宏观深度测量压入仪器的研制

DEVELOPMENT OF MACRO-DEPTH-SENSING-INDENTATION INSTRUMENTATION

基于深度测量压入方法,以材料试验机Instron 5848 Microtester作为加载平台,外接高分辨力位移传感器,设计专用夹具,开发出该材料试验机的宏观压入功能．研究发现:对于机架柔度,无需再进行修正;对于压针接触面积,可用相关的方法计算．采用Oliver-Pharr方法处理测试数据,可获得材料的硬度和弹性模量．为了验证试验的可靠性,选用5种典型金属材料,将宏观压入测试结果与MTS Nano Indenter(?) XP测试结果进行对比,二者基本一致,其分散性均在10％以内．显示了开发传统材料试验机宏观压入测试功能的可行性．

Using the Instron 5848 Microtester equipped with an additional displacement sensor and specially designed jigs as the main loading setup, DSI（depth-sensing indentation） tests were performed on typical metallic materials at a macro range. From the indentation data, the hardness and modulus of the materials were directly extrapolated without a frame compliance calibration, with an analysis procedure proposed by Oliver and Pharr. In this analysis, the contact area was calculated for indentation depths ≥6μm from the area function of an ideal indenter tip and for depths 〈6μm from the area function suggested by Liu and Zhang. A comparison between our results and those from the MTS Nano Indenter XP shows that the repeatability is ideal, and the scatter of both hardness and modulus values is within 10%. So, it is feasible to develop the DSI capacity for traditional material testing machines.