| Because of many advantages of magnesium alloy, such as lightweight, high carrying capacity, small modulus of elasticity, high stiffness, high aseismatic capability, shield against electromagnetic interference, recyclable utilization and so on , it is widely used in vehicles, motorcycles, electronics, aviation, aerospace , military and other fields. However, the corrosion-resistant capacity of magnesium alloy is the biggest obstacle to application of this kind of alloy. Improving the surface quality before plating and coating can greatly enhance the bonding strength between the coating material and rough material and enhance corrosion-resistant capacity. Because the magnesium plating and coating companies lack a convenient way to be used in the mechanical processing before plating and coating, so it is became a problem to be verified that whether belt grinding advantage can be used in this processing to improve the quality of products.Aiming to solve the problem listed above, this paper completed basic research of magnesium alloy belt grinding taking the typical casting magnesium alloy materials, AZ91D, for the study,.(1) This paper summed up the present status quo at home and abroad, analyzed the grinding capability of the typical die-casting magnesium alloy material, and completed the improvement of magnesium alloy belt grinding experimental device. Magnesium alloy plating for pre-processing machinery processing the request by the Belt grinding performance evaluation of the main targets is put forward aiming at satisfying the requirements of mechanical processing before plating and coating.(2) This paper studied on the influence law of the grain size, belt line speed, feed rate, and other factors on the surface roughness, and built the model by means of multiple linear regression analysis and BP neural network to forecast the processed roughness.(3) This paper creatively put forward a new way, using the blinding area, to evaluate the blinding degree; studied the influence law of the abrasive belt blinding by means of experiment; built the model of the influence law of the abrasive belt blinding using the BP neural network and MATLAB for the forecast of the abrasive belt blinding.This paper got some conclusions: (1) It is feasible to apply the Belt Grinding technology on the magnesium alloy grinding(2) Under certain grinding conditions, the biggest factor impact the surface roughness is the grain size, next are the grinding pressure, belt linear velocity, the work piece feed rate and the hardness of the conduct wheel.(3) 3,A multiple linear regression model between the surface roughness and the grinding input parameters was built. It is certificated that the biggest error between regression model solver and the experimental value is only 8.0% meeting the requirements of precision.(4) It is simple and accurate to adopt the new way that using blinding area to evaluate the belt blinding degree. During the grinding magnesium alloy process, the biggest impact factor is the grinding pressure, to be followed by the belt liner velocity, grain size and rate between trough and tooth of contact wheel. When the blinding area close to the 70%, it is better to change this belt because in this situation, the belt lost the capability of removing the surface metal.(5) Two models were built by means of BP neural network and MATLAB, one is the influence model of surface roughness, and the other is concerning the belt blinding situation. It was proved that these two models of prediction accuracy, respectively 6.4% and 4.17%. And these two models can be used to guide the practice.
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