hardening process

例句：

1. 1. The steel undergoes a hardening process to become stronger.
   钢材经过硬化过程变得更强。
2. 2. During the hardening process, the material is subjected to high temperatures and pressures.
   在硬化过程中，材料受到高温和压力的作用。
3. 3.The hardening process is crucial for the durability of the product.
   硬化过程对于产品的使用寿命至关重要。