基于Pareto前沿的单晶Si放电加工工艺参数优化

THE OPTIMIZATION OF THE PROCESS PARAMETERS IN THE COURSE OF THE ELECTRICAL DISCHARGE MACHINING OF THE MONOCRYSTALLINE SILICON WHICH IS BASED ON THE PARETO FRONTIER

针对电火花加工复杂、时变、多参数的特点,在单晶硅Si放电成型加工可行性的基础上,对材料去除率和表面粗糙度等工艺目标进行综合评价。采用中心组合设计实验综合考察峰值电流、脉冲宽度、脉冲间隔对P型单晶Si放电成型加工过程中材料去除率以及表面粗糙度的影响程度,通过响应曲面法分别获得材料去除率和表面粗糙度的二次响应模型,方差分析结果表明模型具有很好的拟合程度和适应性。以提高材料去除率和降低表面粗糙度为目标建立工艺参数优化模型,设计遗传算法对优化问题进行求解并得到Pareto最优解集。实验结果表明,料去除率的实验结果与优化预测结果平均相对误差为5.8%,表面粗糙度的实验结果与优化预测结果平均相对误差为5.3%。表明该算法能有效快速的实现P型单晶Si放电成型加工过程的工艺参数优化。

In view of the electrical discharge machining has the characteristics of complex, time-varying and multiparameter,based on the feasibility of the electrical discharge machining of the monocrystalline Silicon,this paper has a comprehensive evaluation of the material removal rate and the surface roughness and other technology goals. Using central composite design experiments,it comprehensively inspects the influence degree of the peak current、pulse width and pulse interval to the material removal rate and the surface roughness in the course of the electrical discharge machining of the P type monocrystalline silicon,it obtains the second-order response model of the material removal rate and surface roughness respectively through the Response Surface Methodology,the result of the variance analysis indicate that the model has good fitting degree and adaptability. Aiming at improving the material removal rate and reducing the surface roughness to establish the process parameters optimization model,it designs genetic algorithm for solving optimization problem and get the Pareto optimal solution set. The experimental results show that the average relative error of the experimental results of the material removal rate compare with the optimized forecast results is 5. 8%,the average relative error of the experimental results of the surface roughness compare with the optimized forecast results is 5. 3%,which is showing that this algorithm can rapidly and efficiently implement the optimization of the process parameters in the course of the electrical discharge machining of the P type monocrystalline silicon.