JPS63307203A - Wet metallurgical method for producing finely divided or spherical metal powder - Google Patents
Wet metallurgical method for producing finely divided or spherical metal powderInfo
- Publication number
- JPS63307203A JPS63307203A JP63126049A JP12604988A JPS63307203A JP S63307203 A JPS63307203 A JP S63307203A JP 63126049 A JP63126049 A JP 63126049A JP 12604988 A JP12604988 A JP 12604988A JP S63307203 A JPS63307203 A JP S63307203A
- Authority
- JP
- Japan
- Prior art keywords
- metal
- particles
- powder
- droplets
- acid
- 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
- 239000000843 powder Substances 0.000 title claims description 43
- 229910052751 metal Inorganic materials 0.000 title claims description 37
- 239000002184 metal Substances 0.000 title claims description 37
- 238000004519 manufacturing process Methods 0.000 title description 5
- 239000002245 particle Substances 0.000 claims description 40
- 238000000034 method Methods 0.000 claims description 25
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 10
- 238000001816 cooling Methods 0.000 claims description 9
- 239000002253 acid Substances 0.000 claims description 7
- 238000001704 evaporation Methods 0.000 claims description 7
- 239000000203 mixture Substances 0.000 claims description 7
- 239000000243 solution Substances 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 230000008020 evaporation Effects 0.000 claims description 6
- 150000003839 salts Chemical class 0.000 claims description 6
- 239000012159 carrier gas Substances 0.000 claims description 5
- 239000011261 inert gas Substances 0.000 claims description 5
- 229910052500 inorganic mineral Inorganic materials 0.000 claims description 5
- 239000011707 mineral Substances 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 5
- 239000007864 aqueous solution Substances 0.000 claims description 4
- 239000002923 metal particle Substances 0.000 claims description 4
- 238000010951 particle size reduction Methods 0.000 claims description 4
- 150000004679 hydroxides Chemical class 0.000 claims description 3
- 150000004706 metal oxides Chemical class 0.000 claims description 3
- 239000011343 solid material Substances 0.000 claims description 3
- 239000008346 aqueous phase Substances 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims 1
- 229910017604 nitric acid Inorganic materials 0.000 claims 1
- 239000007789 gas Substances 0.000 description 17
- 238000002844 melting Methods 0.000 description 16
- 230000008018 melting Effects 0.000 description 16
- 239000012809 cooling fluid Substances 0.000 description 12
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 6
- 229910045601 alloy Inorganic materials 0.000 description 6
- 239000000956 alloy Substances 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 5
- 150000002736 metal compounds Chemical class 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- 239000012798 spherical particle Substances 0.000 description 4
- 239000007921 spray Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 3
- 150000007513 acids Chemical class 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 235000010755 mineral Nutrition 0.000 description 3
- 229910052750 molybdenum Inorganic materials 0.000 description 3
- 239000011733 molybdenum Substances 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 239000003380 propellant Substances 0.000 description 3
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 2
- 229910001111 Fine metal Inorganic materials 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000000227 grinding Methods 0.000 description 2
- 230000036571 hydration Effects 0.000 description 2
- 238000006703 hydration reaction Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 238000003801 milling Methods 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 230000002940 repellent Effects 0.000 description 2
- 239000005871 repellent Substances 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 238000007751 thermal spraying Methods 0.000 description 2
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 229910003296 Ni-Mo Inorganic materials 0.000 description 1
- 208000034809 Product contamination Diseases 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 235000019270 ammonium chloride Nutrition 0.000 description 1
- 239000000908 ammonium hydroxide Substances 0.000 description 1
- APUPEJJSWDHEBO-UHFFFAOYSA-P ammonium molybdate Chemical compound [NH4+].[NH4+].[O-][Mo]([O-])(=O)=O APUPEJJSWDHEBO-UHFFFAOYSA-P 0.000 description 1
- 239000011609 ammonium molybdate Substances 0.000 description 1
- 229940010552 ammonium molybdate Drugs 0.000 description 1
- 235000018660 ammonium molybdate Nutrition 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 239000011260 aqueous acid Substances 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000001112 coagulating effect Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000004035 construction material Substances 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010891 electric arc Methods 0.000 description 1
- QFXZANXYUCUTQH-UHFFFAOYSA-N ethynol Chemical group OC#C QFXZANXYUCUTQH-UHFFFAOYSA-N 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000002737 fuel gas Substances 0.000 description 1
- 239000003517 fume Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 229910000765 intermetallic Inorganic materials 0.000 description 1
- 239000011872 intimate mixture Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 229910000000 metal hydroxide Inorganic materials 0.000 description 1
- 150000004692 metal hydroxides Chemical class 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- -1 oxides Chemical class 0.000 description 1
- 238000007750 plasma spraying Methods 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000007712 rapid solidification Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000005549 size reduction Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/06—Metallic powder characterised by the shape of the particles
- B22F1/065—Spherical particles
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
本発明は、金属粉末の調製方法に関するものであり、特
には実質上球状粒子を有するそうした粉末の製造方法に
関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for preparing metal powders, and in particular to a method for producing such powders having substantially spherical particles.
