Yakunin Y. The influence of laser melting on a structure and properties of alloys.

The thesis is devoted to a problem of formation of a structure and hardening of alloys by laser melting. The correspondence of metastable structure forming process is analysed by laser handling and in case of other methods of quenching from a liquid state. It is shown that the basic reason of laser hardening is a formation of dispersed phase conglomerate structure. The mathematical model of melted by a laser radiation surface solidification of pure metals and alloys is offered. It is determined that laser amorphization is more difficult than amorphization by splat-method. The basic factors hampering the forming of a structure with a maximum metastability degree at laser melting are detected. This is a crystal growth from melting border without crystallisation centres forming and different degree of phase alloy melting.