热加工方式对双合金结合界面组织与力学性能的影响

Effect of hot working method on interfacial microstructures and mechanical properties of dual alloy

对比电子束焊接和线性摩檫焊接的Ti_2AlNb/TCll双合金试样在焊接态与等温变形和热处理耦合作用后结合界面的组织与力学性能。结果表明:等温变形和热处理耦合作用可细化电子束焊接Ti_2AlNb/TC11双合金结合界面的晶粒粒径,显著提高冲击韧性值约72%;等温变形和热处理耦合作用除可明显改变均匀线性摩擦焊接Ti_2AlNb/TC11双合金结合界面的化学成分外,还可平缓地连续过渡为改变界面区域突变的显微组织,并大幅提高结合界面的抗拉强度和塑性。

The interfacial microstructure and mechanical properties of Ti2AlNb/TC11 dual alloy jointed by electron beam weld and linear friction weld before and after near isothermal deformation and heat treatment were investigated. The results show that the grain size on interface of sample welded by the electron beam weld is refined obviously by near isothermal deformation and heat treatment couple. The chemical components at the interface of dual Ti2AlNb/TC11 alloy are changed by isothermal deformation and heat couple treatment. The microstructure transform step by step through the weld line due to diffusion of element and re-construction of crystal lattice, the tensile strength and plasticity increase obviously after near isothermal deformation followed by solution and aging treatment.