Nrog loj txiav chamber thiab ua haujlwm yooj yim rau cov neeg siv, lub tshuab txiav yog ib qho ntawm metallographic kuaj tsim nyog cov qauv npaj khoom siv rau cov tsev kawm qib siab, tsev kawm qib siab, Hoobkas & cov lag luam.
