不同热处理条件下30CrMnSiNi2A钢的组织性能研究

Microstructure and property of 30CrMnSiNi2A in different heat treatment

为考察热处理工艺对材料性能的影响,对不同回火温度下三种碳含量的30Cr Mn Si Ni2A钢的性能进行实验研究,并分析其组织和断口形貌.研究结果表明:低温回火时30Cr Mn Si Ni2A钢具有较高的强度和硬度,其内部组织为回火马氏体,断口形貌为韧窝断口;当碳含量增大,30Cr Mn Si Ni2A钢的强度也增大;随着回火温度升高,30Cr Mn Si Ni2A钢的强度和硬度逐渐下降,伸长率和断面收缩率却总体呈上升趋势,其组织向索氏体转变,断口形貌变为解理和沿晶断口,回火脆性与其内部形核有关.

To investigate the effect of heat treatment on the property of 30CrMnSiNi2A, the microstructure and fractography of 30CrMnSiNi2A with three carbon contents at different tempering temperature were analyzed. The experimental results show that the strength and rigidity of 30CrMnSiNi2A are high at low tempering temperature, of which the microstructure is tempered martensite and the fracture morphology is dimple fracture. The increase of carbon content results in increment of strength. With increasing of tempering temperature, the strength and rigidity of 30CrMnSiNi2A decrease, while the elongation and reduction of area increase in all, the microstructure transforms into sorbite structure and the fracture morphology becomes cleavage and intergranular fracture, during which the temper brittleness is related to nucleation.