以剖分试样真空处理法研究了钢内部裂纹的高温愈合行为，将含预置内部裂纹的 ２０ＭｎＭｏ钢及 ２０号和 ４５号钢试样剖分后封入真空度达 １３３×１０－４ Ｐａ的石英管高温处理 ４５ｍｉｎ．发现试样剖分面上的裂纹均出现愈合迹象，愈合区内呈现铁素体组织形态，与采用整体试样处理法所观察到的高温处理后内部裂纹愈合形态基本一致，这表明以剖分试样真空处理法研究钢内部裂纹愈合行为的可行性，压合效应要比单纯高温处理时的其它机制对钢中裂纹愈合的作用大 The high-temperature healing behavior of internal cracks in steel was investigated by the method of vacuum treatment. The specimens with 20MnMo steel and 20 and 45 steel pre-internal cracks were sectioned and sealed in a vacuum degree of 133 × 10-4 Pa High temperature quartz tube 45min. It was found that the cracks on the split surface of the sample all showed signs of healing. The shape of the ferrite in the healing area was basically the same as that observed after the high-temperature treatment with the whole specimen treatment method. The feasibility of sample vacuum treatment to study the healing behavior of cracks in steel is better than that of other mechanisms at high temperature