摘要
利用有限元分析软件ABAQUS,使用生死单元法建立冷金属过渡(CMT)电弧增材修复回火脆状态下的2.25Cr1Mo钢模型,通过试验对该模型进行验证,模拟分析了不同焊接电流、焊接电压、焊接速度在修复过程中温度场、应力场和热影响区的分布和变化规律,结果表明,模拟得到的温度、残余应力、HAZ分布曲线和试验的检测结果相吻合,验证了有限元模型的可能性,并得出结论,残余应力在温度梯度较大的地方分布较广且较大,热影响区与熔池大小、热量散布速率有关。最终通过正交试验,使用极差方差分析法得出最优参数:焊接电流160 A、焊接电压15 V、焊接速度3.2 mm/s,并模拟了预热及焊后热处理对残余应力的影响,结果表明经过焊后热处理,焊缝、热影响区的残余应力值有大幅度的降低,从266.7 MPa降低到38.1 MPa,下降了85.7%,材料的抗裂性能与耐久性等得到了提升。
Making using of the birth-death element method and the finite element analysis software ABAQUS establish a 2.25Cr-1Mo steel model in tempering brittle state with cold metal transition(CMT)WAAM repair.The simulation was verified by experiments.The distribution and variation of temperature field,stress field and heat-affected zone during the repair process of different welding currents,welding voltages and welding speeds were simulated and analyzed.The results show that,the simulated temperature distribution curve complies with the residual stress distribution curve and the measured results,which verifies the possibility of the finite element model.It is concluded that the residual stress is widely distributed and large in places with large temperature gradients.The heat affected zone is related to the size of the molten pool and the heat diffusion rate.Finally,through the orthogonal test,the optimal parameters were obtained by using the range variance analysis method:welding current 160A,welding voltage 15V and welding speed 3.2mm/s.Simulating the influence of both preheating and post-weld heat treatment on residual stress indicates that,after post-weld heat treatment,the residual stress value can be greatly reduced,from 266.7 Mpa to 38.1 Mpa,a decrease of 85.7%,and the crack resistance and durability of the material can be improved.
作者
魏世奥
赵建平
戴韬
吴怨
晋志浩
葛志强
WEI Shi-ao;ZHAO Jian-ping;DAI Tao;WU Yuan;JIN Zhi-hao;GE Zhi-qiang(School of Mechanical and Power Engineering,Nanjing Tech University;Institute of Reliability-centered Manufacturing(IRcM),Nanjing Tech University)
出处
《化工机械》
2025年第4期611-620,626,共11页
Chemical Engineering & Machinery
基金
国家重点研发计划项目(批准号:2021YFC3001804)资助的课题。
