球压痕仪机架柔度对硬度的影响分析与标定方法研究

Study on the effect analysis and calibration method of machine compliance on hardness for spherical indentation instrument

针对Oliver-Pharr法计算压痕硬度的精度受机架柔度影响的问题,该文将微压痕仪简化为弹簧串联模型,基于Oliver-Pharr方法,建立机架柔度对接触深度和压痕硬度误差影响的解析模型。采用有限元仿真分析,获得压痕功比值与压痕深度比值之间的函数关系,建立实际压痕深度与机架柔度无关的压痕参数的解析模型,实现机架柔度的标定。实验表明:该方法能够快速高效地对机架柔度进行标定。

For the accuracy of the indentation hardness using the Oliver-Pharr method is affected by the frame compliance, the micro -indentation instrument was simplified as a spring series model in this paper, two analytical models for the influence of frame compliance on contact depth and indentation hardness were establishedbased onthe Oliver -Pharr method. Used finite element simulation method, the relationships between the indentation work ratio and indentation depth ratio were obtained, an analytical model between the actual indentation depth and the indentation parameters independent of the frame compliancewas established, and thenthe frame compliance was calibrated. The results of indentation experiments are shown that the frame compliance can be quickly and efficiently calibrated.