Research On Polishing Mechanism&Process Parameters Decision-making For Cemented Carbide Blades In CMP

F For its excellent material properties, cemented carbide tools always play an importantrole in the cutting tool industry, in which cemented carbide blades occupy the largest scope ofapplication. Now grinding is still the main precision processing method for cemented carbideblades. However, heat deformation, grinding burn and microcracks generated by grindinggreatly reduce the blade performance and life. As the demand of processing precision of partsis increasing, mechanical damage can be avoided and the flatness of blade surface can beincreased by CMP, which has less heat-affected. Therefore CMP is one of the most importantprecision and ultra-precision machining methods without doubt. There is urgent need for deepand systematic research on cemented carbide blades CMP. To explore the polishingmechanism of CMP and establish scientific processes parameters decision-making, theresearch focuses on the polishing mechanism and process parameters decision-making ofcemented carbide blades CMP. The polishing mechanism is theoretically analyzed. Based onthe combination of orthogonal test, Taguchi method, and BP neural network, the processparameters for cemented carbide blades CMP is optimized and the polishing qualitypredicting models are built. Finally based on intelligent decision technology, the processparameters intellectual decision supporting system for CMP is developed. The main works inthe paper can be concluded as the following:(1) Theoretical analysis of polishing mechanism. By describing dynamic process ofcemented carbide blades CMP, the combination of chemical and mechanical influences isanalyzed. The contact model between polishing pad and workpiece and the contact modelbetween workpiece and abrasive are established. The material removal mechanism of singleabrasive and chemical mechanism are analyzed.(2) Optimization of process parameters for cemented carbide blades CMP. A multi-stepplanning process is proposed. Material removal rate and surface roughness are regarded asevaluation of polishing quality. YG8blade product as the example, based on orthogonal testand Taguchi method, the combination of the best process parameters is obtained byoptimizing process parameters.(3) The polishing quality predicting models are built. Based on the above step2and BPneural network, the polishing quality predicting models for cemented carbide blades CMP arebuilt to predict MRR and Ra affecting by process parameters.(4) A database of polishing process parameters is established. Based on the above step1and2, the process intellectual decision-making model is proposed and the CMP process parameters database is established by using Access.(5) The intelligent decision system for CMP process is developed. Based on the abovestep4and the intelligent decision technology, by utilizing hybrid reasoning method, theintelligent decision system for CMP process is developed, which can successfully achieveprocess decision-making, process parameters decision-making and polishing qualityprediction. Finally the developed system is tested.In conclusion, the research laid a theoretical foundation for the process theory of thecemented carbide blades CMP and scientific decision-making of process parameters, whichcan further accelerate the intelligent processing level of precision and ultra-precisionmachining for cemented carbide blade.