 |
| |||
| 表面硬化法 (In the simplest method of case-hardening the steel articles are packed in boxes containing charcoal and other substances; they are then heated gradually to about 925°C, and maintained at that temperature for several hours. 最简单的表面硬化法是将钢件放人盛有木炭和其他材料的箱子中，然后逐渐加热到大约 925°C， 并在此温度下保持几小时。) | |||