The latter feature of a solder alloy is defined as the affinity and effectiveness of a molten metal to wet a substrate surface (such as Cu or Ni) under a given set of conditions.

• 焊料合金的润湿特性是指，在一定条件下，合金在融化状态下对基板界面（如：铜或镍）的润湿亲和力和润湿效率。