厘米肢巷
米国特許第３，６６３，６６７号は多金属合金粉末を製
造するための方法を開示する。即ち、ここでは、多金属
合金粉末は、少なくとも２種の、熱的に還元しつる金属
化合物と水の水溶液を形成し、溶液を加熱された気体を
含む室内で約１５０ミクロン以下の寸法を有する液滴に
噴霧し、それにより個々の固体粒子を形成し、そして後
粒子を還元性雰囲気においてそして金属化合物を還元す
るに十分の且つ合金を構成する金属のいずれの融点より
も低い温度において加熱する方法により製造される。US Pat. No. 3,663,667 to Limai Liang discloses a method for producing polymetallic alloy powders. That is, herein, the polymetallic alloy powder is formed into an aqueous solution of at least two thermally reduced metal compounds and water, and the solution is placed in a chamber containing a heated gas having dimensions of about 150 microns or less. atomizing droplets, thereby forming individual solid particles, and heating the subsequent particles in a reducing atmosphere and at a temperature sufficient to reduce the metal compound and below the melting point of any of the metals making up the alloy. manufactured by the method.
米国特許第３，９０９，２４１号は、凝集塊を高温プラ
ズマ反応器を通して給送して粒子の少なくとも部分溶融
をもたらし、そして保護性の気体雰囲気を有する冷却室
において粒子を収集し、ここで粒子を凝固せしめること
により製造される自由流動性の粉末に関係する。この特
許において、粉末は、プラズマコーティングのため使用
されそして凝集原料は金属粉末及び結合剤のスラリーか
ら生成される。U.S. Pat. No. 3,909,241 pumps the agglomerate through a high temperature plasma reactor to effect at least partial melting of the particles, and collects the particles in a cooling chamber with a protective gas atmosphere, where the particles pertains to free-flowing powders produced by coagulating In this patent, powder is used for plasma coating and agglomerated feedstock is produced from a slurry of metal powder and binder.
１９８４年８月２日公開された欧州特許ＷＯ３４０２８
６４号において、溶融液滴の流れをはじき易い反撥性表
面に差し向け、それにより液滴な分断しそしてはねかし
めそして後凝固せしめることによる超微粉末の製造方法
が開示される。はね返り後に球状粒子が形成される傾向
があるが、溶融部分は楕円状或いは丸みの付いた端を有
する細長い粒子を形成し易いと記載されている。European patent WO34028 published on August 2, 1984
No. 64 discloses a method for producing ultrafine powders by directing a stream of molten droplets onto a repellent, repellent surface, thereby causing the droplets to break up and splatter and subsequently solidify. Although spherical particles tend to form after rebound, it is stated that the fused portion tends to form elongated particles with ellipsoidal or rounded edges.
明が ゛しようとする５題
上記方法は、生成材料の相対的に多、くの部分が約２０
μｍを越える、非球状の金属粉末しか生成し得なかった
。The five methods proposed by Akira are based on a relatively large proportion of the produced material, with a large proportion of about 20
Only non-spherical metal powder exceeding μm could be produced.
近時１、粉末冶金、エルクトロニクス等の分野において
、約２０μより小さな寸法の球状の微細金属粉末を得る
ことへの要望が存在する。Recently, there has been a desire in the fields of powder metallurgy, elctronics, etc. to obtain spherical fine metal powders with dimensions smaller than about 20 microns.
こうした目的に対しては、特殊な方法によらずに、細分
された金属乃至金属合金粉末を個々の金属源から湿式冶
金法により製造しそして熱的に球状化することを可能な
らしめる比較的簡単な方法の開発は斯界に大きな貢献を
なすものと信ぜられる。For these purposes, relatively simple methods are used which allow finely divided metal or metal alloy powders to be produced hydrometallurgically from individual metal sources and thermally spheronized without special methods. It is believed that the development of such a method will make a major contribution to this field.
犬旦ｍ果
本発明に従えば、微細な金属球状粉末を製造する方法が
提供される。この方法は、少なくとも１種の金属分を含
有する水溶液を形成しそして後金属塩、金属酸化物等並
びにその混合物から成る群から選択される還元性金属材
料を形成するに十分の水を蒸発せしめそして材料を還元
して金属粒子を形成することから出発する。金属粉末粒
子の少なくとも一部はキャリヤガスに連行せしめられ、
そして高温帯域に送給される。粒子の少なくとも一部は
少なくとも部分的に溶融せしめられそして凝固に際して
約２０μｍ未満の平均粒寸を有する球状粒子を形成する
。粒寸の減縮な、還元性金属材料にあるいは金属粒子に
爾後の処理に先立って実施することが出来る。According to the present invention, a method for producing fine metal spherical powder is provided. The method comprises forming an aqueous solution containing at least one metal component and then evaporating sufficient water to form a reducible metal material selected from the group consisting of metal salts, metal oxides, etc., and mixtures thereof. The process then begins by reducing the material to form metal particles. at least a portion of the metal powder particles are entrained in a carrier gas;
It is then fed to the high temperature zone. At least a portion of the particles are at least partially fused and upon solidification form spherical particles having an average particle size of less than about 20 μm. Particle size reduction can be carried out on reducible metal materials or on metal particles prior to further processing.
