Ag-BASED METAL POWDER, Cu-BASED METAL POWDER, AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide metal powder having a small dimensional change rate, satisfactory ductility and low flocculation properties. SOLUTION: Using a water atomization process including: a stage where an annular jet slit 2 of jetting the jet water flow of a water jet curtain is arranged downward, and a molten metal flow is made to flow down along a central axis; and a stage where water is jetted in a direction having a lowering angleθand a swinging angleωin such a manner that a constricted cavity 7 of the water jet curtain through which the jet water flow does not pass is formed, wherein, the jet water flow 12 of one sheet hyperbolic water jet curtain is generated so as to produce a metal powder, the lowering angleθis controlled to 0 to 30°, the swinging angleωis controlled to 1 to 20°, the pressure of the water is controlled to 90 to 150 MPa, and the flow rate of the water is controlled to 300 to 800 L/min so as to obtain the metal powder having a 50% diameter of 0.1 to 5μm, sphericity of 0.6 to 0.9, a grain size width index of≤1, a specific oxygen content of 0.5 to 7 mg/m2, and a specific water content of≤1 mg/m2. COPYRIGHT: (C)2007,JPO&INPIT