Rather than adding other metals, they developed a complex mechanical process involving repeated heating and very severe mechanical deformation, known as tempforming.

他们不添加其他金属，而是研发了一个复杂的机械程序，涉及反复加热以及重度机械变形，这个程序被称为热成型。

This rugged material got even stronger in the 19th century, when Levi Strauss and Jacob Davis added metal rivets to reinforce stress points.

这个耐用的材质在十九世纪又更强化了，因为李维‧史特劳斯和雅各布‧戴维斯在布上加了金属铆钉来稳固受力点。