基于焊缝高熵化的TA2与0Cr18Ni9板材TIG焊分析

Analysis on TIG welding of TA2 and 0Cr18Ni9 plate based on high entropy of weld

针对钛/钢焊接难,焊缝易产生金属间化合物导致接头力学性能不良等问题,依据焊缝金属高熵化技术思路,通过基于密度泛函理论的热力学第一性原理设计并制备出塑韧性良好的多主元Ti_(10)Fe_(29)Ni_(32)Cu_(22)V_(7)合金作为焊材,用于TA2/0Cr18Ni9薄板的TIG焊接.结果表明,使用Ti_(10)Fe_(29)Ni_(32)Cu_(22)V_(7)焊材熔焊钛/钢,所得焊接接头形貌完整,无明显焊接缺陷,焊缝金属与母材结合性良好.焊缝中心组织则由等轴晶组成,熔合区组织以柱状晶为特征,这些晶体均具有简单立方固溶体结构,有效避免了TiFe_(2),TiFe金属间化合物的形成,接头抗拉强度达到205 MPa.

In order to solve the problem of poor mechanical properties of joint caused by intermetallic compounds in the welding seam of titanium/steel,according to the high entropy technology of weld metal,the multi-component Ti_(10)Fe_(29)Ni_(32)Cu_(22)V_(7) alloy with good plasticity and toughness was designed and prepared according to the first principles of thermodynamics based on density functional theory,which was used for TIG welding of TA2/0Cr18Ni9 sheet.The results show that:using Ti_(10)Fe_(29)Ni_(32)Cu_(22)V_(7) welding material for fusion welding titanium/steel,the welding joint morphology is complete,no obvious welding defects,and the bonding between weld metal and base metal is good.The microstructure of the weld center is composed of equiaxed grains,and the microstructure of the fusion zone is characterized by columnar crystals.These crystals have a simple cubic solid solution structure,which effectively avoids the formation of intermetallic compounds.The tensile strength of the joint is high,up to 205 MPa.