30CrMnSiA钢燃烧室的热处理工艺试验

Study on Heat Treatment Process of 30CrMnSiA Steel Combustion Chamber

为解决30CrMnSiA钢燃烧室旋压成形件等温淬火后硬度偏高时,可否采用回火的方法降低硬度的意见分歧,对这种燃烧室作了等温淬火、油淬+回火、等温淬火+回火3种不同热处理状态下材料机械性能的对比试验。试验结果表明:这种材料的燃烧室在等温淬火后,若硬度偏高不合格,采用回火的方法降低硬度后,其材料的冲击韧性将会大幅度下降,将远低于有关材料标准的要求。因此,对于安全系数不太高的30CrMnSiA钢燃烧室,不能允许以回火的方法来降低硬度,而应采用其他的工艺方法来降低硬度。而且不能笼统地认为燃烧室材料的抗拉强度和伸长率都合格,其冲击韧性也一定会合格。

In order to determine whether tempering can be used to lower the high hardness of spin formed parts of 30CrMnSiA steel combustion chamber after isothermal quenching. Comparison tests of material mechanical properties through three heat treatment methods, i. e. , isothermal quenching, oil quenching plus tempering, and isothermal quenching plus tempering are performed. The result shows that tempering can lower not only the hardness, but also the impact toughness on a large scale and far below the material requirement. Therefore, for those 30CrMnSiA steel combustion chambers without high assurance factor, lowing hardness should be achieved by other methods instead of tempering. Sometimes impact toughness of material is not necessary acceptable when both tensile strength and rate of elongation are qualified.