Saychuk O. Increase the durability of articles by the combined treatments and alloying with the use of laser ray

The thesis for degree (candidate of technical sciences) in specialty of 05.02.01 - Material science. - The Kharkiv National Motor and Highway University, Kharkiv, 2010. The thesis deals with development of technology that would allow for improving the parts longevity through renovation of a working surface. The purpose of the developments is to upgrade the technological processes and to optimize the parameters of comprehensive methods of parts renovation as well as to work out new solutions related to surface modification. The comprehensive methods and optimal parameters used for renovation of the parts are based on combination of treatments of a different type through applying coatings that are subjected to hardening. The developed combined technology provides increase in hardness of a working layer by factor of 1.4, while roughness is decreased by 30 to 35%. The method of surface modification using the laser beam has been offered. The experimental studies proved the selected optimal parameters of surface modification that were obtained through theoretical computations. Based on the obtained research results the recommendations were given with regard to the surface FeCr+C modification and special technological approaches that provide increase in service durability on the average of 1.33 times. Key words: renovation of a working surface, complex methods, laser treatment, structure, components distribution, properties and surface, alloying.