The Mechanism And Prevention Measures Of Grinding Cracks In The Parts Of Automotive Transmission

Automotive Transmission Parts (Material 20CrMnTi) after the heat treatment process is mainly within grinding. Grinding, due to the high grinding temperature in the grinding surface layer to form a larger thermal stress, and sometimes grinding cracks will appear. These grinding cracks will reduce the life of components, or cause parts scrapped. This article face grinding cracks on the causes and discuss measures to eliminate cracks.This paper will end the causes and grinding crack the measures to eliminate crack were discussed.The purpose of this study is based on the principle and grinding process and grinding grinding surface residual stress studied mathematics model of the relationship between stress of grinding, find out the factors effect. Then from stress, casting parts are fire method, heat-treatment method, grinding heat and grinding temperature control, parts of grinding conditions aspects of the grinding the causes of cracks are analyzed, and then from blank is fire, by grinding conditions heat-treatment, several aspects take measures to control grinding the fatigue.In the process of grinding cracks and grinding grinding force and grinding temperature related, so the fundamental measures to eliminate grinding crack is to reduce grinding temperature, reduce internal grinding force and eliminate parts.In the heat treatment is fire process, and conventional isothermal normalizing replacement parts are fire, get evenly balanced organization, for final processing provides good organization preparation, the final heat treatment deformation smaller, deformation regularity stronger. In the heat treatment carburizing aspects, control gear surface carbon concentration, control workpiece cooling speed, carburizing control austenitic grain degrees, reduce the number of residual austenite, eliminate or reduce stress, controlled source selection, cooling medium choice. In grinding machining process, and the grinding wheel, appropriate choice of appropriate cutting fluids, the rational choice of grinding parameters, the reasonable choice of grinding wheel dressing tools, grinding surface powerful shot peening treatment. Through adopts the above measures, and finally reach the purpose of eliminating parts grinding crack. Parts are fire, carburizing quench quality is the basis of grinding crack control; Resin-bonded grinding wheel to eliminate the use of face grinding crack plays a key role; Good cooling effect is to prevent parts the fundamental guarantee of grinding crack; For continuous process improvement, guarantee reasonable grinding machining parameters; The stand or fall of grinding wheel dressing quality is one of the important factors; To have a good grinding crack inspection method.Absorb others research results, with his work practice, to explore the method to eliminate parts grinding crack for control parts, provide a comprehensive grinding crack, for everybody reference solution.Eliminate grinding crack to enhance quality, reduce scrap loss, improve the competitiveness of their products have realistic meanings.