초록 ▼

A powdered material and a process for producing the material are disclosed. The powdered material consists essentially of iron group based and chromium based spherical particles. The material is essentially free of elliptical shaped material and elongated particles having rounded ends. The material

A powdered material and a process for producing the material are disclosed. The powdered material consists essentially of iron group based and chromium based spherical particles. The material is essentially free of elliptical shaped material and elongated particles having rounded ends. The material has a particle size of less than about 20 micrometers. The process for making the spherical particles involves mechanically reducing the size of a starting material to produce a finer powder the major portion of which has a particle size of less than about 20 micrometers. The finer powder is entrained in a carrier gas and passed through a high temperature zone at a temperature above the melting point of the powder to melt at least about 50% by weight of the powder and form the spherical particles of the melted portion. The powder is then directly solidified.

대표청구항 ▼

A process comprising: (a) mechanically reducing the size of a material selected from the group consisting of iron group based and chromium based materials to produce a finer powder, the major portion of which has a particle size of less than about 20 micrometers; (b) entraining said finer powder in

A process comprising: (a) mechanically reducing the size of a material selected from the group consisting of iron group based and chromium based materials to produce a finer powder, the major portion of which has a particle size of less than about 20 micrometers; (b) entraining said finer powder in a carrier gas and passing said powder through a high temperature zone at a temperature above the melting point of said finer powder, said temperature being from about 5500°C. to about 17,000°C., said temperature being created by a plasma jet, to melt at least about 50% by weight of said finer powder to form essentially fine spherical particles of said melted portion; and (c) rapidly and directly resolidifying the resulting high temperature treated material, while said material is in flight, to form fine spherical particles having a particle size of less than about 20 micrometers in diameter, said particles being essentially free of elliptical shaped material and essentially free of elongated particles having rounded ends.