预热温度对SA387焊后残余应力和力学性能的影响

Effect of Preheating Temperature on Post Weld Residual Stress and Mechanical Properties of SA387

为了研究预热温度对SA387材料焊后力学性能和残余应力的影响,采用4种不同的预热温度分别焊接试板。对焊接完毕后的试板进行残余应力测定,发现随着预热温度的升高,焊接残余应力呈现先降低后升高的情况;通过力学性能测试和显微组织观察,发现预热温度对材料力学性能有很大影响,材料的抗拉强度和屈服强度随预热温度的升高而降低,韧性随着预热温度的升高先降低后升高。综合焊接残余应力和材料力学性能的测试结果,建议SA387 Gr11 Cl2的预热温度选择265~290℃。

In order to study the effect of preheating temperature on post weld residual stress and mechanical properties of SA387 material,four different preheating temperatures were used to weld the test plates respectively.The residual stress of the test plate after welding was measured.It is found that the welding residual stress decreases first and then increases with the increase of preheating temperature.Through mechanical property test and microstructure observation,it is found that preheating temperature has a great influence on the mechanical properties of the material.The tensile strength and yield strength of the material decrease with the increase of preheating temperature,and the toughness first decreases and then increases with the increase of preheating temperature.Based on the test results of welding residual stress and material mechanical properties,it is suggested that the preheating temperature of SA387 Gr11 Cl2 should be 265-290℃.