JPH07247173A - Die for isotropic pressure sintering - Google Patents
Die for isotropic pressure sinteringInfo
- Publication number
- JPH07247173A JPH07247173A JP6038592A JP3859294A JPH07247173A JP H07247173 A JPH07247173 A JP H07247173A JP 6038592 A JP6038592 A JP 6038592A JP 3859294 A JP3859294 A JP 3859294A JP H07247173 A JPH07247173 A JP H07247173A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- punch
- particles
- die
- sintering
- 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.)
- Withdrawn
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は加圧焼結用ダイス、特に
流動性の球状粒子を圧力伝達媒体とした加圧焼結に用い
る等方加圧焼結用ダイスに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure sintering die, and more particularly to an isotropic pressure sintering die which is used for pressure sintering using fluid spherical particles as a pressure transmitting medium.
【０００２】[0002]
【従来の技術】セラミックスや粉末金属の焼結方法とし
ては、無加圧の大気あるいは特殊雰囲気中で加熱する常
圧焼結法が一般的である。しかし一般に常圧焼結で得ら
れる諸特性は低く、特に難焼結性の材料の場合、常圧で
は十分な緻密化が達成されない。そこで、加熱と同時に
加圧し焼結を促進する方法が採られてきた。例えば、グ
ラファイト等でできたシリンダーに原料粉を直接充填
し、一軸方向に圧力を加えながら焼結するホットプレス
法では、常圧焼結で得られるよりはるかに優れた特性を
得ることができるが、単純形状のものしか焼結すること
ができないと言う問題がある。一方、複雑形状を有する
粉体成形体に等方圧を加えて焼結する熱間静水圧プレス
法（ＨＩＰ）があるが、圧力伝達に高温高圧ガスを用い
るため、圧力容器等の装置が大がかりで、高価という問
題がある。2. Description of the Related Art As a sintering method of ceramics and powder metal, an atmospheric pressure sintering method of heating in a non-pressurized atmosphere or a special atmosphere is generally used. However, the various properties obtained by normal pressure sintering are generally low, and particularly in the case of a material that is difficult to sinter, sufficient densification cannot be achieved at normal pressure. Therefore, a method has been adopted in which pressure is applied simultaneously with heating to promote sintering. For example, in a hot press method in which a raw material powder is directly filled in a cylinder made of graphite or the like and sintered while applying pressure in a uniaxial direction, it is possible to obtain far superior characteristics than those obtained by normal pressure sintering. However, there is a problem that only simple shapes can be sintered. On the other hand, there is a hot isostatic pressing (HIP) method in which a powder compact having a complicated shape is subjected to isotropic pressure for sintering, but since a high-temperature high-pressure gas is used for pressure transmission, a device such as a pressure vessel is large. And there is the problem of being expensive.
【０００３】ＨＩＰに代わる複雑形状品の等方加圧焼結
法として、米国特許第４，０４１，１２３号明細書がグ
ラファイトやＢＮなどの固形粉体を圧力伝達媒体として
用いた方法を提案した。この方法では従来のホットプレ
ス装置を用いて、ある程度複雑形状のものを焼結するこ
とができるが、固体粉末が予備加圧の段階で半硬化し、
また焼結温度においては圧力伝達媒体がさらに硬化して
しまうため、完全な等方加圧は実現できず、焼成収縮率
に異方性が生じてしまうという問題がある。また、米国
特許第４，５３９，１７５号明細書は成形体を一旦焼結
し、強度を上げた後再加熱して、流動性のある粒子中に
埋設し、加圧して緻密質焼成体を得る方法を考案した。
しかし、この方法は、一次的な焼結と加圧焼結が別に行
われ煩雑で、また、完全な等方圧力を得ることも困難で
ある。米国特許第４，９３３，１４０号明細書は米国特
許第４，５３９，１７５号明細書の方法を改良し、流動
性粒子（及び成形体）を通電にて加熱することによって
成形体及び流動性粒子の加熱及びその後のハンドリング
を簡単にすることを考案したが、一次焼結から二次的な
加圧焼結を行うという基本的なプロセスは米国特許第
４，５３９，１７５号明細書の方法と同様で、また、圧
力の異方性も同様に存在する。米国特許第５，２４６，
６３８号明細書は複雑な形状を有した被焼成体を導電
性、流動性を有する粒子中に埋設し、加圧しながら通電
加熱し焼結する方法を考案した。この方法によって米国
特許第４，５３９，１７５号明細書や米国特許第４，９
３３，１４０号明細書の方法のように焼結を２段階に分
けるという複雑さはなくなったが、等方圧の実現に関し
ては困難で、やはり加圧方向による異方性が生じる。As an isotropic pressure sintering method for a complex-shaped product instead of HIP, US Pat. No. 4,041,123 proposed a method using solid powder such as graphite or BN as a pressure transmission medium. . In this method, it is possible to sinter a complicated shape to some extent using a conventional hot press machine, but the solid powder is semi-cured at the stage of prepressing,
Further, since the pressure transmission medium is further hardened at the sintering temperature, perfect isotropic pressurization cannot be realized, and there is a problem that the firing shrinkage rate becomes anisotropic. Further, US Pat. No. 4,539,175 discloses that a molded body is once sintered, strengthened and then reheated, embedded in fluid particles, and pressed to obtain a dense fired body. Devised a way to get.
