ABSTRACT
Important surface treatment methods include coatings deposited by both chemical and physical methods. However, new techniques of producing modification of surfaces have assumed great importance. Surface coating can be described as a covering applied to the outer face of an object, whereas surface modification is best described as changing the nature of the outer surface. Probably the simplest example of chemical deposition is the ability of copper to plate out onto iron which is immersed in a solution of a copper salt. The process of electrodeposition is essentially the cathodic site of the same electrochemical reaction which causes corrosion on the anodic site. The process of ion implantation provides a completely new method for improving the durability of material surfaces. Laser processing utilizes a laser to produce a source of energy which, when in contact with materials, can produce a large amount of heat in a very small volume of material.
