Experimental Study And Analysis Of Single Plane Grind-hardening Process

The grind-hardening is a composite machining technology which quenches the steel work-piece surface directly by the grinding heat generated during the process.This technology not only integrates the grinding manufacturing and surface quenching heat treatment,but also reduces the emission of hazardous substances such as the waste water and rubbish.It has advantages of the economical efficiency,society and environmental protection,whose engineering application prospect is very wide.Based on the single plane grinding experiment and the residual stress test in the grind-hardening process,the temperature field and thermal stress field model of the grind-hardening zone were established through ANSYS 16.0.The formation and change rule of the temperature and thermal stress in the hardened layer of work-piece surface were revealed under the loading of triangle moving heat source model,which provides the theoretical and experimental basis for improving the quality of grind-hardening technology.The primary contents and new trails are as below:(1)In view of the single plane grind-hardening experiment,the grinding temperature and grinding force in the grinding process were measured with the infrared thermal imager and the three-way piezoelectric dynamometer sensor.The influence and action law of grinding parameters including the grinding speed,the grinding depth and the feed speed on the distribution of temperature field and the grinding force were systematically analyzed and revealed.(2)By measuring instruments such as optical digital microscope and digital micro-hardness tester,the change law of the micro-hardness and the depth of the grind-hardening layer were studied under the experimental condition with different grinding parameters.The relationship between properties of the grind-hardening layer and grinding parameters were deeply revealed;Combined the corrosion stripping layer with X-ray diffraction method,the distribution of residual stresses on the surface of the hardened layer were measured.Meanwhile,the relationship between the residual stress and the hardened layer depth was also discussed.(3)The heat source model for the plane grind-hardening process was establishedbased on the triangle moving heat source theory.With the heat flux distribution of temperature field in the grind-hardening area,the formation and change of temperature field and thermal stress field of the single plane grind-hardening were simulated under the action of the triangle heat source model by using the finite element software ANSYS.Comparing simulation results of the grind-hardening layer depth with the experimental data,the validity and reliability of the model were verified,which provides the basis for actively controlling the grind-hardening process and improving the quality of machining.This study is an important part of National Natural Science Foundation of China,which is of great significance to further reveal the formation mechanism of the grind-hardening,to develop the grind-hardening process theory and to promote the application of the grind-hardening technology.