Experimental study on the residual stress of the power spinning rod bushing with main technological parameters

Abstract

Abstract In the course of plastic forming, the residual stress of the power spinning connecting rod bushing will be produced. The residual stress will influence the dimensional precision and leads to bushing fatigue failure. In view of the residual stress size and distribution and the elimination of residual stress. In this paper, a single factor test was carried out for the research object with the power spinning rod bushing of tin bronze (QSn7-0.2). This paper puts forward the X-ray diffraction method combine with electrolytic polishing method to measure different levels of residual stress and carry on the analysis to the experimental result. The influences of the main parameters (thinning ratio, the first wheel of reduction, feed rate, heat treatment temperature and holding time) on the residual stress were obtained. The results show that: after the power spinning, the surface of the connecting rod bushing is the residual compressive stress, the inner layer is the residual tensile stress, the residual stress at both ends of the bushing is greater than the residual stress in the middle part of the work. In a certain range, the surface residual stress of the connecting rod liner increases with the increase of the thinning ratio, and decreases with the increase of the feed ratio then increases, and decreases with the increase of the first wheel thinning. In a certain range of temperature, the connecting rod bushing after the strong spinning is treated by heat treatment, the surface residual stress will decrease with the increase of temperature, and the longer the holding time, the more obvious the effect of removing residual stress