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Indexed by:期刊论文
Date of Publication:2009-02-01
Journal:CHINESE JOURNAL OF MECHANICAL ENGINEERING
Included Journals:CSCD、SCIE、EI、Scopus
Volume:22
Issue:1
Page Number:15-20
ISSN No.:1000-9345
Key Words:potassium dihydrogen phosphate (KDP) crystal; scratch; subsurface damage
Abstract:Potassium dihydrogen phosphate (KDP) is an important. electro-optic crystal, often used for frequency conversion and Pockels cells in large aperture laser systems. To investigate the influence of anisotropy to the depth of subsurface damage and the profiles of cracks in subsurface of KDP crystal, an experimental study was made to obtain the form of subsurface damage produced by scratches on KDP crystal in [100], [120] and [1101 crystal directions oil (001) crystal plane. The results indicated that there were great differences between depth and crack shape in different directions. For many slip planes in KDP, the plastic deformation and cracks generated under pressure in the subsurface were complex. Fluctuations of subsurface damage depth at transition point were attributed to the deformation of the surface which consumed more energy when the surface deformation changed from the mixed region of brittle and plastic to the complete brittle region along the scratch. Also, the process of subsurface damage from shallow to deep, from dislocation to big crack in KDP crystal with the increase of radial force and etch pit oil different crystal plane were obtained. Because crystallographic orientation and processing orientation was different, etching pits on (100) crystal plane were quadrilateral while on (110) plane and (120) plane were trapezoidal and triangular, respectively.