On the standards and practices for miniaturized tensile test – A review

Abstract

• Miniaturized Tensile Test (MTT) is extremely sensitive to specimen size effects and data deviation or scattering in experiment. • Guidelines for small specimen design are summarized and extended. • Data processing techniques can help to optimize the design of small specimens and reduce the errors in MTT. Miniaturized Tensile Test (MTT), as an important type of Small Specimen Test Technology (SSTT), has gained increasing attentions in the nuclear industry and other fields. However, MTT faces great challenges because the test results may deviate from standard specimens due to specimen size effects and may exhibit large scatters caused by fabrication imperfection. In order to improve the reliability of MTT, many efforts have been made during the past several decades, and various issues regarding on the MTT have been studied. This paper reviews and analyzes the previous studies of specimen size effects on mechanical properties and summarizes the design guidelines for MTT proposed in previous literatures. The previous specimen designs for standard and small specimens have also been reviewed briefly. The SSTT including specimen preparation, testing operation, measurements of stress and strain also have been addressed in this study, since the testing results of SSTT are sensitive to dimensional deviations, surface defects, measurement errors, etc. In addition, data analysis schemes such as elongation conversion with simple formulae or even FEM simulation have been discussed.