Ｋ嵐皿辺且」
本発明の実施における出発物質として金属粉末の使用が
、そうした粉末材料は他の形態の金属より一層容易に溶
解するので好ましいが、粉末の使用は必須ではない。水
に或いは水性鉱酸に可溶の金属塩が使用されつる。合金
が所望されるとき、続いて形成される塩、酸化物或いは
水酸化物固体中の様々の金属の金属比率が出発原料に基
づいて計算しうるし或いは合金が製造されている場合に
該固体をサンプリングしそして金属比率を分析してもよ
い。金属分は任意の水溶性酸に溶解されうる。酸として
は、鉱酸並びに酢酸、ギ酸等の有機酸が挙げられる。塩
酸がそのコスト及び入手性により特に好ましい。Although the use of metal powders as starting materials in the practice of the present invention is preferred as such powder materials are more easily dissolved than other forms of metal, the use of powders is not essential. Metal salts that are soluble in water or in aqueous mineral acids are used. When an alloy is desired, the metal proportions of the various metals in the subsequently formed salt, oxide, or hydroxide solid can be calculated on the basis of the starting materials, or the solids can be adjusted as the alloy is being manufactured. May be sampled and analyzed for metal proportions. The metal component can be dissolved in any water-soluble acid. Examples of acids include mineral acids and organic acids such as acetic acid and formic acid. Hydrochloric acid is particularly preferred due to its cost and availability.
金属源が酸水溶液に溶解された後、生成する溶液は、水
を蒸発するべく十分に加熱を施される。After the metal source is dissolved in the aqueous acid solution, the resulting solution is heated sufficiently to evaporate the water.
金属化合物、例えば酸化物、水酸化物、硫酸塩、硝酸塩
、塩化物等が、成るｐＨ条件下で溶液から析出沈殿する
。固体材料を生成する水性相から分離してもよいし或い
は蒸発を継続してもよい。蒸発の継続は、金属化合物か
ら成る残渣粒の形成をもたらす。幾つかの場合、蒸発が
大気中で為されるとき、金属化合物は、水酸化物、酸化
物、或いは金属の鉱酸塩と金属水酸化物乃至酸化物との
混合物となろう。残渣は凝集状態となりそして過大寸法
の粒を含んでいよう。材料の平均粒寸は、ミリング、粉
砕、或いは他の従来からの粒減寸方法によって一般に約
２０ｊＬｍ未満に減寸されつる。Metal compounds, such as oxides, hydroxides, sulfates, nitrates, chlorides, etc., precipitate out of solution under the pH conditions. The solid material may be separated from the resulting aqueous phase or evaporation may continue. Continuation of evaporation results in the formation of residual grains consisting of metal compounds. In some cases, when the evaporation is done in the atmosphere, the metal compound will be a hydroxide, oxide, or a mixture of a mineral salt of the metal and a metal hydroxide or oxide. The residue will be agglomerated and contain oversized grains. The average particle size of the material is generally reduced to less than about 20 lm by milling, grinding, or other conventional particle size reduction methods.
粒が所望寸法に減寸された後、それらは塩の還元温度を
越え且つ粒中の金属の融点以下の温度で還元性雰囲気に
おいて加熱される。温度は水和水及び陰イオンを放出す
るに十分のものである。もし塩酸が使用されそして水和
水が存在すると、生成する湿った塩酸蒸発煙は非常に腐
食性が強いものであり従って適当な設備構成材料が使用
されねばならない。使用される温度は、そこに含まれる
金属のいずれの融点よりも低く且つ元の分子を還元しそ
してそしてその陽イオン部分のみを残すに充分高いもの
とされる。大半の場合、少なくとも約５００℃の温度が
化合物を還元するのに必要とされる。約５００℃より低
い温度は還元を不十分とし、金属の融点を越える温度は
大きな融着凝集物をもたらす。１種を越える金属が存在
する場合には、生成する多金属粒子は様々な金属成分の
固溶体として或いは金属間化合物として結合乃至組合わ
されている可能性がある。いずれの場合も、各粒子全体
を通して金属缶々の均一な分布が存在する。生成する粒
子は一般に形状において不整である。還元段階中粒凝集
が起こると、例えば２０μｍ未満の所望の平均粒寸を実
現し、そして少なくとも５０％が約２０μｍ未満である
ようにするために従来型式のミリング、粉砕等による粒
寸法の減寸が為されつる。After the grains are reduced to the desired size, they are heated in a reducing atmosphere at a temperature above the reducing temperature of the salt and below the melting point of the metal in the grains. The temperature is sufficient to release water of hydration and anions. If hydrochloric acid is used and water of hydration is present, the resulting wet hydrochloric acid evaporation fumes are highly corrosive and therefore appropriate equipment construction materials must be used. The temperature used will be below the melting point of any of the metals involved and high enough to reduce the original molecule and leave only its cationic portion. In most cases, temperatures of at least about 500°C are required to reduce the compound. Temperatures below about 500° C. result in insufficient reduction, and temperatures above the melting point of the metal result in large fused agglomerates. If more than one metal is present, the resulting multimetallic particles may be combined or combined as a solid solution of various metal components or as an intermetallic compound. In either case, there is a uniform distribution of metal cans throughout each particle. The particles produced are generally irregular in shape. Once particle agglomeration occurs during the reduction stage, grain size reduction by conventional milling, grinding, etc. to achieve the desired average particle size, e.g., less than 20 μm, and so that at least 50% are less than about 20 μm. is done.
