正火12CrlMoV钢的回火脆化及影响因素

采用示波冲击韧性试验研究了正火１２ＣｒｌＭｏＶ钢回火脆化的行为、机制及影响因素。结果表明，基体α相的时效析出行为是导致回火脆化的主要原因，峰时效阶段沉淀出细小碳化物质点对位错的强钉扎作用使基体塑性变形能力下降，质点与基体的共格、半共格关系使基体弹性畸变能较高，冲击断裂过程为理解纹萌生控制的脆性失稳断裂。

Factors Affecting the Temper Embrittlement of Normalized Steel 12CrMoV

The temper embrittlement behavior of normalizde steel 12CrlMoV was studied by using the instrumented Charpy impact measurements.The results show that the embrittlement behavior strongly depends upon the precipitation from ferrite matrix due to tempering.In peak-aged condition,a decreasing in matrix deformation ability resulted from dead pinning of dislocations by fine carbide particles precipitated from ferrite and,a increasing in matrix elastic strain energy conducted by coherence or partial coherence correlate with embrittlement controlled by crack unstable propagation in impact fracture process.