However, this method is complicated because primary sintering and pressure sintering are performed separately, and it is also difficult to obtain perfect isotropic pressure. U.S. Pat. No. 4,933,140 is a modification of the process of U.S. Pat. No. 4,539,175, in which the flowable particles (and the compact) are heated by energization to form a compact and flowability Although it was devised to simplify the heating and subsequent handling of the particles, the basic process from primary sintering to secondary pressure sintering is the method of US Pat. No. 4,539,175. Similarly, pressure anisotropy also exists. US Patent No. 5,246,
No. 638 has devised a method in which an object to be fired having a complicated shape is embedded in particles having electrical conductivity and fluidity, and current is heated while applying pressure to sinter. By this method, US Pat. No. 4,539,175 and US Pat.
Although the complexity of dividing the sintering into two stages as in the method of No. 33,140 is eliminated, it is difficult to realize isotropic pressure, and anisotropy depending on the pressing direction also occurs.
【０００４】さらに、粉体や粒子を圧力伝達物質として
等方加圧を実現するために、特開昭６３−１８０３９９
号公報及び特開昭６３−１８３７９８号公報は直交する
３軸方向から加圧する方法を提案したが、この方法だと
加圧装置が複雑となり、実用上の問題が生じる。Further, in order to realize isotropic pressurization by using powder or particles as a pressure transmitting substance, Japanese Patent Application Laid-Open No. 63-180399.
Japanese Patent Laid-Open No. 63-183798 and Japanese Patent Laid-Open No. 63-183798 have proposed a method of pressurizing from three orthogonal directions, but this method complicates the pressurizing device and causes practical problems.
【０００５】[0005]
【発明が解決しようとする課題】以上述べたように、等
方加圧焼結はＨＩＰ法の場合、高温高圧ガスを使用する
ために設備が大がかりで高価という問題もあり、またＨ
ＩＰ法以外の粉体や粒子を圧力伝達媒体として用いた方
法では等方加圧が不可能であったり、二段階の焼結を行
わなければならない等の問題があった。As described above, in the case of the HIP method, isotropic pressure sintering has a problem that the equipment is large and expensive because a high temperature and high pressure gas is used.
Methods other than the IP method using powder or particles as a pressure transmission medium have problems such as isotropic pressurization being impossible and two-step sintering being required.
【０００６】本発明は、上記の従来方法の問題点を解決
し、流動性の球状粒子を圧力伝達媒体とした加圧焼結に
おいて、等方加圧を実現するためのダイスを提供しよう
とするものである。The present invention solves the above-mentioned problems of the conventional method and provides a die for realizing isotropic pressing in pressure sintering using fluid spherical particles as a pressure transmitting medium. It is a thing.
【０００７】[0007]
【課題を解決するための手段】本発明の第一の発明は、
加圧焼結を行うためのダイスであって、一個または一対
の、加圧先端が加圧軸となす角度が１５度より大きく７
５度より小さい一つ以上の斜面によって構成されるパン
チと、そのパンチが貫通する開放孔を有するシリンダ
ー、及びシリンダーとパンチによって形成される加圧室
に充填された流動性の球状圧力伝達粒子によって構成さ
れ、パンチに一軸方向の荷重を加えることにより、粒子
中に埋設された成形体に等法的な圧力を加えることを特
徴とする一軸加圧焼結用ダイスである。The first invention of the present invention is as follows:
A die for performing pressure sintering, wherein the angle formed by one or a pair of pressure tips with the pressure axis is greater than 15 degrees.