本発明の粉末調製において、少なくとも部分的に溶融し
た金属液滴の高速流れが形成される。こうした流れは、
燃焼溶射やプラズマ溶射のような任意の熱溶射（サーマ
ルスプレイング）技術により形成されつる。個々の粒は
完全に溶融してもよい（これが好ましい方法である）が
、幾つかの場合には後に球状粒形成を可能ならしめるに
十分の表面溶融だけでも満足しつるものである。代表的
に、液滴の速度は約Ｌｏｏｍ／秒を越える、一層代表的
には２５０ｍ／秒を越えるものとされる。In the powder preparation of the present invention, a high velocity stream of at least partially molten metal droplets is formed. This trend is
Vine formed by any thermal spraying technique such as combustion spraying or plasma spraying. The individual grains may be completely melted (this is the preferred method), but in some cases it may be sufficient to have only sufficient surface melting to allow subsequent spherical grain formation. Typically, the droplet velocity will be greater than about loom/second, more typically greater than 250 m/second.
９００ｍ／秒のオーダ或いはそれ以上の速度も、真空中
での溶射を含めてこれら速度を有利とするある種の条件
下では実現されつる。Velocities on the order of 900 m/sec or more can be achieved under certain conditions that favor these speeds, including thermal spraying in a vacuum.
本発明の好ましいプロセスにおいて、粉末は熱溶射装置
を通して給送される。供給粉末はキャリヤガスに連行さ
れそして後高温反応器を通して送られる。反応器内の温
度は好ましくは金属粉末の最大融点成分の融点を越えそ
して一層好ましくは反応器内で比較的短い滞留時間を可
能ならしめるよう材料の最大融点成分の融点をかなり越
えるものとされる。In a preferred process of the invention, powder is fed through a thermal spray device. The feed powder is entrained in a carrier gas and then passed through a high temperature reactor. The temperature within the reactor preferably exceeds the melting point of the highest melting point component of the metal powder and more preferably significantly exceeds the melting point of the highest melting point component of the material to allow for relatively short residence times within the reactor. .
分散状態で連行される溶融金属液滴の流れは、従来型式
のプラズマジェットトーチ或いは銃装置により生成され
つる。一般に、金属粉末源は、推進ガス源に接続される
。推進ガスと粉末を混合しそして推進ガスを同伴粉末と
共にプラズマ溶射装置と連通ずる導管を通して推進する
ための手段が設けられる。アーク型装置においては、連
行粉末は、ノズル中央を通して穿孔されたノズル通路と
連通しそしてそれと同心である渦巻室に給送される。ア
ーク型プラズマ装置においては、電気アークがノズル通
路の内壁と通路内に存在する電極との間に維持される。The dispersed stream of molten metal droplets is produced by a conventional plasma jet torch or gun device. Generally, a source of metal powder is connected to a source of propellant gas. Means is provided for mixing the propellant gas and the powder and driving the propellant gas along with the entrained powder through a conduit communicating with the plasma spray apparatus. In arc-type devices, the entrained powder is fed into a vortex chamber that communicates with and is concentric with a nozzle passage drilled through the center of the nozzle. In arc-type plasma devices, an electric arc is maintained between the inner wall of the nozzle passageway and an electrode located within the passageway.
電極はノズル通路より小さな直径を有し且つそれと同心
であるので、ガスはプラズマジェットの形でノズルから
放出される。電源は通常は、比較的低い電圧で非常に大
きな電流を流すのに適したＤＣ源である。アーク電力の
大きさとガス流量を調節することによって、トーチ温度
は５５００℃から１５．０００℃に至るまでの範囲をと
りつる。装置は一般に、噴射される粉末の融点と使用さ
れるガスに応じて調節される。低めの融点の粉末が窒素
のような不活性ガスと共に使用されるときには電極はノ
ズル内で引っ込められ、他方高めの融点の粉末がアルゴ
ンのような不活性ガスと共に使用されるときには電極は
ノズル内部でもっと充分に伸長されつる。Since the electrode has a smaller diameter than the nozzle passage and is concentric with it, gas is ejected from the nozzle in the form of a plasma jet. Power supplies are typically DC sources suitable for drawing very large currents at relatively low voltages. By adjusting the arc power magnitude and gas flow rate, the torch temperature can range from 5500°C to 15,000°C. The equipment is generally adjusted depending on the melting point of the powder being injected and the gas used. When a lower melting point powder is used with an inert gas such as nitrogen, the electrode is retracted within the nozzle, while when a higher melting point powder is used with an inert gas such as argon, the electrode is retracted inside the nozzle. The vines are fully extended.
