常见例句双语例句When an aluminum rivet is upset against a softer material, a washer must be used under the upset head to prevent eruption of the softer material.当一个铝铆钉的镦头形成在较软的材料一边时，必需在铆钉镦头下使用垫片以防止较软材料胀裂。 返回 upset rivet