异种钢焊接接头加热后碳迁移区力学性能的变化规律

Mechanical Properties of Carbon Migration Zone of Dissimilar Steel Welded Joints after Heating

摘要: 对奥氏体焊缝与珠光体耐热钢母材的异种钢焊接接头,采用热处理加速碳迁移法,分析了加热温度T和保温时间t对接头增碳层厚度h的影响规律和由此而引起的该区力学性能(即缺口拉伸强度σ_b、冲击韧性α_KU和冷弯角α)的变化。通过非线性回归分析,建立了h、α_b、α_KU和α对加热温度T和保温时间t的数学模型。理论分析与试验结果拟合良好。随着加热温度的提高和加热时间的延长,h增大而α_b、α_KU和α减小。据此规律可分析接头长期高温运行后碳迁移区的力学性能,进而估算接头的使用寿命。

Abstract: Influence of heating temperature and time on the thickness of carbonized layer and the mechanical properties of carbon migration zone for dissimilar steel welded joints were investigated.The mathematical models of carbonized layer thickness(h),tensile strength(σ_b),impact toughness (α_KU) and bending angle(α) to heating temperature(Τ) and time(t) were created by means of nonlinear regressive analysis method.Theoretical analysis agreed with the experimental results.With the increased of heating temperature and time,h increased while σ_b,α_KU and α decreased.