Research of Subsurface Damage Depth of Lithium Niobate Crystal by Fixed-Abrasive Lapping

The depth of surface/subsurface damage layer is the key index of surface quality of sapphire. In this paper, that depth model of the surface/subsurface damage lay characterized by the crack length was established according to the mechanical theory of indentation fracture. The cutting relation between abrasive and workpiece and the difference of the depth of subsurface damage crack are analyzed. It is preliminarily estimated that the length of sub-surface damage crack of free abrasive sapphire is about 2.46 times that of fixed abrasive when considering only the contact hardness of abrasive grain under static load. Diamond abrasives with size of W20 were adopted to carry out experiments in free and fixed lapping methods. The results show that the surface/subsurface damage depth is 9.87μm and 3.63μm respectively. It is easier to obtain good sub-surface quality by using the fixed abrasive method than free abrasive at the same particle size.

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Research on Subsurface Damage After Abrasives and Fixed-Abrasive Lapping of K9 Glass

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.487.253 ◽

2011 ◽

Vol 487 ◽

pp. 253-256 ◽

Cited By ~ 6

Author(s):

Jun Li ◽

P. Gao ◽

Yong Wei Zhu ◽

B. Li ◽

Y.L. Sun ◽

...

Keyword(s):

Surface Quality ◽

High Surface ◽

Surface Damage ◽

Subsurface Damage ◽

High Surface Quality ◽

Grain Sizes ◽

Chemical Etch ◽

Surface Damages ◽

Damage Depth ◽

Fixed Abrasive

Fixed-abrasive lapping (FAL) is a new machining technology and is adopted to manufacture hard brittle materials to obtain the high surface quality. In the same machining condition, K9 glasses are lapped by abrasives and fixed-abrasive, respectively. Two grain sizes of diamond abrasives are adopted in every lapping means. Differential chemical etch method (DCEM) is employed to measure the depth of subsurface damage (SSD) of different lapping means. Surface damages are compared by Microscope. The results show that the depth of SSD is 53 and 15.2μm after abrasives lapping (AL) by 40 and 28μm diamond abrasives. FAL with 40 and 28μm diamond abrasive leads to 4.5 and 3.4μm subsurface damage depth, respectively. FAL can get smaller surface damage and shallower depth of SSD than AL. And FAL can obtain the higher surface quality than AL.

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Study on Subsurface Damage after Fixed-Abrasive Lapping with Different Particle Size

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.175.112 ◽

2011 ◽

Vol 175 ◽

pp. 112-115 ◽

Cited By ~ 2

Author(s):

Ping Gao ◽

Jun Li ◽

Yong Wei Zhu ◽

Biao Li ◽

Yan Zhang ◽

...

Keyword(s):

Particle Size ◽

Diamond Particle ◽

Abrasive Particle ◽

Subsurface Damage ◽

Chemical Etch ◽

Surface Damages ◽

Damage Depth ◽

Fixed Abrasive ◽

K9 Glass

Differential chemical etch method (DCEM) was employed to study the effect on the surface/subsurface damage depth of K9 glass lapped by different particle sizes of fixed diamond abrasives. The advantage of DCEM is that both the lapped and substrate samples are placed in the chemical etch at the same time to decrease or eliminate the effect of etching condition variation. K9 glasses are firstly fixed-abrasive lapped with 40, 28, 14 and 10μm diamond abrasives, respectively. Surface damages of K9 glass after FAL are measured by Microscopy. The results show that the corresponding subsurface damage (SSD) depths of K9 glass are 4.5, 3.4, 2.8 and 1.6μm when the fixed diamond abrasive particle size are 40, 28, 14 and 10μm.With the decreasing of diamond particle size, the SSD depth decreases obviously and surface quality of K9 glass is improved significantly.

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