摘要
以S355、Q345D为对象,研究了两种材料自室温至-100℃温度范围内的力学性能及断裂机制。结果表明两种金属材料的断裂韧性则随温度的降低而降低;屈服强度、抗拉强度则随温度的降低而升高。断面收缩率、延伸率以及缺口敏感系数均未出现明显降低的现象。由于试验材料塑性很好产生缺口强化效应,使得缺口材料的抗拉强度高于光滑试样。从微观机制上看,随着温度的降低,材料的微观断口形貌由韧窝状逐步转化为准解理。
The mechanical properties of S355, Q345D were studied. The test temperature was from room temperature to - 100 ℃. The results show that as the temperature dropped, the fracture toughness of the two materials decreased too. At low temperature the yield strength and tensile strength of the metallic ma- terials increased greatly. The elongation A, cross-section Z and notch sensitive coefficient qe haven＇ t signif- icantly changed. Due to the notch strengthening effect, their RmHwere much higher than Rm. While from the micro-mechanism point of view, the fracture mophology changed from dimple to quasi-cleavage as the tem- perature decreased.
出处
《低温工程》
CAS
CSCD
北大核心
2012年第5期54-57,62,共5页
Cryogenics
关键词
低温
断裂韧性
断口形貌
low temperature
fracture toughness
fracture morphology
