CHROMIUM PLATING POLLUTION SOURCE REDUCTION BY PLASMA SOURCE ION-IMPLANTATION

There is growing concern over the environmental and workers' health is sues due to the chemical baths and rinse water used in the hard chromi um plating process. In this regard the significant hardening response of chromium to nitrogen ion implantation can be environmentally benefi cial from the standpoint of decreasing the thickness and the frequency of application of chromium plating. In this paper the results of a st udy of nitrogen ion implantation of chrome-plated test flats using the non-line-of-sight plasma source ion implantation (PSII) process are d iscussed. Auger electron spectroscopy (AES) showed the implanted layer thickness to be about 2000 Angstrom. Electron spectroscopy for chemic al analysis (ESCA) indicated the formation of chromium nitride phase i n the implanted layer. The wear resistance improves after implantation owing to both surface hardening and a decrease in coefficient of fric tion. Corrosion resistance in saline solution improved moderately afte r PSII treatment.