A punch having one or more slopes smaller than 5 degrees, a cylinder having an open hole through which the punch penetrates, and a fluid spherical pressure-transmitting particle filled in a pressure chamber formed by the cylinder and the punch. A die for uniaxial pressure sintering, which is characterized in that a uniaxial pressure is applied to a punch to apply an isostatic pressure to a compact embedded in particles.
【０００８】図１に装置の概要を示す。図中の１で示さ
れる一軸方向の加圧力は２及び７の上下パンチによって
４の加圧室壁面に伝えられ、６の流動性の球状圧力伝達
粒子を介して５の成形体に伝えられる。図２に示すよう
に、加圧室壁面１０が加圧方向に対して斜角１１を有し
ていることから、一軸方向に加えられた加圧力８は圧力
伝達媒体である粒子９を経て加圧軸方向とは垂直方向に
も加圧力を生じ、成形体にはほぼ等方的な圧力が加わる
ことになる。ここで、等方的とは成形体の加圧軸と平行
な面に加わる圧力が、垂直な面に加わる圧力の８０％以
上であることを言う。緻密化を促進させるのに有効な圧
力は１．５MPa 以上で、成形体を破壊しない範囲で高い
方が緻密化により有効である。加圧力の上限は加圧室の
強度、加圧装置の能力によって決定される。FIG. 1 shows an outline of the apparatus. The pressing force in the uniaxial direction indicated by 1 in the figure is transmitted to the wall surface of the pressure chamber 4 by the upper and lower punches 2 and 7, and is transmitted to the molded body 5 via the fluid spherical pressure transmitting particles 6. As shown in FIG. 2, since the pressurizing chamber wall surface 10 has an oblique angle 11 with respect to the pressurizing direction, the pressurizing force 8 applied in the uniaxial direction is applied via the particles 9 as the pressure transmitting medium. A pressure is also generated in a direction perpendicular to the pressure axis direction, and a substantially isotropic pressure is applied to the molded body. Here, isotropic means that the pressure applied to the surface parallel to the pressing axis of the molded body is 80% or more of the pressure applied to the vertical surface. The effective pressure for promoting the densification is 1.5 MPa or more, and the higher the pressure is within the range where the compact is not destroyed, the more effective the densification is. The upper limit of the applied pressure is determined by the strength of the pressurizing chamber and the capacity of the pressurizing device.
【０００９】ここで用いられる圧力伝達粒子は、少なく
とも成形体の焼結温度以上の融点を有し、成形体の焼結
温度で成形体と反応せず、またそれ自体が焼結や、硬化
することなく、加圧力に対して十分な強度を有するもの
でなければならない。グラファイトや窒化ホウ素はその
一例である。また、シリンダー及びパンチの材質は加熱
温度において液化、あるいは軟化したり、強度低下のな
いものを選択しなければならず、グラファイトが最も一
般的と考えられる。The pressure-transmitting particles used here have a melting point of at least the sintering temperature of the molded body, do not react with the molded body at the sintering temperature of the molded body, and sinter or harden themselves. It must have sufficient strength against the applied pressure. Graphite and boron nitride are examples. Further, the material of the cylinder and the punch must be selected so as not to be liquefied or softened at the heating temperature and to have no strength decrease, and graphite is considered to be the most common.
【００１０】成形体は焼結可能な粉体によるものであれ
ば特にその種類は限定しないが、セラミックス、または
金属が一般的である。これらの粉体を、金型を用いた一
軸加圧、ＣＩＰ等の加圧成形、あるいはスリップキャス
ト、射出成形等の方法によって成形する。加圧による破
壊や欠陥の発生を防ぐため成形体の密度は４５％以上が
望ましい。または、成形体を一旦仮焼して強度を高めた
仮焼体を用いてもよい。The molded body is not particularly limited as long as it is made of sinterable powder, but ceramics or metal is generally used. These powders are molded by a method such as uniaxial pressure using a mold, pressure molding such as CIP, slip casting, or injection molding. The density of the molded body is preferably 45% or more in order to prevent destruction and defects due to pressure. Alternatively, a calcined body obtained by temporarily calcining the molded body to increase its strength may be used.
