固态相变对Fe-Co-Ni超高强度钢长臂梁构件焊接-淬火过程应力和变形的影响

Effect of Solid-State Phase Transformation on Stress and Distortion for Fe-Co-Ni Ultra-High Strength Steel Components During Welding and Vacuum Gas Quenching Processes

建立了Fe-Co-Ni超高强度钢板电子束焊热源模型和“热-冶金-力学”耦合有限元模型,通过焊缝截面形貌和残余应力的模拟结果和实测结果对比,验证了耦合有限元模型的可靠性。利用耦合有限元模型模拟了Fe-Co-Ni超高强度钢长臂梁构件的“电子束焊-真空气淬”过程,预测了在焊接-淬火过程中组织转变规律和应力与变形。研究发现,真空气淬是导致超高强度钢构件产生明显变形的主要原因,考虑固态相变的真空气淬过程模拟结果可以获得准确的变形方向和大小。

Due to its outstanding all-around performance,Fe-Co-Ni ultra-high strength steel(UHSS)is frequently used in crucial load-bearing components.The UHSS components will be significantly deformed during the welding and post-welding heat treatment operations,which makes the subsequent assembly to satisfy usage requirements a challenge.As a result,it is crucial to simulate the entire manufactur-ing process of UHSS components to investigate and comprehend the laws of stress and distortion in UHSS component weld joints throughout the manufacturing process.In this study,the“thermo-metallurgicalmechanical”coupled finite element model􀆳s accuracy is first verified,followed by the development of a heat source model for electron beam welding.The evolution of the microstructure of the weld joint,stress,and distortion in the weld joint of complex components are thus precisely predicted using the linked model throughout the production process of“electron beam welding-vacuum gas quenching”.The primary cause of the severe deformation of complex components is vacuum gas quenching.The solid-state phase transformation cannot be ignored in the simulation process of“electron beam welding-vacuum gas quenching”of the complicated components.