * | 2004-02-27 | 2006-11-22 | Mitsubishi Materials PMG Corporation | Method of forming powder compact and mold assembly for powder compaction |
| JP2013089688A (en) * | 2011-10-14 | 2013-05-13 | Sumitomo Electric Ind Ltd | Powder compact shaping method |
| KR20140089377A (en) | 2011-10-14 | 2014-07-14 | 스미토모덴키고교가부시키가이샤 | Molding method for molded powder compact |
| US9431171B2 (en) | 2011-10-14 | 2016-08-30 | Sumitomo Electric Industries, Ltd. | Method for molding powder mold product |
| JP2015213148A (en) * | 2013-11-29 | 2015-11-26 | 株式会社神戸製鋼所 | Mixed powder for powder magnetic core, and powder magnetic core |
| US10960633B2 (en) | 2015-03-20 | 2021-03-30 | Hitachi Chemical Company, Ltd. | Method for forming molded article by press molding |
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