论文部分内容阅读
基于ANSYS有限元对锅炉用Q390钢多道次气体保护焊接温度场进行数值模拟,获得了热循环曲线、峰值温度与组织状态的变化规律,结合SH-CCT曲线,预测了热影响区宽度和组织分布,将结果与相同焊接条件下试验数据对比。结果表明:模拟温度分布与实测数据吻合良好;模拟热影响区宽度为3.3 mm,实测位置的峰值温度为1189.54℃,冷却后得到贝氏体和马氏体混合组织;采用药芯焊丝CHT711的焊缝为铁素体、贝氏体和珠光体组织,热影响区以贝氏体组织为主;拉伸断裂位置在母材,断口呈杯锥形的韧窝断裂,其力学指标满足工程要求。
Based on ANSYS finite element method, the temperature field of Q390 steel multi-pass gas shielded welding for boilers was numerically simulated. The variation of thermal cycling curve, peak temperature and microstructure were obtained. Combined with SH-CCT curve, the width and structure of heat affected zone Distribution, the results with the same welding conditions under test data contrast. The results show that the simulation temperature distribution is in good agreement with the measured data. The width of the simulated heat-affected zone is 3.3 mm and the peak temperature at the measured position is 1189.54 ℃. After cooling, bainite and martensite mixed microstructure are obtained. The joints are mainly composed of ferrite, bainite and pearlite with bainite dominated in the heat-affected zone. The fracture site of the tensile fracture is cup-cone-shaped dimple fracture, whose mechanical indexes meet the engineering requirements.