【００１１】以上のような方法で製造した成形体、ある
いは仮焼体を、加圧室内に充填された圧力伝達粒子中に
埋設し加圧する。加熱は加圧室周囲に設けられた発熱体
による間接加熱、あるいは圧力伝達媒体に通電する直接
加熱いずれの方法でもよい。また、成形体強度が低く、
焼結前に加圧によって破壊される可能性がある場合は、
無加圧で仮焼し、成形体強度を高めた後圧力を加えても
よい。昇温速度、保持時間等の加熱パターンは成形体の
組成によってまちまちでありここでは特に特定しない。
緻密化完了後は冷却し、圧力伝達媒体から取り出すこと
によって緻密な焼結体を得ることができる。The molded body or the calcined body manufactured by the above method is embedded in the pressure transmitting particles filled in the pressure chamber and pressurized. The heating may be either indirect heating by a heating element provided around the pressurizing chamber or direct heating by energizing the pressure transmitting medium. Also, the strength of the molded body is low,
If it can be destroyed by pressure before sintering,
The pressure may be applied after calcining without pressure to increase the strength of the molded body. The heating pattern such as the temperature rising rate and the holding time varies depending on the composition of the molded body and is not particularly specified here.
After the densification is completed, it is cooled and taken out from the pressure transmission medium, whereby a dense sintered body can be obtained.
【００１２】本発明の第二の発明は、第一の発明に記載
されたダイスで、パンチの加圧先端の形状が半球凹面形
状のものである。パンチの加圧先端の形状が半球凹面と
した場合にも、本発明の第一の発明に記載したと同様の
作用によって、圧力伝達粒子中に埋設された成形体にほ
ぼ等方的な圧力が加えることができる。装置の制約上、
ダイスの高さに制限がある場合など、等方加圧の効果を
保持しながらダイスの高さを低く押さえる場合に有効で
ある。A second invention of the present invention is the die described in the first invention, wherein the pressing tip of the punch has a hemispherical concave shape. Even when the shape of the pressing tip of the punch is a hemispherical concave surface, a substantially isotropic pressure is exerted on the molded body embedded in the pressure transmitting particles by the same action as described in the first invention of the present invention. Can be added. Due to equipment limitations,
This is effective when the height of the die is kept low while maintaining the effect of isotropic pressing, such as when the height of the die is limited.
【００１３】本発明の第三の発明は、請求項の第１項及
び２項に記載されたダイスで、平坦な先端を有するパン
チに、加圧室を形成するための形状を有したスペーサー
を取り付け、ダイス作成の簡便性や、修繕性を高めたも
のである。図３にその概念図を示す。平坦な端面を有す
る上下パンチ１２及び１４の先端に、加圧室を形成でき
るようなスペーサー１３が取り付けられている。このよ
うな加圧室を形成する部分をパンチと別部品とすること
によって、本装置の製造も容易となり、また、通常最も
消耗する加圧室部分のみの取り替えも可能となり、修繕
性を改善することができる。パンチとスペーサーの合わ
せ面に山溝等の嵌合部を設けると、作業性がさらに改善
される。また、シリンダーの内面にスリーブを設ける
と、シリンダーの修繕性を向上させることができる。A third aspect of the present invention is the die described in the first and second aspects of the present invention, wherein a punch having a flat tip is provided with a spacer having a shape for forming a pressurizing chamber. It is easy to install and make dies, and has improved repairability. The conceptual diagram is shown in FIG. A spacer 13 capable of forming a pressurizing chamber is attached to the tips of the upper and lower punches 12 and 14 having flat end faces. By making the part forming such a pressurizing chamber as a separate part from the punch, the manufacturing of this device is facilitated, and it is possible to replace only the part of the pressurizing chamber that is normally consumed most, improving the repairability. be able to. Providing a fitting portion such as a mountain groove on the mating surface of the punch and the spacer further improves workability. Further, by providing the sleeve on the inner surface of the cylinder, the repairability of the cylinder can be improved.
【００１４】[0014]
（実施例１）２０重量％のグラファイトを含む炭化チタ
ンを、一軸加圧後ＣＩＰによって成形し理論密度の６５
％の成形体を得、４０×４０×４０mmの板状に加工して
被焼成体とした。次に、内径９０mmのホットプレス用グ
ラファイト製シリンダーに、斜面角度４５度の円錐凹面
状の端面形状を有する下パンチを挿入し、これに１５０
ｇの流動性球状黒鉛粒子（Superior Graphite Co. 製＃
９４００球状黒鉛粒子、米国、イリノイ州）を加え、平
らになるように表面を整えた。このようにして整えた粒
子床の軸中心に被焼成体を静かに置き、これに１８０ｇ
の流動性球状黒鉛粒子を加えて被焼成体を埋設した。こ
れに端面形状を下パンチと同様に加工した上パンチを装
着し、図１に示したような流動性球状黒鉛粒子中に被焼
成体を埋設した加圧室を形成した。このようにして準備
した加圧室をホットプレス装置に組み込み、アルゴン雰
囲気中で、次の条件で加圧昇温を行った。まず、昇温開
始前に３MPa の圧力を加えた。次に２１００℃まで昇温
し、同温度同圧力で２時間保持した。その後冷却して、
緻密化した焼成体を得た。得られた焼結体の寸法、収縮
率、並びに相対密度を表１に示す。わずか３MPa の加圧
で９５．２％まで緻密化が進んでおり、また収縮率の異
方性も十分に小さいことがわかる。Example 1 Titanium carbide containing 20% by weight of graphite was uniaxially pressed and then molded by CIP to have a theoretical density of 65.
