Research And Development Of Cutting Database System For SiCp/Al Composites

Silicon carbide particle reinforced aluminum matrix composites(SiCp/Al)is a kind of composite material,advantages of which are improved strength,stiffness,modulus of elasticity and low thermal expansion coefficient and so on.SiCp/Al has been widely used in the field of various industries.But the harder and brittler SiC particle makes tool wear serious,even collapse edge in the process of machining of SiCp/Al.That makes machining efficiency and quality poor.Reasonable selection of cutting parameters can reduce tool wear effectively,get longer tool life,and improve the machining quality.Because of the lack of relevant theoretical guidance and inadequacy of relevant processing experience,the selection of cutting parameters is very difficult in the actual machining process.It is of great significance for application of SiCp/Al composite materials to establish cutting database system of SiCp/Al composite materials to provide reasonable cutting parameters.The main contents of this thesis include the following.Firstly,a technology plan for the cutting database system development was drawn up.According to the cutting process of SiCp/Al composites,the demand analysis was carried on.Based on a summary of demand analysis,database was established in the physical media.The general structure of the cutting database system was designed with modular development train of thought,.Then,the optimization method of SiCp/Al composite materials has been studied.The functions,which make productivity maximum and production cost minimum,have been set up.According to the constraint conditions,constraint functions have been established.Then,the cutting parameters were optimized by genetic algorithm.The process parameters such as tool life,cutting force and surface roughness have important influence on the cutting parameters selection.So,established the tool life,cutting force and surface roughness model by the regression analysis method in this thesis.Finally,the reliability of the optimization method and the modeling method were proved by the experiment.Subsequently,the intelligent reasoning methods of cutting parameters were studied.In this thesis,the Case Based Reasoning has been applied to reason cutting parameters.In the process of reasoning,the object-oriented case representation method has been used to describe the cases.Nearest neighbor method is used to achieve similar case,and the similarity theory is used to rewrite cases.The reliability of rewriting is proved by the experiment.Finally,the cutting database system for SiCp/Al composites,which is based on B/S mode,was established by codes.The main function modules include data query,recommendation of cutting parameters,optimization of cutting parameters,modeling and forecasting of process parameters,intelligent reasoning of cutting parameters and data maintenance,etc.