Laser Surface Melting Of Iron-Base Alloys

Abstract

Laser surface melting of cast iron is, apart from laser cutting and welding, a major area of industrial interest. There are a number of technical reasons which justify the use of lasers in this area. First of all, cast iron is a cheap starting material with a lower melting point compared to iron. On the other hand, casting is still the cheapest way of metal forming. For this reason it is suitable for the production of automobile car parts. Such parts are manufactured in large numbers, and therefore the advantage of lasers is the high degree of possible automation. On the other hand, the high flexibility of laser manufacturing allows small variations in components of the various models in one type of car. The metallurgical reason why laser surface melting of cast iron is an interesting process is the almost ideal combination of strength and ductility of the core and the wear resistance of the melted surface. Favorable compared to classical methods is the fact that also relatively thin surface layers can be produced (1). In the following the metallurgical and technical aspects of laser surface melting of cast iron are discussed.