| 摘要 |
<p>PURPOSE:To obtain superior mechanical strength without resintering, by subjecting the powdery compact made of steel containing a prescribed amount of an easily oxidizable alloy element to vacuum sintering and by performing hot forging at a prescribed temperature. CONSTITUTION:Powder of steel containing 0.8-10wt% one or more kinds of easily oxidizable alloy elements selected among Mn, Cr, Si, and V is compacted. This powder is sintered at 1,200 deg.C for 30min in 10<-3>Torr vacuum, thereafter hot forging is carried out in an atmosphere of inert gas at 900-1,200 deg.C. This method accelerates the sintering remarkably, increases binding strength and reduces internal inclusions, suppressing the occurrence of microcracking. Therefore, superior mechanical strength is obtained even when resintering is not carried out after the forging.</p> |
