Nyob rau hauv lub zog cia chaw vuam tshuab, kom ntseeg tau qhov zoo thiab kev ncaj ncees ntawm cov pob qij txha yog qhov tseem ceeb tshaj plaws. Txhawm rau ua tiav qhov no, ntau txoj hauv kev tshuaj xyuas yog ua haujlwm los ntsuas cov pob qij txha rau qhov tsis xws luag, xws li fusion tsis txaus, tawg, lossis porosity. Kab lus no tshawb txog ntau yam tech...
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