noun · acetal resin, also known as polyoxymethylene (POM) or by the brand name Delrin

这种精密机械齿轮是由塑钢制成的。

noun · unplasticized polyvinyl chloride or rigid PVC, frequently used in construction for window frames

塑钢门窗因其耐腐蚀和保温性能而受到欢迎。