Home | Contact Us
Surface treatments for steel


During the past 20 years, several processes have been introduced to obtain enhanced surface hardness of steels. Some of them have developed from case carburizing and nitriding, to obtain faster processing times with better environmental control and improved properties. Various salt bath processes have been used and now a wide range of new methods is available.


In the die casting industry surface treatments are applied to steels to improve the properties of nozzles ejector pins, cores and shot sleeves, to provide maximum resistance to erosion, pitting and soldering. Treatment of die cavities has received only limited acclaim, because the complex thermal patterns produced on large die components lead to stresses which are sufficiently high to break through the thin surface treated layers, leading to premature failure. Experience in drop forging has also indicated that surface treatments of their dies have not been particularly successful.


Thermochemical treatments are applied to die casting die components; the surface chemistry of the steel is modified by the introduction of nitrogen, carbon and sometimes other elements; the processes are of the main types listed below;

1.       Nitriding

2.       Nitrocarburzing such as Tufftride, sulfinuz and Suraulf

3.       Metallizing suzh as boronizing and the Toyota diffusion process

4.       Carburizing and carbonitriding

Post by:  Rita                email:sino9@cnmould.com