誘導型プラズマ溶射装置においては、不活性ガスに連行
される金属粉末はガス流れ中に電圧を発生せしめるよう
に強い磁場を通して高速で流される。電源は、１０，０
ＯＯＡのオーダの非常に高い電流を流せるものである。In an induced plasma spray system, metal powder entrained in an inert gas is forced through a strong magnetic field at high velocity to create a voltage in the gas flow. The power supply is 10,0
It is capable of passing a very high current on the order of OOA.
但し、電圧は１０ｖ程度と比較的低く為し得る。こうし
た電流は、非常に強い直接磁場を創成しそしてプラズマ
を発生せしめるのに必要とされる。こうしたプラズマ装
置は、プラズマ発生の開始を助成する手段やノズル周囲
の環状室の形態でのトーチ冷却手段を追加的に装備し得
る。However, the voltage can be relatively low, about 10V. These currents are required to create a very strong direct magnetic field and generate a plasma. Such a plasma device may additionally be equipped with means for assisting in the initiation of plasma generation and means for cooling the torch in the form of an annular chamber around the nozzle.
プラズマプロセスにおいて、トーチ内でイオン化された
気体は、ノズルを出る際にイオン化熱を回復して高熱火
炎を創成する。一般に、プラズマ溶射装置を通しての気
体の流れは少なくとも音速に近い速度でもたらされる。In plasma processes, the ionized gas within the torch recovers its ionization heat and creates a high-temperature flame as it exits the nozzle. Generally, the gas flow through the plasma spray device is provided at a velocity at least close to the speed of sound.
代表的トーチは、スロートまで下流方向に収斂する収斂
部分を具備する導管手段を備える。収斂部分は隣り合う
出口開口と連通し、出口開口からのプラズマの放出がも
たらされる。A typical torch includes conduit means with a converging portion that converges downstream to the throat. The converging portions communicate with adjacent exit apertures, resulting in ejection of plasma from the exit apertures.
ノズルを通して高圧燃料ガスを流送する酸素−アセチレ
ン型のような他の型式のトーチもまた使用し得る。粉末
は吸引作用により気体中に導入されつる。燃料はノズル
出口において着火されて高温火炎を提供する。Other types of torches such as oxy-acetylene types that flow high pressure fuel gas through the nozzle may also be used. The powder is introduced into the gas by suction. Fuel is ignited at the nozzle outlet to provide a high temperature flame.
好ましくは、トーチに対して使用される粉末は寸法及び
組成において一様とすべきである。比較的狭い寸法分布
が所望される。何故なら、設定火炎条件下で最大粒子は
完全には溶融せず他方最小粒子は蒸発点まで加熱される
恐れがあるからである。不完全な溶融は生成物の一様性
にとって有害であり他方蒸発と分解はプロセス効率を減
じる。Preferably, the powder used for the torch should be uniform in size and composition. A relatively narrow size distribution is desired. This is because under the set flame conditions the largest particles may not completely melt, while the smallest particles may be heated to their vaporization point. Incomplete melting is detrimental to product uniformity, while evaporation and decomposition reduce process efficiency.
代表的に、本発明のプラズマ給送粉末の寸法範囲は、粒
の８０％が約１５μｍ直径範囲内に入るようなものであ
る。Typically, the size range of the plasma-delivered powders of the present invention is such that 80% of the particles fall within the approximately 15 μm diameter range.
ノズルから噴出する溶融金属液滴連行流れは外方に膨張
する傾向があるので、流れ中の液滴の密度はノズルから
の距離が増大するにつれて減少する。表面に衝突するに
先立って、流れは代表的に気体雰囲気を通過し、該雰囲
気は液滴な凝固しそして液滴速度を減じる。雰囲気が真
空に近い程、冷却及び速度損失は小さくなる。液滴が冷
却及び凝固中液滴形態に留まるようにノズルを周囲の表
面から充分に遠くに配置することが好ましい。もしノズ
ルが表面に接近しすぎると、液滴は凝固前にそこに衝突
して歪曲する。Since the entrained stream of molten metal droplets ejecting from the nozzle tends to expand outward, the density of the droplets in the stream decreases as the distance from the nozzle increases. Prior to impinging on a surface, the flow typically passes through a gaseous atmosphere that causes the droplets to solidify and reduce droplet velocity. The closer the atmosphere is to vacuum, the lower the cooling and speed losses. Preferably, the nozzle is located sufficiently far from the surrounding surface so that the droplets remain in droplet form during cooling and solidification. If the nozzle is too close to a surface, the droplets will impact and become distorted before solidifying.
