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.

[1]  L. Yin,et al.  Assessment of Elasticity, Plasticity and Resistance to Machining-induced Damage of Porous Pre-sintered Zirconia Using Nanoindentation Techniques , 2016 .

[2]  K. van Benthem,et al.  Temperature gradient and microstructure evolution in AC flash sintering of 3 mol% yttria-stabilized zirconia , 2017 .

[3]  K. Subramanian,et al.  Mechanisms of Material Removal in the Precision Production Grinding of Ceramics , 1997 .

[4]  I. Denry,et al.  Stabilized zirconia as a structural ceramic: an overview. , 2008, Dental materials : official publication of the Academy of Dental Materials.

[5]  Han Huang,et al.  Machining characteristics and surface integrity of yttria stabilized tetragonal zirconia in high speed deep grinding , 2003 .

[6]  Yinghui Ren,et al.  Influence of minimum quantity lubrication parameters on grind-hardening process , 2018 .

[7]  A. Kailer,et al.  Assessment of low-temperature degradation of Y-TZP ceramics based on Raman-spectroscopic analysis and hardness indentation , 2014 .

[8]  M. Rashad,et al.  Effect of thermal treatment on the crystal structure and morphology of zirconia nanopowders produced by three different routes , 2008 .

[9]  Stephen Malkin,et al.  Grinding Technology: Theory and Applications of Machining with Abrasives , 1989 .

[10]  Brij M. Bhushan,et al.  Tribology as an Enabler for Innovation in Surface Generation Processes , 2015 .

[11]  E. Brinksmeier,et al.  Friction, Cooling and Lubrication in Grinding , 1999 .

[12]  T. D. Howes,et al.  Material-removal mechanisms in grinding ceramics , 1994 .

[13]  I. Denry,et al.  State of the art of zirconia for dental applications. , 2008, Dental materials : official publication of the Academy of Dental Materials.

[14]  Andre D. L. Batako,et al.  Application of Minimum Quantity Lubrication in Grinding , 2012 .

[15]  M. Salehi,et al.  Grinding Force, Specific Energy and Material Removal Mechanism in Grinding of HVOF-Sprayed WC–Co–Cr Coating , 2014 .

[16]  R. Scattergood,et al.  Ductile-Regime Grinding: A New Technology for Machining Brittle Materials , 1991 .

[17]  J. Manappallil Basic Dental Materials , 2015 .

[18]  Stephen Malkin,et al.  Grinding Mechanisms for Ceramics , 1996 .

[19]  A. Evans,et al.  Transformation Toughening: An Overview , 1986 .

[20]  Stephen Malkin,et al.  Grinding Mechanisms and Energy Balance for Ceramics , 1999 .

[21]  L. Valandro,et al.  Mechanical behavior of a Y-TZP ceramic for monolithic restorations: effect of grinding and low-temperature aging. , 2016, Materials science & engineering. C, Materials for biological applications.

[22]  Zhijian Shen,et al.  Zirconia ceramics in metal-free implant dentistry , 2017 .

[23]  I. Inasaki,et al.  High-Efficiency Grinding of Advanced Ceramics , 1986 .

[24]  M. Sadeghi,et al.  An experimental investigation of the effects of workpiece and grinding parameters on minimum quantity lubrication—MQL grinding , 2009 .

[25]  Fredy Kuster,et al.  High performance grinding of zirconium oxide (ZrO2) using hybrid bond diamond tools , 2013 .

[26]  Knut Sørby,et al.  A Review on Minimum Quantity Lubrication for Machining Processes , 2015 .