GH536合金管材“白圈”现象原因分析

Cause analysis of “white circle” phenomenon of GH536 alloy pipe

某钢铁研究所生产的Φ8.3 mm×2.3 mm的GH536合金管材在入厂复验时,发现管子外壁与基体组织有差异,表现在:管子外壁出现"白圈"现象。通过组织对比分析、不同固溶温度的热处理试验,结合管材的生产工艺流程,对"白圈"现象产生原因进行了分析。结果表明:管子"白圈"现象的产生是由于管坯在轧制过程中固溶温度低、保温时间短造成基体与外壁组织不均匀所致。

A batch of Φ8.3 mm × 2.3 mm GH536 alloy pipe was found that there was difference in the microstructure of pipe outer wall and matrix which shows ＂white circle＂phenomenon in the pipe outer wall.The heat treatment experiment at different solution temperatures was carried out,the microstructure was compared,and the reason of the＂white circle＂phenomenon was determined combining the manufacturing process of the pipe.The results show that the＂white circle＂phenomenon of the pipe is brought by the insufficient solution temperature and holding time of the pipe in the rolling process which causes inhomogeneous microstructure of the matrix and the outer wall.