α污染层对ZTC4钛合金铸态试样冲击性能的影响

Effects of the Contamination of α Layer on the Impact Properties of ZTC4 Titanium Casting Samples

在表征ZTC4钛合金铸件污染层的基础上,分析了α污染层对ZTC4钛合金铸态试样冲击性能的影响情况。实验结果表明,α污染层主要是由钛液与铸型材料界面反应产生的,为粗大的α片层组织。α污染层的存在对ZTC4钛合金铸态试样冲击性能影响显著,当铸态试样含α污染层一侧受冲击时,冲击强度下降了近9%;而当铸态试样含α污染层一侧的背面受冲击时,冲击强度下降了近80%,α污染层严重恶化了ZTC4钛合金铸态试样的冲击性能。

The surface contamination layers of ZTC4 titanium castings were characterized and the effects of α layer existence on impact properties of ZTC4 titanium castings were investigated. The results show that the microstructure of α layer is coarse lamellar, which is generated due to the interface reaction between titanium liquid and mold materials. The α layer has great influence on the impact properties of ZTC4 titanium castings. By comparison with that of the casting sample without αlayer, as the side with α layer in castings sample is impacted, the decrease of impact strength of the casting sample is about 9%, while the opposite side in castings sample is impacted, the decrease of impact strength of the casting sample is about 80%. That is, α layer does harm to impact properties of ZTC4 casting sample seriously.