任何特定用途的焊料类型和等级的选择取决于要连接的材料和应用方法。与锡含量较低的产品相比，锡含量较高的产品通常更容易润湿和粘合，且半熔融范围较窄。出于严格的经济原因，建议选择含锡量最少的焊料金属等级，以提供适用的流动性和粘合质量。

The choice of the type and grade of solder for any specific purpose depend on the materials to be joined and the method of applying. those with higher amounts of tin usually wet and bond more readily and have a narrower semi- molten range than lower amounts of tin. For strictly economic reasons, it is recommended that the grade of solder metal be selected that contains least amount of tin required to give suitable flowing and adhesive qualities for application.