基于示波冲击实验材料动态断裂韧度测试技术的研究  

STUDY ON THE EXPERIMENTAL TECHNIQUES OF DYNAMIC FRACTURE TOUGHNESS OF MATERIALS BASED ON INSTRUMENTED CHARPY IMPACT TEST

作　　者：许振琦[1] 朱世范[1] 果春焕[2] 王延春[3] 姜风春[2] 

机构地区：[1]哈尔滨工程大学机电学院,哈尔滨150001 [2]超轻材料与表面技术教育部重点实验室,哈尔滨工程大学材料科学与化学工程学院,哈尔滨150001 [3]中国兵器工业集团北京北方车辆集团有限公司,北京100072

出　　处：《机械强度》2015年第1期149-153,共5页Journal of Mechanical Strength

基　　金：国家自然科学基金(11172074)资助~~

摘　　要：采用预裂纹Charpy冲击试样,基于示波冲击试验建立了测试材料动态断裂韧度的试验方法。与以往预裂纹试样动态应力强度因子的计算方法不同,采用Timoshenko梁理论,提出了一种简单方法来计算三点弯曲试样的刚度K(a),由此建立了三点弯曲试样动态应力强度因子的计算方法,通过实验测得启裂时间,从而确定动态断裂韧度。采用有限元方法对试样动态应力强度因子的理论计算方法进行了验证。结果表明,建立的计算方法准确、可靠,避免了复杂的数值计算,便于工程应用。A measuring method was proposed to evaluate the dynamic fracture toughness of materials using pre-cracked Charpy impact specimens in this work. Different from the previous methods, a simple way to calculate the dynamic stress intensity factors of three-point bending specimen was developed based on the calculation of fracture specimen＇ s stiffness using Timoshenko beam theory. The fracture initiation time was detected experimentally and then used to determine the dynamic fracture toughness of materials. The calculated values were compared with the results obtained from finite element simulation, a good agreement was found from the comparison between the theoretical calculation and FEA, indicating that the current method proposed in this study is accurate, reliable and convenient for engineering application.

关 键 词：示波冲击 动态断裂韧性 三点弯曲试样 有限元分析 

分 类 号：O346.1[理学—固体力学]