アトマイズ法により作製された亜共晶Ｆｅ‐Ｃ系鋳鉄粉末のパルス通電焼結特性 ＩＩＩ アトマイズ鋳鉄粉末多孔質焼結体の強度特性

Abstract

The relationships between the bending strength and the relative density in the atomized cast-iron porous sintered bodies, which were made by the vacuum sintering method and the pulse electric current sintering method, were studied. The results were as follows:(1) In the vacuum sintered body, the bending strength depended on the carbon content of powder. The bending strength of both the relative density over 65% of Fe-2.46mass%C compact and the relative density over 90% of Fe-3.96mass%C compact were dependent on the particle size, and the bending strength of the sintered body made from small size powder was larger than that of made from large size powder.(2) In the pulse electric current sintered body, the bending strength did not depend on the particle size, the carbon content and the sintering condition.(3) In the relative density range from 60% to 90%, the bending strength of the vacuum sintered body was larger than that of the pulse electric current sintered body. Over the relative density 90%, the bending strength of the pulse electric current sintered body was larger than that of the vacuum sintered body. In the low relative density range (60-90%), the bending strength was affected by the pore shape. However, in the high relative density range (90%-), the bending strength was influenced by the size of Fe3C.