TA15钛合金锻件裂纹分析

TA15钛合金锻件在加工过程中，发现加工表面存在裂纹。通过对裂纹形态、裂纹断口的宏微观特征、裂纹金相、材质组织及硬度等检测与分析，得出了裂纹性质及产生原因，并通过裂纹断口温色对比分析以及断口微区成分分析，获得了裂纹产生的温度范围。结果表明，TA15钛合金裂纹为锻造折叠裂纹，折叠裂纹在锻造过程中发生了扩展。裂纹主要是由于表面没有清理干净的氧化皮卷入所致。裂纹左侧棕红色断口形成温度高于800℃，右侧灰色断口形成温度不高于500℃。

Crack Analysis of TA15 Titanium Alloy Forgings

In the process of machining, a crack was found on the surface of TA15 titanium alloy forging. Based on the analysis of macro and micro features of crack and fracture, metallographic microstructure examination and hardness testing, the mode and cause of the crack were determined. The temperature range of the crack initiation stage was obtained through the analysis and contrast of fracture temperature color and micro area composition. The results show that the crack of TA15 titanium alloy is a folding crack forming during forging, and it propagated during forging. The crack was mainly caused by the involvement of the oxide skin which hadn't been cleaned up from the surface. The formation temperature of brownish red fracture on the left side of the crack is higher than 800℃, and that of the gray fracture on the right is not higher than 500℃.