Han Ming Chow

In this paper, the effects of material removal rate and abrasive grain protrusion on the metal-based diamond grinding wheel were studied to find the optimal parameters for adding powder and wire discharge. In addition, this kind of electric discharge method to add powder on the metal-based diamond grinding wheel on line after dressing and truing will be applied on tungsten carbide to study the grinding material removal rate, grinding wheel wear, surface roughness, and surface micro-hardness.

This study aims to conduct experiments to explore metal based diamond wheel dressing and truing using developed wire electrical discharge (WEDM). The experimental outputs were analyzed to evaluate the effects of machining parameters on machining removal rate (MRR) and abrasive protrusion during dressing and truing caused by WEDM. During experiments, the wear and compensation issues could be overcome induced by the traditional EDM to improve the efficiency and precision as the WEDM was adopted. The experimental results showed as expected that the wire discharge grinding wheel dressing will lead the processing base not offset. In Taguchi experiment the maximum contribution was current and pulse time, large diameter grinding wheel to remove the highest rate of 11.78 mm3/min, while maximum protrusion amount only 33.12 μm, can reach the theoretical maximum protrusion amount.

This paper aims to establish an effective mathematical model with relation to electrical discharge machining (EDM) in gas based on response surface methodology (RSM). Moreover, the optimal combination levels of machining parameters for material removal rate (MRR) and surface roughness (SR) were also explored. The experimental tasks were implemented by a specific design of experimental method named central composite design (CCD) method based on RSM to develop quadratic regression mathematical model. The significant parameters and their interactions were examined by analysis of variance (ANOVA) to evaluate the importance on MRR and SR. The essential parameters of EDM in gas such as peak current (I_p), pulse duration (T_p), air pressure (G_P) and servo reference voltage (S_v) were chosen to investigate the effects on MRR and SR. From the analysis results, the optimal set of parameter setting levels were 12 A peak current (I_p), 750 μs pulse duration (T_p), 5 kg/cm2 gas pressure (G_P) and 34 V servo reference voltage (S_v), and the optimization of MRR and SR were 1.99 mm3 and 2.43μm as the machining parameters were set at the optimal levels.