Influence of the Applying Mode of the Antifriction Coating by Ultrasonic Treatment on the Roughness of the Treated Surface

Abstract

The article presents an experimental study of the effect of the ultrasonic diamond smoothing mode on the surface roughness of the roller bearing roller end face in the presence of graphite nanopowder on the treated surface. In the presence of graphite nanopowder on the surface, the diamond smoothing process is accompanied by the formation of a solid antifriction coating on the treated surface, which can affect the formation of the microrelief of the treated surface. The design of an ultrasonic installation is described for diamond smoothing of the rollers end surface with the possibility of simultaneous application of a solid antifriction coating to this surface. The installation is assembled on the basis of a 16K20 screw-cutting machine. It consists of a device for installing rollers in the chuck of the lathe and an ultrasonic transducer mounted on the caliper of the machine. A diamond tip was used as a working tool in this device which was attached to the end of the oscillation concentrator of the ultrasonic transducer. Axle box bearing rollers of 36-42726E2M series (GOST 18855-94) were used as experimental samples. The subject of research was regression dependences of the influence of ultrasonic processing mode on the treated surface roughness. Full factorial experiment method was used to conduct the research. The tool tip rounding radius, tool transverse feed, specimen rotation speed, and tool pressure force on the machined surface of the specimen were used as varying factors. The power-law dependence of treatment indices on the adopted varying factors was taken as a mathematical model. It is shown that the greatest influence on the surface roughness is exerted by the tool transverse feed and the diamond tip rounding radius.

Keywords

• surface roughness
• ultrasonic treatment
• diamond smoothing
• treatment mode
• diamond tip
• roller