Abstract This paper conducts a comparative study on mechanical properties of LMD and forged Ti-6Al-4V, focusing on uniaxial compression, tension and shear response with different strain rates, and vibration fatigue behaviors with 45–50 Hz in frequency. The micro-observation on initial microstructures and fractures explains the mechanism of lower uniaxial strength, shorter fatigue life, and larger dispersion in fatigue life and fracture position of LMD sample compared with the forged counterpart. Initial void defects within LMD sample tend to be stress-concentration zone, further initiating fatigue cracks. The columnar β grains leads to anisotropy of fatigue life and crack propagation for LMD sample.

中文翻译：

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激光金属沉积与锻造Ti-6Al-4V合金的对比研究：单轴机械响应与振动疲劳性能

摘要 本文对LMD 和锻造Ti-6Al-4V 的力学性能进行了比较研究，重点研究了不同应变率下的单轴压缩、拉伸和剪切响应，以及频率为45-50 Hz 的振动疲劳行为。对初始显微组织和断裂的微观观察解释了与锻造试样相比，LMD 试样单轴强度较低、疲劳寿命较短、疲劳寿命和断裂位置偏差较大的机制。LMD 样品中的初始空隙缺陷往往是应力集中区，进一步引发疲劳裂纹。柱状β晶粒导致LMD样品的疲劳寿命和裂纹扩展的各向异性。