%, And processed into a plate of 40 × 40 × 40 mm to obtain a body to be fired. Next, a lower punch having a conical concave end face shape with a slope angle of 45 degrees was inserted into a graphite cylinder for hot pressing with an inner diameter of 90 mm, and 150
g of fluid spherical graphite particles (Superior Graphite Co.
9400 spheroidal graphite particles, Illinois, USA) were added and the surface was laid flat. The object to be fired is gently placed on the axis center of the particle bed thus prepared, and 180 g
The fluidized spherical graphite particles were added to embed the article to be fired. An upper punch whose end surface shape was processed in the same manner as the lower punch was attached to this, and a pressurizing chamber was formed in which the object to be fired was embedded in the fluid spherical graphite particles as shown in FIG. The pressurizing chamber thus prepared was incorporated into a hot press machine, and pressurizing and heating were performed under the following conditions in an argon atmosphere. First, a pressure of 3 MPa was applied before starting the temperature rise. Next, the temperature was raised to 2100 ° C., and the temperature and pressure were maintained for 2 hours. Then cool down,
A densified fired body was obtained. Table 1 shows the dimensions, shrinkage ratio, and relative density of the obtained sintered body. It can be seen that the densification progressed to 95.2% with a pressurization of only 3 MPa, and the anisotropy of the shrinkage ratio was sufficiently small.
【００１５】（実施例２）実施例１と同様の被焼成体を
同様の容器と方法を用いて流動性球状黒鉛粒子中に埋設
して、ホットプレス装置に組み込んだ。温度・圧力条件
は次の通りである。まず、昇温開始前に３MPa の圧力を
加えた。次に２１００℃まで昇温し、同温度同圧力で１
時間保持した後、圧力を２０MPa まで上昇させてさらに
１時間同温度で保持した。その後冷却して、緻密化した
焼成体を得た。得られた焼成体の寸法、収縮率、並びに
相対密度を表１に示す。２０MPa の加圧での加圧により
緻密化はさらに進み、相対密度は９８．１％まで上昇し
た。加圧軸方向の収縮率が他方向のそれに比べて若干大
きいものの、おおむね等方的な収縮といえる。(Example 2) The same object to be fired as in Example 1 was embedded in fluid spherical graphite particles using the same container and method, and incorporated in a hot press machine. The temperature and pressure conditions are as follows. First, a pressure of 3 MPa was applied before starting the temperature rise. Next, the temperature is raised to 2100 ° C. and the temperature and pressure are adjusted to 1
After holding for a period of time, the pressure was raised to 20 MPa and the temperature was kept for another hour. Then, the mixture was cooled to obtain a densified fired body. Table 1 shows the dimensions, shrinkage ratio, and relative density of the obtained fired body. The densification further progressed by pressurization at 20 MPa, and the relative density increased to 98.1%. Although the shrinkage ratio in the direction of the pressing axis is slightly larger than that in the other direction, it can be said to be roughly isotropic shrinkage.
【００１６】（実施例３）焼結助剤としてイットリアを
４重量％含む窒化珪素を、実施例１と同様の方法で成形
し５５％の成形体を得、実施例１と同形状の被焼成体に
加工した。この被焼成体を実施例１と同様の要領で流動
性球状黒鉛粒子中に埋設して、ホットプレス装置に組み
込んだ。温度・圧力条件は次の通りである。まず、昇温
開始前に３MPa の圧力を加えた。次に１７５０℃まで昇
温し、同温度同圧力で３０分保持した後、圧力を２０MP
a まで上昇させてさらに３０分同温度で保持した。その
後冷却して、緻密化した焼成体を得た。得られた焼成体
の寸法、収縮率、並びに相対密度を表１に示す。得られ
た焼成体の相対密度は９８．７％で、収縮率の異方性も
小さい。(Example 3) Silicon nitride containing 4% by weight of yttria as a sintering aid was molded in the same manner as in Example 1 to obtain a 55% compact, which was fired in the same shape as in Example 1. Processed into a body. This body to be fired was embedded in fluid spherical graphite particles in the same manner as in Example 1 and incorporated in a hot press machine. The temperature and pressure conditions are as follows. First, a pressure of 3 MPa was applied before starting the temperature rise. Next, after raising the temperature to 1750 ° C. and maintaining the same temperature and pressure for 30 minutes, the pressure is set to 20MP.
