The spot inwall defect of aluminium alloy pipes during extrusion is one of the defects that only occur in the process of extrusion without lubrication.是什么意思_The spot inwall defect of aluminium alloy pipes during extrusion is one of the defects that only occur in the process of extrusion without lubrication.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句