钛合金裂纹产生原因及改进工艺
吴晓明,王 玉,郭 蓓,高 斌,高怀胜,杨欢庆

(西安航天发动机有限公司,陕西 西安 710100)

钛合金; 裂纹控制; 仿真模拟; 铸造工艺优化; 气体保护

The research on defect analysis of titanium alloy and improved process
WU Xiaoming, WANG Yu, GUO Bei, GAO Bin, GAO Huaisheng, YANG Huanqing

(Xi'an Space Engine Company Limited, Xi'an 710100, China)

titanium alloy; crack control; simulation; casting process improvement; gas protection

备注

针对某型号发动机壳体组件水力试验后进口段荧光线性缺陷问题,通过对缺陷进行宏观观察、金相组织检查、断口分析、材料成分分析和硬度检查,确定了缺陷类型产生原因。运用Procast铸造仿真模拟软件开展了针对性的改进工艺研究。结果 表明:进口段荧光线性缺陷为裂纹,呈典型的准解理断裂特征。表层脆而硬的富氧层是导致壳体开裂的诱因,其形成与补焊有关。基于仿真模拟的改进工艺成功将缺陷转移至冒口,减少铸件内部缺陷数量,降低补焊量; 使用氩气保护箱改善气体保护效果,提高补焊质量。改进措施实施后,铸件、零件以及组件的荧光检查均一次合格,并且顺利通过地面试车考核,解决荧光线性缺陷问题,消除了薄弱环节,提高了发动机的可靠性。

The problem of fluorescence linear defect after hydraulic test of a certain type of engine shell component was discussed, the defect type and generating reasons were researched by macro-observation, metallographic technology, crack analysis composition analysis and harness checking.Procast casting simulation software was used to improve the process.The results show that defect type is crack, showing the quasi cleavage crack.The surface oxygen rich layer caused the crack of the shell.The crack formation is related to repair welding combined with the production process.The improved process transferred the defects to the riser by simulation, reduced the number of defects and repair welding.The Argon gas shield was used to improve the efficiency of shielding and quality of repair welding.By using above measures, the fluoroscopy results of casting, component and groupware were qualified.In addition, the product passes the ground test.The problem of fluorescence defects is solved, the weak link is eliminated, and the reliability of the engine is improved.