文献类型：期刊文献

英文题名：Evaluation of weibull parameters by different small punch tests samples based on beremin model

作者：Guan, Kaishu[1]; Guo, Linling[1]; Fu, Mingxue[1]

机构：[1] School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China

年份：2017

卷号：1A-2017

外文期刊名：American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP

收录：EI(收录号：20174704418681)

语种：英文

外文关键词：Pressure vessels - Scanning electron microscopy - Weibull distribution - X ray diffraction - Ductility - Electric discharges - Materials handling equipment

摘要：Small punch testing technology is used for quantifying the mechanical properties of bulk materials with greatly reduced volume. However, as the volume decrease, the ductile to brittle transition region of the specimen will move to lower temperature. That means a small punch specimen and a bulk specimen may fracture under different regime. For this case, it's difficult to obtain fracture toughness of bulk materials from the small punch tests. In this paper, a new approach, which is based on Beremin local approach, to evaluate the Weibull parameters of bulk materials in the ductile to brittle transition region by small punch tests has been proposed. This paper focuses on the choice of specimen types of small punch test based on Beremin model. Four different types of specimens were tested at ductile to brittle transition region. i.e. (a)two kinds of linear notched small punch test specimen (LNSP), (b) two kinds of center holed small punch test specimen (CHSP). All notches of the specimens were machined by electric discharge method, and both sides of the specimens were grinded and polished. The results showed that 0.5mm CHSP (center holed small punch test specimen) is the best choice for small punch test based on Beremin model according to experimental curves, SEM (scanning electron microscope) analysis, and result of finite element simulation. Furthermore, the cumulative failure probability in ductile-to-brittle transition region by small punch tests was obtained and the method of calculating Weibull parameters (m,σu) is analyzed. ? 2017 ASME.