【摘要】 <正> 钢铁材料的回火脆和氢脆都是引入注目的问题。分别加以研究的文献相当多,得到的规律及其解释也不尽一致。本文对40Cr 钢淬火后在回火脆温度范围内回火的试样进行阴极电解充氢,研究其断裂韧性的变化规律。1 试验过程试验用材料为工业用40Cr 钢,其实测化学成分(wt%)为:C0.41,Si 0.30,Mn 0.64,Cr 0.96,S0.010,P 0.022,Ni 0.18,Cu 0.11,试样粗加工后在850℃盐浴炉加热后油冷。200～450℃回火后水冷。三点弯曲试验采用 COD 试样,尺寸为10mm×20mm×80mm。试样用线切割机开口后在高频疲劳机上预制更多还原

【Abstract】 The influence of hydrogen on 40Cr steel embrittled by temper- ing has been studied.The results indicate that the effect of hydrgen is to inc- rease the tendency of brittleness for 40Cr steel within first temperature range of tempering brittleness.However,under loading the"plasticity"is appeared at measurement of fracture toughness,and so the reducing level of fracture tough- ness at 350℃ is not maximum.It is related to increase size plastic zone of cracking top by hydrogen.更多还原