金相显微镜畸变的测量不确定度评定

Evaluation of Uncertainty in Measurement of Etallographic Microscope Distortion

畸变能够反映金相显微镜实际像与理想像的偏差,是金相显微镜性能准确可靠的重要技术指标。依据《测量不确定度评定与表示》校准规范,对金相显微镜畸变测量过程进行了研究,建立畸变测量结果的不确定度评定数学模型,全面分析不确定度来源,评定金相显微镜畸变测量结果的不确定度。结果表明:取包含因子k=2,置信水平为95%时,在总放大倍率为50×、100×、200×、500×和1000×条件下,金相显微镜的相对畸变测量结果分别为(0.5±0.4)%、(0.3±0.6)%、(1.3±0.4)%、(0.4±0.4)%、(0.9±0.1)%,测量结果的不确定度主要来源于畸变测量系统和重复性测试。

Distortion can reflect the deviation between the actual image and the ideal image of a metallographic microscope,and is an important technical indicator for accurate and reliable performance of metallographic microscopes.According to the calibration standard"Evaluation and Representation of Measurement Uncertainty",the distortion measurement process of the metallographic microscope was studied,the mathematical model for the uncertainty evaluation of the distortion measurement results was established,the sources of uncertainty were comprehensively analyzed,and the uncertainty of the distortion measurement results of the metallographic microscope was evaluated.The results show that when the coverage factor k=2,the confidence level is 95%,under the condition of the total magnifications is 50×,100×,200×,500×and 1000×,the relative distortion measurement results of the metallographic microscope is(0.5±0.4)%,(0.3±0.6)%,(1.3±0.4)%,(0.4±0.4)%,(0.9±0.1)%,respectively.The uncertainty of the measurement results mainly comes from the distortion measurement system and repeatability test.