四通电磁换向阀毛细管开裂失效分析

Failure analysis of capillary cracking of four-way solenoid reversing valve

某型四通电磁换向阀毛细管在火焰钎焊后,焊缝附近发生开裂现象。为了解开裂原因,从源头控制产品质量,对母材进行金相、平均晶粒度尺寸、扫描电镜和X射线能谱测试。结果表明,焊接晶粒尺寸及晶粒大小不均匀对焊接开裂影响较大。

After the flame brazing on the capillary of the four-way solenoid reversing valve,cracking occurred near the weld seam.In order to understand the causes of cracking and control the product quality from the source,the metallographic,average grain size,SEM and EDS tests are conducted on the base material.The results show that the welding grain size and grain unevenness have a greater impact on the welding cracking.