Stainless steel butterfly valve corrosion solution
In the use of stainless steel butterfly valve, the phenomenon of rust always appeared. Through metallographic analysis, dyeing test, heat treatment test and SEM test, to find the key factors of material corrosion because carbide precipitates along the grain boundaries of materials formed in the chromium depleted zone, resulting in corrosion of stainless steel.
Solution to stainless steel butterfly valve corrosion
1 test methods
Sanitary valve reference: sampling for chemical analysis (to determine whether to meet the requirements of the standard), analysis process test and metallographic examination, heat treatment SEM.
2 test results and analysis
2.1 chemical composition analysis and standard components
2.2 metallographic analysis
The metallographic samples were cut from the valve corrosion phenomenon on the polished by grinding with a ferric chloride aqueous corrosion were analyzed gold emblem mirror, the microstructure is composed of austenite and another precipitates. In theory, austenitic stainless steel should be tre