Study on grinding of pre-sintered zirconia using diamond wheel

ABSTRACT

Zirconia-based ceramics are the most preferred materials used in implants due to their excellent mechanical properties compared with other alternatives. These materials available in the pre-sintered form are appropriate to grind due to their soft nature. However, it is challenging to achieve a required surface finish in grinding these ceramic materials owing to chipping, which limits its usage in industries. In this work, the pre-sintered yttria stabilized tetragonal zirconia (Y-TZP) component was ground using a resin-bonded diamond-grinding wheel under different cooling environments. The components ground under the minimum quantity lubrication conditions exhibited a reduced grinding force with better surface finish compared to wet (flood coolant) and dry conditions. The resultant specific energy was reduced with the increase in maximum chip thickness for different cooling conditions. The critical depth of cut estimated from the pre-sintered zirconia was witnessed to be higher, which indicated that the initiation of ductile to brittle transition occurred at a deeper depth of cut. The material removal mechanism observed in the pre-sintered zirconia was dominated by brittle fracture. This was evident from the obtained chips and ground surface morphology.

KEYWORDS:

• Chips
• damages
• forces
• grinding
• morphology
• surface integrity
• zirconia