溶融粒子の流れは冷却流体中に差し向けることが出来る
。冷却流体は代表的に、溶融粒子及びプラズマガスによ
り加熱されそして気化する冷却流体を補給するための入
り口を有する室内に配置される。流体は液体形態で設け
られそして急速凝固過程中気体状態に気化される。出口
は好ましくは圧力逃し弁の形態をとる。排出気体は補集
タンクに戻されそして再使用のため液化される。A stream of molten particles can be directed into a cooling fluid. The cooling fluid is typically located in a chamber having an inlet for replenishing the cooling fluid, which is heated and vaporized by the molten particles and plasma gas. The fluid is provided in liquid form and is vaporized to a gaseous state during a rapid solidification process. The outlet preferably takes the form of a pressure relief valve. Exhaust gas is returned to the collection tank and liquefied for reuse.
粒子冷却流体の選択はどういう結果が所望されるかに依
存する。大きな冷却能が所望されるのなら、高い熱容量
を有する冷却流体を用意することが望ましい。生成物の
汚染が問題となるなら、非引火性で且つ非反応性の不活
性冷却流体が望まれよう。別の場合には、粉末を改質す
るのに反応性雰囲気が望まれることもあろう。アルゴン
及び窒素が好ましい非反応性冷却流体である。酸化物を
還元しそして所望されざる反応から保護するために成る
場合には水素が好ましいであろう。液体窒素は窒化物の
形成を増進しよう。酸化物の形成が所望されるのなら、
選択的酸化条件下での空気が適当な冷却流体である。The choice of particle cooling fluid depends on what result is desired. If a large cooling capacity is desired, it is desirable to provide a cooling fluid with a high heat capacity. If product contamination is a concern, a non-flammable and non-reactive inert cooling fluid may be desired. In other cases, a reactive atmosphere may be desired to modify the powder. Argon and nitrogen are preferred non-reactive cooling fluids. Hydrogen may be preferred if the purpose is to reduce the oxide and protect it from undesired reactions. Liquid nitrogen will enhance nitride formation. If oxide formation is desired,
Air under selective oxidizing conditions is a suitable cooling fluid.
溶融用のプラズマは同一ガスの多くから形成されるから
、溶融系と冷却流体とは適合するよう選択されつる。Since the melting plasma is formed from many of the same gases, the melting system and cooling fluid are selected to be compatible.
冷却速度は、冷却流体と冷却されるべき溶融粒子の熱伝
導率、冷却されるべき流れの大きさ、個々の液滴の寸法
、粒速度並びに液滴と冷却流体との温度差に依存する。The cooling rate depends on the thermal conductivity of the cooling fluid and the molten particles to be cooled, the size of the stream to be cooled, the size of the individual droplets, the particle velocity and the temperature difference between the droplets and the cooling fluid.
液滴の冷却速度は上記因子を調整することにより制御さ
れる。冷却速度は、液体浴表面からプラズマの距離を調
節することにより変更されつる。ノズルを浴表面に近付
ける程液滴は一層急速に冷える。The cooling rate of the droplets is controlled by adjusting the above factors. The cooling rate can be varied by adjusting the distance of the plasma from the liquid bath surface. The closer the nozzle is brought to the bath surface, the more rapidly the droplets cool.
粉末の回収は、回収室の底から収集粉末を取出すことに
より便宜良く達成される。冷却流体は、蒸発せしめても
よいし、酸化或いは所望されざる反応を防止するため所
望なら保持されつる。Powder collection is conveniently accomplished by removing the collected powder from the bottom of the collection chamber. The cooling fluid may be allowed to evaporate or may be retained if desired to prevent oxidation or other undesired reactions.
球状粉末の粒寸は主に、高温反応器中への供給物の寸法
に依存する。幾らかの高密化が起こりそして表面積は減
少し、以って見掛は粒寸は減少する。好ましい形の粒寸
測定は、マイクロメルグラフ、セディグラフ或いはマイ
クロトラックによるものである。粒の大多数は約２０μ
ｍ未満或いはもっと細かいものとなる。所望の寸法は合
金の用途に依存する。例えば、微小回路用途のような成
る場合には、約３μｍ未満のような極めて微細な材料が
所望される。The particle size of the spherical powder depends primarily on the size of the feed into the high temperature reactor. Some densification occurs and the surface area decreases, thus reducing the apparent particle size. A preferred form of particle size measurement is by Micromelgraph, Sedigraph or Microtrac. The majority of grains are about 20μ
It is less than m or even finer. The desired dimensions depend on the application of the alloy. For example, in some cases, such as microcircuit applications, very fine materials, such as less than about 3 μm, are desired.
聚朋ｊΣ別釆
本発明により製造された粉末材料は、微細であるのみな
らず、楕円状材料を実質含まずそして丸みの付いた端を
有する細長い粒を実質含まない球状である。The powder material produced in accordance with the present invention is not only fine, but also spherical, substantially free of ellipsoidal material and substantially free of elongated grains with rounded edges.
球状粒は射出成形及びプレス及び焼結操作において非球
状粒を上回る利点を有する。匹敵寸法の非球状粒と違っ
て表面積の小さな球状粒は、バインダとの混合を容易な
らしめそして脱ロウ等の洗浄を一層容易ならしめる。本
発明は、こうした球状粒を簡易に且つ確実に生成する。Spherical grains have advantages over non-spherical grains in injection molding and pressing and sintering operations. Spherical grains with a small surface area, unlike non-spherical grains of comparable size, facilitate mixing with the binder and make cleaning such as dewaxing easier. The present invention easily and reliably produces such spherical particles.
