工程科学学报2016，Vol.38Issue(4)：522-531,10.DOI:10.13374/j.issn2095-9389.2016.04.011
微观组织对高速车轮钢解理断裂应力的影响
Effect of microstructure on the cleavage fracture stress of high-speed railway wheel steel
摘要
Abstract
The microstructures with different grain sizes and pearlite interlamellar spacings of high-speed railway wheel steel with a carbon mass fraction of 0. 54% were achieved by heat treatment at different austenitizing temperatures and cooling rates. Notched 3-point bending (3PB) bars and tensile specimens with different microstructures were tested at temperatures from -120℃ to 20℃. The stress distribution ahead of the notch tip was calculated by a two-dimensional plane strain finite element method. The fracture surfaces of the 3PB specimens were observed by scanning electron microscopy and the cleavage initiation site was located. The cleavage fracture stress of specimens with different microstructures was measured. It is shown that the cleavage fracture stress depends on the microstruc-ture when the cleavage critical event is propagation-controlled. The characteristic size of un-propagated microcracks decreases by grain refinement, the decrease of pearlite interlameller spacing is be propitious to increase the effective surface energy of the pearlite micro-structure, so the cleavage fracture stress increases with decreasing grain size and pearlite interlameller spacing.关键词
车轮钢/微观组织/解理断裂/断裂应力Key words
wheel steel/microstructure/cleavage fracture/fracture stress分类
矿业与冶金引用本文复制引用
龚帅,任学冲,陈刚,赵海,江波..微观组织对高速车轮钢解理断裂应力的影响[J].工程科学学报,2016,38(4):522-531,10.基金项目
国家自然科学基金资助项目(51171020,U1234207) （51171020,U1234207）
国家重点基础研究发展计划资助项目(2015CB654800) （2015CB654800）
