METHOD FOR PRODUCING POWDER MATERIAL

• Main Authors: YAMANAKA TOSHIFUMI, SAKAI TAKUYA, ITO YUKI, NATORI KAZUNARI, YAMAGUCHI JUMPEI, AIKAWA YOSHIHIKO
• Format: Patent
• Language: English; Japanese
• Published: 30.08.2021
• Subjects: CASTING; MAKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; PERFORMING OPERATIONS; POWDER METALLURGY; TRANSPORTING; WORKING METALLIC POWDER

To provide a method for producing a powder material capable of suppressing the inclusion of excessively generated fine particles when producing a powder material having fine particles adhered on the surface of the metal particle through a thermal plasma treatment.SOLUTION: There is provided a method for producing a powder material, including: a plasma treatment step of performing thermal plasma treatment to raw material particles M consisting of metal to produce metal particles P1 having a higher circularity than the raw material particles M and fine particles P2 and P3 which comprise at least a part of metal elements constituting the metal particles P1 and have a particle size smaller than that of the metal particles P1, and then producing plasma-treated particles P' in which at least a part of the fine particles P2 is attached to the surface of the metal particles P1; and a grain cracking step of separating and removing a part of the fine particles P3 from the surface of the metal particles P1 of the plasma-treated particles P' using shearing by an air flow to fractionate the composite particles in which the remaining fine particles P2 are attached to the surface of the metal particles P1, in this order.SELECTED DRAWING: Figure 1 【課題】熱プラズマ処理を経て、金属粒子の表面に微粒子が付着した粉末材料を製造するに際し、過剰に生成した微粒子の含有を抑制することができる粉末材料の製造方法を提供する。【解決手段】金属よりなる原料粒子Ｍに対して熱プラズマ処理を行うことで、原料粒子Ｍよりも円形度が高くなった金属粒子Ｐ１と、金属粒子Ｐ１を構成する金属元素の少なくとも一部を含み、金属粒子Ｐ１よりも小さい粒径を有する微粒子Ｐ２，Ｐ３と、を生成させ、金属粒子Ｐ１の表面に、微粒子の少なくとも一部Ｐ２が付着したプラズマ処理粒子Ｐ'を作製するプラズマ処理工程と、気流によるせん断を利用して、プラズマ処理粒子Ｐ'の金属粒子Ｐ１の表面から、微粒子の一部Ｐ３を分離して除去し、金属粒子Ｐ１の表面に残りの微粒子Ｐ２が付着した複合粒子を分取する解粒工程と、をこの順に実施する。【選択図】図１