KDP晶体单点金刚石切削脆塑转变机理的研究  

Study on the mechanism of brittle-ductile transition for turning KDP crystal with single point diamond

作　　者：王景贺[1] 陈明君[1] 董申[1] 张龙江[1] 

机构地区：[1]哈尔滨工业大学精密工程研究所,黑龙江哈尔滨150001

出　　处：《光电工程》2005年第7期67-70,88,共5页Opto-Electronic Engineering

基　　金：黑龙江省自然基金项目(E2004-26);国家自然基金项目(50405011);武器装备预言基金项目

摘　　要：加工超光滑表面的KDP晶体是现代超精密加工技术领域的重点研究课题。实验采用维氏压痕法研究KDP晶体脆性材料(001)面不同晶向的硬度、断裂韧性的变化规律。通过建立KDP晶体脆塑转变临界切削厚度模型,研究了KDP晶体金刚石切削脆塑转变机理。结果表明,脆塑转变临界最小切削厚度出现在断裂韧性最小而硬度最大的[110]方向;脆塑转变临界切削最大厚度出现在断裂韧性最大而硬度最小的[001]方向。并利用超精密机床加工了KDP晶体,加工结果与理论推导结论相符合,在[001]方向加工出表面粗糙度为7.5nm(RMS)的超光滑表面。Machining KDP crystal with an ultra-smooth surface is a key subject in the field of modern ultra-precision machining. The variations in hardness and fracture toughness of different orientations on the (001) plane of KDP crystal are studied by means of Vickers indentation. Through establishing a model of critical cutting depth during the occurrence of brittle-ductile transition of KDP crystal, the mechanism of brittle-ductile transition of KDP crystal is studied. The study shows that the minimum critical turning thickness of brittle-ductile KDP transition appears in orientation [110] with minimum fracture toughness and maximum hardness. The maximum critical turning thickness of brittle-ductile KDP transition appears in orientation [001] with maximum fracture toughness and minimum hardness. The KDP crystal is machined by an ultra-precision machine tool. Experimental results are consistent with theoretical conclusion. An ultra-smooth surface with surface roughness of 7.5 nm (RMS) is machined in orientation [001].

关 键 词：KDP晶体 金刚石切削 超精密加工 断裂韧性 

分 类 号：TH161[机械工程—机械制造及自动化]