Study On Surface Integrity And Evaluation In Precision Machining

With the increasing demand of machining surface quality in the area of engineering application, surface integrity in precision machining has become one of the main directions for manufacturing science and technology. However, as for the new technology, there is a lack of systematic and thorough study in its study, especially in the evaluation and precision,which prevents the popularization and application to practical production.My work is based on metal cutting theory, and mainly studies the research of surface integrity in precision machining and its evaluation system. The dominated contribution are the following:1.By analyzing the formation of the machined surface in precision machining and the connotation for surface integrity, a new structural system of surface is set up,which is made up of surface quality, surface layer quality and edge quality. Based on this system, the conception, characteristics parameters, testing and control method are discussed in details.2.As the common phenomenon produced on edge of workpiece in cutting machining,burrs is one of the most important characteristics parameters.With the analysis of connotation for surface integrity and various surface integrity research status, the edge quality is proposed as the essential part of surface integrity. the conception, characteristics parameters, testing and active control method of burrs are discussed in details, which has enriched the connotation of surface integrity.3.According to the evaluating standards for surface integrity, the main characteristics parameters are put forward, of which the weigh value are determined by means of AHP.This method proves reasonable through consistency check. Based on the comprehensive evaluation which combines vague mathematics and expert consult, the result of surface integrity is showed in a qualitative and quantitative way.4.According to the experiment data, the precision models of residual stress and burrs on surface are built by using BP artificial neural network,which defines cutting parameters as input, and the value of residual stress and burrs characteristics as output. Finally,MATLAB is used to develop prediction system of the residual stress and burrs, which has a high accuracy.