Optimization and analysis of machining parameters by EDM on the surface roughness of AISI P20 steel

This experimental research aims to analyze the influence of electrical parameters of electrical discharge machining (EDM) on the average roughness (R-a) of AISI P20 steel, which is widely used in the mold industry for thermoplastic injection. It is also proposed in this study the optimization of these parameters to obtain the desired surface roughness of the material. The planning and statistical results were obtained through the experiment design methodology (DOE). Statistica software was used to create graphs and tables based on the response surface methodology (RSM). The analysis of the results showed that the duration of the discharge pulse (T-on) and the intensity of the electric current are the parameters with the greatest effect on surface roughness. Based on other studies on EDM, the statistical analysis presented results in conformity with regard to the influence of factors. The optimization graph consistently indicated the adequate levels of adjustment of the parameters to obtain the desired response. It can be verified in this research in specific, what are the significant electrical parameters for the average surface roughness, being its knowledge and control, fundamental for the optimization of the process. Statistical techniques were presented as very useful tools for mastering industrial technology, especially in cases where there is a need to adjust many factors, generating predictability, economy, agility and reliability to the process.