本発明の例示のために、実施例を示す。比率、割合等は
断りのないかぎり、重量に基ずく。Examples are presented to illustrate the invention. Ratios, percentages, etc. are based on weight unless otherwise specified.
Ｘ巖胴
約７８０部の鉄粉末と約１８０部のニッケル粉末を、ガ
ラス内張攪拌機付き反応器を使用して約４０００部の１
ＯＮのＨＣｌ中に溶解した。モリブデン酸アンモニウム
の溶液として約４０部のモリブデンをこれに加えた。About 780 parts of iron powder and about 180 parts of nickel powder were mixed into about 4000 parts of nickel powder using a glass-lined reactor equipped with a stirrer.
Dissolved in HCl ON. Approximately 40 parts of molybdenum was added to this as a solution of ammonium molybdate.
水酸化アンモニウムを約６．５〜７．５のｐＨまで添加
した。鉄、ニッケル及びモリブデンは、水酸化物の緊密
な混合物として析出沈殿した。この混合物を乾燥状態に
蒸発処理した。その後、混合物を大気中で約３５０℃に
３時間加熱して、過剰の塩化アンモニウムを除去した。Ammonium hydroxide was added to a pH of about 6.5-7.5. Iron, nickel and molybdenum precipitated out as an intimate mixture of hydroxides. This mixture was evaporated to dryness. The mixture was then heated in air to about 350° C. for 3 hours to remove excess ammonium chloride.
この混合物をハンマーミルにかけて、粒子の５０％を越
える粉末が約５０μｍより小さくそして１００μｍより
大きな粒が存在しないような粉末を生成した。これら粉
砕粒子を水素還元雰囲気中で約７５０℃の温度において
約３時間加熱した。７８％鉄、１８％ニッケル及び４％
モリブデンを含有する細かい粒が形成された。This mixture was hammer milled to produce a powder in which more than 50% of the particles were smaller than about 50 μm and no particles were larger than 100 μm. These ground particles were heated in a hydrogen reducing atmosphere at a temperature of about 750° C. for about 3 hours. 78% iron, 18% nickel and 4%
Fine grains containing molybdenum were formed.
このＦｅ−Ｎｉ−Ｍｏ粉末粒子をアルゴンキャリヤガス
に連行せしめた。これら粒子は、メトコ９ＭＢプラズマ
銃に約１０１ｂ／時間の流量で送給された。ガスは約６
ｆｔ３／時間で送給した。プラズマガス（Ａｒ中）１
２）は約７０ ｆｔ３／時間で送給した。トーチ電力は
約５０Ｖ及び４００Ａにおいて約２０ＫＷであった。溶
融液滴を不活性ガスを収納する室内に搬出した。生成し
た粉末は２種の部分な含んだ。大部分は球状の再凝固粒
子から成った。小部分は部分溶融しそして再凝固した表
面を有する粒子から成った。The Fe-Ni-Mo powder particles were entrained in an argon carrier gas. These particles were delivered to a Metco 9MB plasma gun at a flow rate of approximately 101 b/hr. Gas is about 6
It was delivered at ft3/hour. Plasma gas (in Ar) 1
2) was delivered at approximately 70 ft3/hour. Torch power was about 20 KW at about 50V and 400A. The molten droplets were transported into a chamber containing an inert gas. The resulting powder contained two parts. The majority consisted of spherical resolidified particles. The small portion consisted of particles with a partially melted and resolidified surface.
以上、本発明について具体的に説明したが、本発明の範
囲内で多くの変更を為しうることを銘記されたい。Although the invention has been specifically described above, it should be remembered that many changes can be made within the scope of the invention.
