Chip formation

Engineering

Grinding

Metallurgy

Materials science

Ceramic

Lubrication

Tool wear

Mechanical engineering

Cylinder

Composite material

Machining

Brittleness

Chip

Cubic zirconia

Coefficient of friction

Friction coefficient

Electrical engineering

The International Journal of Advanced Manufacturing Technology

The removal of material in the ductile regime while improving machining efficiency is currently the technical bottleneck in grinding zirconia ceramics. Prediction models of minimum chip thickness (hmin) and ductile–brittle transition chip thickness (hd–b) were developed according to grinding mechanism. Results showed that both hmin and hd–b decreased with increasing friction coefficient. Grinding experiments were carried out using the maximum undeformed chip thickness as the input parameter. Experimental results showed that the hmin value in dry grinding is 0.24 μm. Meanwhile, the hmin values under minimum quantity lubrication (MQL) and nanoparticle jet MQL (0.4, 0.8, 1.2, 1.6, and 2 vol.%) are 0.27, 0.34, 0.49, 0.65, 0.76, and 0.91 μm, respectively. Furthermore, the hd–b value in dry grinding is 0.8 μm, and the hd–b values under lubrication condition that corresponds to hmin are 1.79, 1.98, 2.15, 2.27, 2.39, and 2.59 μm, respectively. The experimental results show the same trend as that of the prediction model. The theoretical calculation is basically consistent with the measured values, with model errors of 7.9% and 6.3%, thereby verifying the accuracy of the chip thickness models.

Effect of friction coefficient on chip thickness models in ductile-regime grinding of zirconia ceramics