航空用钛合金显微组织控制和力学性能关系

钛合金由于具有多样性和复杂性的固态相变特征,其组织性能关系一直都是材料科学工作者研究的热点之一。通过调整钛合金的成分配比、加工工艺以及热处理工艺参数,可以在一定范围内调整钛合金制件的组织类型与组织参数,实现强度、塑性、韧性、疲劳和疲劳裂纹扩展速率等综合性能的最佳匹配。本文在对比钛合金材料的等轴组织、双态组织、网篮组织和片层组织四种典型显微组织特征以及控制技术基础上,以航空用TC21钛合金、TC4-DT钛合金、TC32钛合金以及TB17钛合金为例综述不同显微组织特征与拉伸性能、断裂韧度、疲劳裂纹扩展速率的影响关系,为钛合金选择合适的组织参数、实现最佳的综合性能匹配和稳定批量生产提供参考依据。

Microstructure controlling technology and mechanical properties relationship of titanium alloys for aviation applications

Because of the variety and complexity of solid-state phase transformation characteristics of titanium alloys,the relationship between their microstructure and performance has always been one of the hot topics in the field of titanium alloy materials science.By adjusting the composition,processing technology and heat treatment process parameters of titanium alloys,the microstructure type and parameters of titanium alloy parts can be adjusted to a certain extent to achieve the best matches in strength,plasticity,toughness,fatigue and fatigue crack propagation rate,etc.In this paper,based on the comparison of four typical microstructure characteristics including equiaxed microstructure,bimodal microstructure,lamellar microstructure,basket weave microstructure and their thermo-mechanical controlling technologies,taking the TC21 titanium alloy,TC4-DT titanium alloy,TC32 titanium alloy and TB17 titanium alloy for aviation use as examples to review the properties of strength,plasticity,fracture toughness,fatigue life and fatigue crack propagation rate,which can provide a reference basis for reasonably choosing microstructure parameters,optimizing properties,stabilizing mass production quality of titanium alloy products.