Claims (1)
成する段階と、（ｂ）前記金属の塩、前記金属の酸化物
及び前記金属の水酸化物並びにそれらの混合物から成る
群から選択される還元性固体金属質材料を形成する段階
と、（ｃ）前記材料を還元して金属粉末粒子を形成する
段階と、（ｄ）前記金属粉末粒子の少なくとも一部をキ
ャリヤガスに連行せしめる段階と、（ｅ）前記連行粒子
及びキャリヤガスを高温帯域に給送しそして粒子の少な
くとも約５０重量％を溶融しそして液滴を形成するに十
分の時間前記帯域に粒子を維持する段階と、（ｆ）前記
液滴を冷却して、実質球状を有しそして平均粒子寸法が
２０μｍ未満である金属粒子を形成する段階とを包含す
る金属粉末製造方法。 ２）水溶液が水溶性の酸を含有する特許請求の範囲第１
項記載の方法。 ３）還元性固体材料が溶液からの水の蒸発により形成さ
れる特許請求の範囲第２項記載の方法。 ４）還元性固体材料が固体を形成するようｐＨを調整し
そして該固体を生成水性相から分離することにより形成
される特許請求の範囲第２項記載の方法。 ５）溶液が塩酸、硫酸及び硝酸から成る群から選択され
る鉱酸を含有する特許請求の範囲第２項記載の方法。 ６）鉱酸が塩酸である特許請求の範囲第５項記載の方法
。 ７）段階（ｂ）により生成された材料が還元段階（ｃ）
に先立って粒寸減縮段階を施される特許請求の範囲第１
項記載の方法。 ８）段階（ｃ）からの粉末粒子が連行段階（ｄ）に先立
って粒寸減縮段階を施される特許請求の範囲第１項記載
の方法。 ９）高温帯域がプラズマトーチにより創成される特許請
求の範囲第１項記載の方法。 １０）キャリヤガスが不活性ガスである特許請求の範囲
第１項記載の方法。 １１）金属粒子の実質すべてが溶融される特許請求の範
囲第１項記載の方法。Claims: 1) (a) forming an aqueous solution containing at least one metal; and (b) salts of said metal, oxides of said metal and hydroxides of said metal, and mixtures thereof. (c) reducing said material to form metal powder particles; and (d) converting at least a portion of said metal powder particles into a carrier. (e) delivering the entrained particles and a carrier gas to a high temperature zone and maintaining the particles in the zone for a sufficient time to melt at least about 50% by weight of the particles and form droplets; and (f) cooling the droplets to form metal particles having a substantially spherical shape and an average particle size of less than 20 μm. 2) Claim 1 in which the aqueous solution contains a water-soluble acid
The method described in section. 3) A method according to claim 2, wherein the reducible solid material is formed by evaporation of water from a solution. 4) The method of claim 2, wherein the reducible solid material is formed by adjusting the pH to form a solid and separating the solid from the resulting aqueous phase. 5) A method according to claim 2, wherein the solution contains a mineral acid selected from the group consisting of hydrochloric acid, sulfuric acid and nitric acid. 6) The method according to claim 5, wherein the mineral acid is hydrochloric acid. 7) The material produced by step (b) undergoes reduction step (c)
Claim 1, which is subjected to a particle size reduction step prior to
The method described in section. 8) A method according to claim 1, wherein the powder particles from step (c) are subjected to a particle size reduction step prior to entrainment step (d). 9) A method according to claim 1, wherein the high temperature zone is created by a plasma torch. 10) The method according to claim 1, wherein the carrier gas is an inert gas. 11) The method according to claim 1, wherein substantially all of the metal particles are melted.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US5455787A | 1987-05-27 | 1987-05-27 | |
| US054557 | 1997-08-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63307203A true JPS63307203A (en) | 1988-12-14 |
Family
ID=21991929
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63126049A Pending JPS63307203A (en) | 1987-05-27 | 1988-05-25 | Wet metallurgical method for producing finely divided or spherical metal powder |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0292798A3 (en) |
| JP (1) | JPS63307203A (en) |
| CA (1) | CA1330625C (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01259101A (en) * | 1988-04-08 | 1989-10-16 | Nippon Steel Corp | Manufacture of ferrous spherical particle |
| JP2021503041A (en) * | 2017-11-14 | 2021-02-04 | パイロジェネシス・カナダ・インコーポレーテッド | Methods and equipment for producing fine spherical powders from coarse and angular powder feedstocks. |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5173108A (en) * | 1989-03-21 | 1992-12-22 | Gte Products Corporation | Method for controlling the oxygen content in agglomerated molybdenum powders |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3663667A (en) * | 1970-02-13 | 1972-05-16 | Sylvania Electric Prod | Process for producing metal powders |
| US3974245A (en) * | 1973-12-17 | 1976-08-10 | Gte Sylvania Incorporated | Process for producing free flowing powder and product |
| DE3211718A1 (en) * | 1981-04-01 | 1982-11-04 | National-Standard Co., 49120 Niles, Mich. | METHOD FOR PRODUCING METAL BODIES OF REGULATED DENSITY AND THE USE THEREOF FOR GENERATING AN ELECTROSTATIC DEVELOPER |
| JPS58224103A (en) * | 1982-06-21 | 1983-12-26 | Mitsui Mining & Smelting Co Ltd | Production of fine copper powder |
| JPS5985804A (en) * | 1982-11-09 | 1984-05-17 | Shintou Bureetaa Kk | Spheroidal iron powder |
-
1988
- 1988-05-11 EP EP88107645A patent/EP0292798A3/en not_active Withdrawn
- 1988-05-19 CA CA000567214A patent/CA1330625C/en not_active Expired - Fee Related
- 1988-05-25 JP JP63126049A patent/JPS63307203A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01259101A (en) * | 1988-04-08 | 1989-10-16 | Nippon Steel Corp | Manufacture of ferrous spherical particle |
| JP2021503041A (en) * | 2017-11-14 | 2021-02-04 | パイロジェネシス・カナダ・インコーポレーテッド | Methods and equipment for producing fine spherical powders from coarse and angular powder feedstocks. |
Also Published As
| Publication number | Publication date |
|---|---|
| CA1330625C (en) | 1994-07-12 |
| EP0292798A3 (en) | 1989-08-30 |
| EP0292798A2 (en) | 1988-11-30 |
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