Research On The Wear Mechanism And Regrinding Process Of Hard Alloy Disc Cutter

The transformation and upgrading of metal products processing industry requires improving metal products precision and material utilization, slitting the wide sheet metal to be the required width of the strip is the basis of precision metal products, therefore it puts forward new and higher requirements for sheet metal precision slitting processing technology. This paper is composed of the following parts researching on hard alloy disc cutter and electromagnetic steel sheet slitting process:(1) the study of disc cutter blade wear condition and the wear mechanism in order to improve the quality of slitting sheet;(2) the research of the regrinding process of disc cutter in order to work out the best grinding quantity and grinding quality standard;(3) the analysis of the blade formation mechanism and side oxidation of disc cutter.This paper generally describes the present situation of domestic and foreign researches about the slitting technology, WC-Co hard alloy material properties, tool wear and grinding. The contact relationship between the disc cutter and the sheet metal, the loading process, the wear of disc cutter in slitting process and influencing parameters in regrinding process were analyzed.The disc slitting experiment for the electromagnetic steel sheet was conducted to investigate the wear process of hard alloy disc cutter and its effect on the slitting burr of sheet in the disc slitting process, and the wear of the disc cutter and the burr of electromagnetic steel sheet were examined by the optical microscopy and surface profiler. The results show that the wear of the disc cutter increases with the increase of the slitting length, the radius of the cutting edge and the height of the side wear zone also increase. Disc cutter wear process can be divided into the early wea^ stable wear and sharp wear, the blade needs regrinding when the sheet burr is excessive. The wear of disc cutter directly affects the slitting burr height of electromagnetic steel sheet. When the slitting length reaches 5000m, the height of the side wear zone reaches 26am, the edge radius reaches 37u,m, and the burr’s height is 15μm.The worn disc cutter were regrinded on the universal grinding machine to investigate the grinding quality of the disc cutter in order to get the relationship between the wear process and the reginding process of the disc cutter. The results show that the cutting edge radius of the disc cutter and the height of the side wear zone reduce with the increase of the grinding quantity, but the radius of the cutting edge of the blade is stable after reaching 15μm, and the height of the side wear zone always remain around 5μm, the blade quality cannot continue to improve. Residual wear zone of disc cutter side still exists after grinding in fine grain of grinding wheel and small feeding.Simulation grinding experiment was conducted on surface grinder in order to study the residual wear zone of disc cutter side and the formation mechanism of disc cutter blade in grinding process. The results show that, the existence of the residual wear zone has nothing to do with the disc cutter cylinder surface roughness, while it was caused by oxidation wear on the disc cutter side, and the reason of side oxidation is that humidity of the environment was excessive at room temperature. With the increase of service life of disc cutter, side oxidation degree increased, and surface density and surface hardness decreased, then residual wear zone of disc cutter is more easily to occur.