Impact Toughness of Low Alloy Steel in Relation to Microstructure
김지혁Ji Hyuck Kiehm, 맹선재Sun Chae Maeng, 김철중Chul Chung Kim
Abstract
Impact toughness of 0.36% C-Ni-Cr-Mo steel, whose composition is similar to the AISI 4340 steel, has been studied in relation to microstructures: tempered martensite, tempered lower bainite +10% martensite and tempered upper bainite. The transition temperature determined by the average energy criterion, has been found to be lowest in the tempered martensite and highest in the tempered. upper bainite. The relation between impact toughness end distribution of cementite precipitates in the microstructures has been discussed.