常见螺丝材质:a. Low Carbon Steel ：低碳钢b. SS-304: Stainless Steel 304c. SS-302: Stainless Steel 302: 结构韧性较好d. Aluminum 5052: 铝合金 5052d. Brass: 黄铜e. Bronze: 青铜f. UNS C11000 Copper: 锑铜Finish Code: 外观处理规格Head Co