Laser-Assisted Machining of Magnesia-Partially-Stabilized Zirconia

Laser-assisted machining (LAM) of magnesia-partially-stabilized zirconia (PSZ) is investigated to determine the effect of heating on machinability, as determined by tool wear, cutting energy, surface integrity, and material removal mechanisms. It is found that PSZ can be successfully machined with a polycrystalline cubic boron nitride tool and that tool life increases with material removal temperature up to a maximum of 121 minutes. The benefit of laser-assistance in material removal is also demonstrated by the 2.5 fold decrease in the specific cutting energy with increased temperature. It is shown surface roughness varies significantly with tool wear with little dependence on cutting temperature unlike in LAM of other ceramics. Evidence of mixed brittle and ductile material removal mechanisms is presented, and the optimum condition within the test matrix is established.

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Laser-Assisted Machining of a Fiber Reinforced Metal Matrix Composite

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4002548 ◽

2010 ◽

Vol 132 (6) ◽

Cited By ~ 27

Author(s):

Chinmaya R. Dandekar ◽

Yung C. Shin

Keyword(s):

Tool Wear ◽

Metal Matrix ◽

Material Removal ◽

Volume Fraction ◽

Cutting Speed ◽

Subsurface Damage ◽

Matrix Composites ◽

Specific Cutting Energy ◽

Laser Assisted Machining ◽

Cutting Energy

Metal matrix composites, due to their excellent properties of high specific strength, fracture resistance, and corrosion resistance, are highly sought after over their nonferrous alloys, but these materials also present difficulty in machining. Excessive tool wear and high tooling costs of diamond tools make the cost associated with machining of these composites very high. This paper is concerned with the machining of high volume fraction long-fiber metal matrix composites (MMCs), which has seldom been studied. The composite material considered for this study is an Al–2% Cu aluminum matrix composite reinforced with 62% by volume fraction alumina fibers (Al–2% Cu/Al2O3). Laser-assisted machining (LAM) is utilized to improve the tool life and the material removal rate while minimizing the subsurface damage. The effectiveness of the laser-assisted machining process is studied by measuring the cutting forces, specific cutting energy, surface roughness, subsurface damage, and tool wear under various material removal temperatures. A multiphase finite element model is developed in ABAQUS/STANDARD to assist in the selection of cutting parameters such as tool rake angle, cutting speed, and material removal temperature. The multiphase model is also successful in predicting the damage depth on machining. The optimum material removal temperature is established as 300°C at a cutting speed of 30 m/min. LAM provides a 65% reduction in the surface roughness, specific cutting energy, tool wear rate, and minimum subsurface damage over conventional machining using the same cutting conditions.

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Surface/Subsurface Damage of Yttria Partially Stabilized Zirconia in Grinding Using Monolayer Brazed Diamond Wheel

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.431-432.326 ◽

2010 ◽

Vol 431-432 ◽

pp. 326-329

Author(s):

Shu Sheng Li ◽

Jiu Hua Xu ◽

Yu Can Fu ◽

Hong Hua Su

Keyword(s):

Material Removal ◽

Chip Thickness ◽

Diamond Wheel ◽

Critical Value ◽

Subsurface Damage ◽

Ductile Material ◽

Grinding Wheel ◽

Stabilized Zirconia ◽

Partially Stabilized Zirconia ◽

Yttria Partially Stabilized Zirconia

A new brazed monolayer diamond grinding wheel is developed with the same continuous cutting edge distance on the wheel surface. Surface/subsurface damage of yttria partially stabilized zirconia (Y-PSZ) in grinding using monolayer brazed diamond wheel is analyzed. In this investigation, the influence of the maximum undeformed chip thickness (hm) on material removal mechanism is analyzed. The experiment results show that the ground surface is almost in ductile material removal mode when hm is below the critical value for Y-PSZ, otherwise it will be the combined removal modes of brittle and ductile when hm is above the critical value.

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