液氧容器内球体裂纹分析

用光学显微镜、电子探针和扫描电对液氧容器内球体裂纹进行了细致的检查分析。结果表明，该零件开裂是由于焊缝热影响区镀铜层未打磨干净，有些地区打磨面积 ，未超越氩弧焊接时引起民金属铜熔化的区域，在焊接应力作用下，熔融铜沿晶界渗入母体金属引起铜脆。

Crack Analysis of Inside Sphere of Liquid Oxygen Vessel

The crack of inside sphere of liquid oxygen ressel has been analyzed by using OM,EPMA and SEM. It has found that the layer of cuprum plating near weld bead and heat af- fected zone was not removed complettly by grinding and/ or the area was removed too small to melt layer of cuprum.the cuprum melts osmose along the capillary in matrix grain boundaries. As a resuld,Once the welding stress is acted upon,the cuprum embritteement will be produced.