The temperature was raised to a and held at the same temperature for 30 minutes. Then, the mixture was cooled to obtain a densified fired body. Table 1 shows the dimensions, shrinkage ratio, and relative density of the obtained fired body. The relative density of the obtained fired body was 98.7%, and the anisotropy of shrinkage was small.
【００１７】（実施例４）加圧室の形状の加圧力の異方
性に与える影響を明らかにするため、次の要領で加圧室
内圧力分布の測定を行った。測定に用いた容器は内径９
０mmの貫通孔を持つグラファイト製で、この貫通孔に
（１）合わせ面が加圧軸に対して垂直をなす平面である
上下パンチが挿入され、円柱状の加圧室を形成するも
の、（２）上下のパンチとも合わせ面が斜面角度４５度
の円錐凹面状の端面形状を有し、２つの円錐を底面で接
合したような形状の加圧室を形成するもの、及び（３）
上下のパンチとも合わせ面が半球凹面状の端面形状を有
し、球形の加圧室を形成するものを用いた。図４の
（１）〜（３）に比較を行った加圧室の概要と、圧力の
測定位置を示す。それぞれの加圧室には、実施例１〜３
で使用したものと同じ流動性球状黒鉛粒子（Superior G
raphite Co. 製＃９４００球状黒鉛粒子、米国、イリノ
イ州）が、それぞれ９６０ｇ、３８３ｇ、６７０ｇが充
填されており、図４中に示す位置には感圧紙を、加圧軸
に対して垂直及び平行方向に埋設し、上下のパンチ間に
６５００Kgの加重を加えた場合の両方向に加わる圧力を
測定し、表２に示した。Example 4 In order to clarify the influence of the shape of the pressurizing chamber on the anisotropy of the pressing force, the pressure distribution in the pressurizing chamber was measured in the following manner. The inner diameter of the container used for measurement is 9
Made of graphite with 0 mm through-holes, and (1) upper and lower punches whose (1) mating surface is a plane perpendicular to the pressure axis are inserted into the through-holes to form a cylindrical pressure chamber, 2) The upper and lower punches each have a conical concave end surface shape with a mating surface having a slope angle of 45 degrees to form a pressurizing chamber having a shape in which two cones are joined at the bottom surface, and (3)
The upper and lower punches each had a mating surface having a hemispherical concave end surface shape and formed a spherical pressurizing chamber. The outline of the pressurizing chamber and the measurement position of pressure are shown in (1) to (3) of FIG. In each pressurizing chamber, Examples 1-3 are provided.
Same flowable spherical graphite particles (Superior G
# 9400 spherical graphite particles manufactured by raphite Co., Illinois, USA, filled with 960 g, 383 g, and 670 g, respectively. A pressure-sensitive paper was placed at the position shown in FIG. Table 2 shows the pressure applied in both directions in the case of embedding in the same direction and applying a load of 6500 kg between the upper and lower punches.
【００１８】この測定の結果、（１）の円柱状の加圧室
の場合、加圧軸と垂直面に加わる平均圧力は８．９MPa
で、水平面にかかる圧力はその６２％の５．５MPa にす
ぎず、加圧力に大きな異方性があることが確認された。
（２）の円錐凹面状の端面形状を有したパンチを用いた
場合、加圧軸と垂直面に加わる平均圧力は１０．１MPa
で、水平面にかかる圧力は９．３MPa と、垂直方向の９
２％に達している。（３）の半球凹面状の端面形状を有
したパンチを用いた場合、加圧軸と垂直面に加わる平均
圧力は８．９MPa で、水平面にかかる圧力は８．２MPa
と、（２）の場合と同様に垂直方向の９２％であった。
以上のように、本発明の形状を有した装置を用いること
によって、圧力伝達媒体中の加圧力の異方性を大幅に改
善することができた。As a result of this measurement, in the case of the columnar pressure chamber of (1), the average pressure applied to the surface perpendicular to the pressure axis is 8.9 MPa.
It was confirmed that the pressure applied to the horizontal surface was only 5.5 MPa, which was 62% of that, and the pressing force had a large anisotropy.
