IN SITU STRESS MEASUREMENT BY NEUTRON DIFFRACTION DURING TENSION - COMRESSION DEFORMATION(BAUSCHINGER EFFECT)IN NODULAR GRAPHITE CAST IRON
Mechanical properties of two kinds of nodular graphite cast irons with different microstructures were studied by in situ neutron diffraction during tension - compression deformation with a time of flight method. It is found that in a cast iron consisting of pearlite and ferrite, the soft phase ferrite influences the yield point and that pearlite brings high work hardening. By unloading after tensile deformation up to a certain plastic strain, large compressive residual lattice strain for ferrite phase remains while tensile for cementite in a cast iron consisting of pearlite and ferrite. This is the reason why the ferrite-pearlite matrix iron shows larger Bauschinger effect. Stress portioning between hard grain oriented 200 with respect to the loading direction and soft grain 110 is also found to cause the Bauschinger effect. They hysteresis loop for the applied stress versus lattice strain is found to differ depending on grain orientation hkl, suggesting different fatigue damage in grain by grain.
D.NAITO Y.TOMOTA S.HARJO S.KUBOTA
Graduate student,Ibaraki University,4-12-1,Nawanarusawa,Hitachi,Ibaraki,Japan Graduate School of Science and Engineering,Ibaraki,University,4-12-1,Nawanarusawa,Hitachi,Ibaraki,Ja J-PARC Center,Japan Atomic Energy Agency,Shirakata-Shirane,2-4,Tokai,Ibaraki,Japan Hitachi Construction Machinery Co.,Ltd.,650,Kandatsu,Tsuchiura,Ibaraki,Japan
国际会议
日本
英文
543-546
2011-04-01（万方平台首次上网日期，不代表论文的发表时间）