However, in some small engines, the cylinder walls are plated with chromium, a very hard metal, to reduce wall wear and lengthen their life.
而对于一些小型发动机，气缸壁面镀铬，铬是一种硬度非常高的金属，可减少气缸壁的磨损并延长使用寿命。
2
Can cut very hard line energy type, for example, diagonal cutting pliers should consists of 0.8% carbon and certain components made of chromium and vanadium.