A TC10 alloy casting with defect was treated by HIP process at 940-950 ℃ and 120-130 Mpa for 3-3.5 h. Microstructure of the defect was analyzed. Results show that the closing interface that is black and incontinuous line-like still remains. The black interface was observed by SEM-EDAX. Through comparing the composition between the matrix and the interface, it was revealed that the black interface was not cavities enriched in impurities, but a nonuniform interface of alloy elements. The analysis results show that the closing mechanism of casting defect in HIP is a creeping and diffusion process. When the pressure is higher than the metal creeping strength at a certain temperature, the defects are closed gradually. The longer the holding time is, the better the closing results are.%对一处已知的TC10合金封闭的铸造缺陷进行940～950℃、120～130 MPa、保温3～3.5 h条件下热等静压处理,然后对原缺陷部位进行了金相分析,发现弥合界面依然存在,为断续的黑色线状区域,因此对黑色区域做了扫描电镜-能谱(SEM-EDAX)分析,通过对比该区域与铸件本体化学成分,发现这些黑色区域并非杂质元素聚集的孔洞,而是合金元素不均匀的区域.分析认为,热等静压条件下铸造缺陷的弥合是一个蠕变、扩散连接的过程,当压力高于处理温度下的金属蠕变强度时,封闭的缺陷逐步弥合,时间越长弥合效果越好.
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