Vlasovets' V. Improvement of service properties of steel and cast iron parts by spraying on a coating by means of arc electric metallisation

This research is aimed at studying the quality increase of worn-up heavyload and costly parts surface layer by application of coating with the help of arc electric metallisation. The goal of research is to increase service properties of tractor engines heavyload parts by application of coating and to give reasons for choosing a surface consistency that improves the grip and wear resistance. Techniques and appliances used: optic and electron microscopy, X-ray microanalysis, X-ray diffraction analysis and chemical analysis, microhardness evaluation, wear control, coercive force level evaluation. Grip hardness requirements are determined. Grounds for the choice of components are given, electroplating layer formation mechanism and kinetics are studied, which gives grounds for determining a coating and best parameters of its application at tractor engine crankpin build-up. Built-up parts operation tests have been carried out. A material is suggested, the main technological process factors and their corelati on are determined: they will provide the necessary level of heavyload parts working layer resistance and grip. It has been shown that grip hardness and wear resistance of the coating depend on the main technological parameters of the process. The necessary wear resistance is proved to be provided by the base formation (chrome and aluminium alloed ferrite) and excess phase disperse hardening, together with the pores which are operational lubrication spaces. The developments have been introduced at Sakhnovschina transport repair company: the total economic effect has been 368,700 hryvnias. The sphere of usage is engineering.