基于钛合金微区真实组织的力学性能数值模拟研究

Research on Numerical Simulation of Mechanical Properties Based on Real Microstructure of Titanium Alloy

基于TC11钛合金微区真实组织实现了其微区力学性能的数值模拟。探讨了基于微区组织实现其力学性能模拟的方法及关键步骤,采用金相测试并通过软件处理获取了微区组织形貌,采用纳米压痕测试实验和数值计算获得微区相组成的材料参数,采用Abaqus软件实现了微区拉伸加载过程的有限元数值模拟。结果表明,TC11钛合金不同的相结构具有不同的弹性模量和屈服强度,其中,片层α+β相的弹性模量和屈服强度最小,等轴α相的弹性模量和屈服强度最大,等轴α与片层组织边界处的弹性模量和屈服强度居中。2000N/m均布载荷的拉伸加载条件下,数值计算得到了TC11钛合金微区组织的屈服强度为1020 MPa,抗拉强度为1285 MPa;且在拉伸加载过程中等轴α相先沿x方向变形,随后在片层α+β相的变形协调下发生部分转动变为沿45°方向变形,应力集中和断裂发生在等轴α相和片层α+β相边界位置。

Based on the real microstructure of TC11 titanium alloy, the numerical simulation of its micro mechanical properties was realized. The method and key steps of mechanical property simulation based on micro region structure were discussed. The micro region structure morphology was obtained by metallographic test and software processing. The material parameters of micro region phase composition were obtained by nano indentation test experiment and numerical calculation.And the finite element numerical simulation of micro region tensile loading process was realized by ABAQUS software. The results show that different phase structures of TC11 titanium alloy have different elastic modulus and yield strength. The elastic modulus and yield strength of the lamellar α +β phase are the smallest. The elastic modulus and yield strength of equiaxed α are the largest;And the elastic modulus and yield strength of the boundary between equiaxed α with lamellar structure are in the middle. At the same time, under the tensile loading boundary condition of 2000 N/m uniformly distributed load, the numerical yield strength of TC11 structure is 1020MPa and the numerical tensile strength is 1285 MPa. Under tensile loading, Equiaxed α phase deforms in the x direction first. And then under the coordination of lamella α+β phase deformation,the equiaxed α phase partial rotates and becomes deforming along the 45° direction. The stress concentration and fracture occur in equiaxed α phase and lamellar α+β phase boundary.