（State Key Laboratory of Advanced Brazing Filler Metals and Technology， Zhengzhou Research Institute of Mechanical Engineering， Zhengzhou 450001， China）
Abstract：The FCuSn15 and FCuSn20 prealloyed powders prepared by multi-stage coupling atomization method were used as raw materials for hot pressing under different process conditions. The relative density， Rockwell hardness， three-point bending strength and microstructure of the sintered samples of the two kinds of copper-tin prealloyed powders were analyzed. The results show that， compared with FCuSn15， the density of FCuSn20 sintered sample is slightly lower， Rockwell hardness is increased by about 12%-15%， and three-point bending strength is decreased by 32%-36%. The surface inverse segregation of Cu-Sn prealloyed powder forms liquid phase （α＋δ） eutectoid during sintering， and the powder particles are rearranged to obtain the densest packing and the smallest total pore surface area to promote sintering densification. The FCuSn20 sintered sample has more hard and brittle δ phases， resulting in a decrease in the strength of the sintered sample.
2019, Vol. 29 
