Lawv feem ntau yog tsim los siv cov hmoov hlau metallurgy, qhov twg cov hmoov hlau yog nias thiab sintered ntawm qhov kub thiab txias los tsim ib qho kev sib tshuam, cov qauv ntxeem tau nrog lub zog tshwj xeeb.

Lawv feem ntau yog tsim los siv cov hmoov hlau metallurgy, qhov twg cov hmoov hlau yog nias thiab sintered ntawm qhov kub thiab txias los tsim ib qho kev sib tshuam, cov qauv ntxeem tau nrog lub zog tshwj xeeb.
