1. Dab tsi yog casting Cov kua hlau yog poured rau hauv pwm kab noj hniav nrog ib tug zoo haum rau ib feem, thiab tom qab nws solidifies, ib feem khoom nrog ib tug tej yam zoo li, loj thiab nto zoo, uas yog hu ua casting. Peb lub ntsiab tseem ceeb: alloy, qauv, pouring thiab solidification. Cov...
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