When the punch having the conical concave end face shape of (2) is used, the average pressure applied to the surface perpendicular to the pressing axis is 10.1 MPa.
The pressure on the horizontal surface is 9.3MPa, which is 9 in the vertical direction.
It has reached 2%. When the punch having the hemispherical concave end face shape of (3) is used, the average pressure applied to the vertical surface to the pressing axis is 8.9 MPa, and the pressure applied to the horizontal surface is 8.2 MPa.
As in the case of (2), it was 92% in the vertical direction.
As described above, by using the device having the shape of the present invention, the anisotropy of the pressing force in the pressure transmission medium could be significantly improved.
【００１９】（比較例１）実施例１と同様の被焼成体
を、大気圧のアルゴン雰囲気中、２１００℃で２時間焼
結した。得られた焼成体の寸法、収縮率、並びに相対密
度を表１に示す。このような常圧焼結では、収縮異方性
は小さいものの、相対密度は８６．０％までしか上がら
なかった。(Comparative Example 1) The same object to be fired as in Example 1 was sintered at 2100 ° C for 2 hours in an argon atmosphere at atmospheric pressure. Table 1 shows the dimensions, shrinkage ratio, and relative density of the obtained fired body. With such normal pressure sintering, the shrinkage anisotropy was small, but the relative density increased only to 86.0%.
【００２０】（比較例２）実施例３と同様の被焼成体
を、大気圧の窒素雰囲気中、１７５０℃で１時間焼結し
た。得られた焼成体の寸法、収縮率、並びに相対密度を
表１に示す。相対密度は９５．３％であった。Comparative Example 2 The same material to be fired as in Example 3 was sintered at 1750 ° C. for 1 hour in a nitrogen atmosphere at atmospheric pressure. Table 1 shows the dimensions, shrinkage ratio, and relative density of the obtained fired body. The relative density was 95.3%.
【００２１】（比較例３）実施例１と同様の被焼成体
を、加圧先端が平坦なダイスを用いて、実施例１と同様
の条件で加圧焼成した。得られた焼成体の寸法、収縮
率、並びに相対密度を表１に示す。得られた焼成体の相
対密度は実施例１のそれとほぼ同様であるが、加圧軸と
直交する方向（Ｘ，Ｙ）の収縮率と、平行する方向
（Ｚ）の収縮率に大きな異方性が生じることがわかる。(Comparative Example 3) A body to be fired similar to that in Example 1 was pressure-fired under the same conditions as in Example 1 using a die having a flat pressing tip. Table 1 shows the dimensions, shrinkage ratio, and relative density of the obtained fired body. The relative density of the obtained fired body was almost the same as that of Example 1, but a large anisotropy was found between the shrinkage rate in the directions (X, Y) orthogonal to the pressure axis and the shrinkage rate in the parallel direction (Z). It can be seen that sex occurs.
【００２２】（比較例４）実施例３と同様の被焼成体
を、加圧先端が平坦なダイスを用いて、実施例３と同様
の条件で加圧焼成した。得られた焼成体の寸法、収縮
率、並びに相対密度を表１に示す。得られた焼成体の相
対密度は実施例３のそれとほぼ同様であるが、加圧軸と
直交する方向（Ｘ，Ｙ）の収縮率と、平行する方向
（Ｚ）の収縮率に大きな異方性が生じることがわかる。(Comparative Example 4) A body to be fired similar to that in Example 3 was pressure-fired under the same conditions as in Example 3 using a die having a flat pressing tip. Table 1 shows the dimensions, shrinkage ratio, and relative density of the obtained fired body. The relative density of the obtained fired body was almost the same as that of Example 3, but the shrinkage rate in the directions (X, Y) orthogonal to the pressing axis and the shrinkage rate in the parallel direction (Z) were significantly anisotropic. It can be seen that sex occurs.
【００２３】[0023]
【表１】 [Table 1]
【００２４】[0024]
【表２】 [Table 2]
【００２５】[0025]
【発明の効果】本発明によって、圧力伝達粒子を用いた
セラミックスや金属等の良好な等方加圧焼成が実現でき
る。According to the present invention, good isotropic pressure firing of ceramics or metals using pressure transmitting particles can be realized.
【図１】等方加圧装置の概要である。FIG. 1 is an outline of an isotropic pressurizing device.
【図２】斜角を有するパンチの壁面に接した球状粒子に
働く加圧力を示す。FIG. 2 shows a pressing force applied to spherical particles in contact with a wall surface of a punch having an oblique angle.
