摘要
研究了热等静压处理后铸态Ti46Al8Nb合金拉伸过程中的损伤．结果表明:消除了疏松后,Ti46Al8Nb合金拉伸强度的数据分散性仍然很大,表明疏松不是导致数据分散的唯一原因．在拉伸过程中不同强度试样的声发射行为有很大差异,说明其具有不同的损伤特征．断口分析和预拉伸着色实验结果证明,拉伸强度的数据分散性是合金晶粒粗大及其片层结构拉伸行为明显的各向异性所致;将预拉伸后样品表面去除约300 μm,在随后的第二次拉伸过程中声发射Kaiser效应不再出现,说明在拉伸加载初期(低应力下)该合金的损伤主要集中于近表面．
The damages of Ti46A18Nb alloy in tensile loading process were investigated. It was found that： 1） The dispersion of data of tension strength in Ti46A18Nb alloy was observed, even when the casting shrinkages had been removed, showing that shrinkages were not the only reason responsible for data dispersion. Acoustic Emission （AE） of different samples had different behaviors, which showed that samples with different strength have different damage characteristics. These results, along with the fracture surface observation and oxidation tinting after preloading, clarified that the dispersion of data of tension strength was due to the coarse grains and anisotropy of lamellar structures. 2） The Kaiser effect of this alloy was not observed when the surface layer of the samples was removed by 300 μm in depth after pre-loading. This result showed that the damages mainly locate at the surface layer in low tensile loading process.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2006年第3期235-239,共5页
Chinese Journal of Materials Research
基金
国家自然科学基金50371088资助项目.
