Analysis of abrasive belt wear effect on residual stress distribution in robotic belt grinding of GH4169

Belt grinding is commonly applied for precision manufacturing of difficult-to-machine materials like GH4169, owing to its satisfactory elastic grinding properties, high efficiency, and strong adaptability. Abrasive belt wear is a common occurrence during the grinding process; however, its mechanism and effect on machining quality, particularly its influence on residual stress (RS), remain unclear. In order to compensate for these shortcomings, by means of experimentation, this paper studies how the RS distribution of GH4169 plate is affected by abrasive belt wear during robotic belt grinding, and the influence mechanism is analyzed from the perspectives of grinding force and heat. Firstly, the whole life cycle of the abrasive belt is determined through a wear test, then a novel evaluating index based on relative material removal rate is proposed to quantitatively characterize the wear conditions of belt. Secondly, according to the new division criteria, abrasive belts at various wear stages are created, and then, comparative grinding experiments of the GH4169 plate are carried out. Finally, based on the experimentally measured data, this paper fully analyzes and discusses the surface and subsurface RS distribution differences of grinding traces. The experimental findings suggest that the effect of abrasive belt wear on the surface RS distribution is notable in the grinding direction, but not in the vertical direction of the grinding traces. Additionally, as the belt conditions deteriorate, the overall grinding force ratio decreases while the accumulation of grinding heat increases, which leads to the generation of surface residual tensile stress (RTS) in the grinding direction. Furthermore, as a result of the uneven heat diffusion, the surface RS along the vertical direction of the grinding traces is distributed in an approximately symmetrical manner, with higher RS values in the center and lower values on the sides. As for the subsurface RS distribution, on the whole, with the progression of belt wear, the values of the subsurface residual compressive stress (RCS) layer decrease.