【図３】パンチの先端にスペーサを取り付けて等方加圧
室を成形する装置の概要である。FIG. 3 is an outline of an apparatus for forming a isotropic pressure chamber by attaching a spacer to the tip of a punch.
【図４】加圧力異方性の比較に用いた加圧室の概要と、
圧力の測定位置を示す。FIG. 4 is an outline of a pressurizing chamber used for comparison of pressure anisotropy,
The pressure measurement position is shown.
１，８ 加圧力 ２，１２ 上パンチ ３ ダイス ４，１０ 加圧室・壁面 ５ 成形体 ６ 圧力伝達粒子 ７，１４ 下パンチ ９ 粒子 １１ 斜角 １３ スペーサ 1,8 Pressurization 2,12 Upper punch 3 Dies 4,10 Pressurizing chamber / wall surface 5 Molded body 6 Pressure transmission particles 7,14 Lower punch 9 Particles 11 Bevel 13 Spacer
───────────────────────────────────────────────────── フロントページの続き (72)発明者 佐藤 裕 神奈川県川崎市中原区井田1618番地 新日 本製鐵株式会社先端技術研究所内 (72)発明者 遠藤 英宏 神奈川県川崎市中原区井田1618番地 新日 本製鐵株式会社先端技術研究所内 (72)発明者 植木 正憲 神奈川県川崎市中原区井田1618番地 新日 本製鐵株式会社先端技術研究所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yutaka Sato 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Inside Advanced Technology Research Laboratories, Nippon Steel Corporation (72) Hidehiro Endo 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Address Nippon Steel Co., Ltd. Advanced Technology Research Laboratory (72) Inventor Masanori Ueki 1618 Ida, Nakahara-ku, Kawasaki City, Kanagawa Pref.
Claims (3)
一個または一対の、加圧先端が加圧軸となす角度が１５
度より大きく７５度より小さい一つ以上の斜面によって
構成されるパンチと、そのパンチが貫通する開放孔を有
するシリンダー、及びシリンダーとパンチによって形成
される加圧室に充填された流動性の球状圧力伝達粒子に
よって構成され、パンチに一軸方向の荷重を加えること
により、粒子中に埋設された成形体に等方的な圧力を加
えることを特徴とする一軸加圧焼結用ダイス。1. A die for performing pressure sintering, comprising:
The angle between one or a pair of pressure tips and the pressure axis is 15
A punch having one or more bevels greater than 75 degrees and less than 75 degrees, a cylinder having an open hole through which the punch penetrates, and a fluid spherical pressure filled in a pressurizing chamber formed by the cylinder and the punch. A die for uniaxial pressure sintering, which is composed of transfer particles and isotropically applied to a compact embedded in the particles by applying a uniaxial load to the punch.
なす請求項１記載のダイス。2. The die according to claim 1, wherein the pressing tip of the punch has a hemispherical concave shape.
形成するための形状を有したスペーサーを取り付けてな
る請求項１又は２記載のダイス。3. The die according to claim 1, wherein a punch having a flat tip is provided with a spacer having a shape for forming a pressure chamber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6038592A JPH07247173A (en) | 1994-03-09 | 1994-03-09 | Die for isotropic pressure sintering |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6038592A JPH07247173A (en) | 1994-03-09 | 1994-03-09 | Die for isotropic pressure sintering |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07247173A true JPH07247173A (en) | 1995-09-26 |
Family
ID=12529575
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6038592A Withdrawn JPH07247173A (en) | 1994-03-09 | 1994-03-09 | Die for isotropic pressure sintering |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07247173A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009513922A (en) * | 2005-10-27 | 2009-04-02 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Uniaxial pressurizing and heating device |
| CN110205984A (en) * | 2019-06-06 | 2019-09-06 | 嘉兴望族实业有限公司 | A kind of precast concrete ecology staged slope protection mold |
| JP2021027288A (en) * | 2019-08-08 | 2021-02-22 | 富士電機株式会社 | Semiconductor device and manufacturing method of the same |
-
1994
- 1994-03-09 JP JP6038592A patent/JPH07247173A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009513922A (en) * | 2005-10-27 | 2009-04-02 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Uniaxial pressurizing and heating device |
| CN110205984A (en) * | 2019-06-06 | 2019-09-06 | 嘉兴望族实业有限公司 | A kind of precast concrete ecology staged slope protection mold |
| JP2021027288A (en) * | 2019-08-08 | 2021-02-22 | 富士電機株式会社 | Semiconductor device and manufacturing method of the same |
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