| 摘要 |
Ferrous articles are nitrided, carburized or sulphurized by immersing them in a bed of carbon black particles fluidized by a stream of air, there being introduced into the bed a treatment gas which is a compound of hydrogen with the element to be diffused into the surface. The treatment is carried out at 300 DEG -900 DEG C., particular ranges specified being 500 DEG -650 DEG C. when using ammonia, 600 DEG -900 DEG C. when using propane, and 300 DEG -600 DEG C. when using hydrogen sulphide. |
