论文部分内容阅读
对一种新研制的低合金高强度结构钢15MnoVNRe,采用五种热处理工艺,研究了钢中相变组织——拉状贝氏体的形成规律和形态特征,及其在解理断裂条件(—196℃)下的力学性能和断裂行为。结果表明:粒状贝氏体解理断裂的裂纹萌生与扩展行为决定于其微观组织形态特征;在试验条件下,解理断裂应力与常规力学性能参量之间存在相关关系:σ_f=—434+2.15σ_(0.2_+12.5K_(1c)MPa。基于上述结果,探讨了在具有粒状贝氏体组织形态的低合金结构钢中,提高材料低温强韧性的组织优化设计与途径.
For a newly developed 15MnoVNRe low alloy high strength structural steel, five heat treatment processes were used to study the formation and morphological characteristics of phase transitional structure - bainite in steel and its effect on cleavage and fracture conditions (- 196 ℃) under the mechanical properties and fracture behavior. The results show that the crack initiation and propagation behavior of granular bainite fracture depends on its microstructure and morphology. Under the experimental conditions, there is a correlation between cleavage fracture stress and conventional mechanical properties parameters: σ_f = -434 + 2.15 σ 0.2-0 12.5K 1c MPa.Based on the above results, the microstructure optimization design and approach to improve the low temperature toughness of low alloyed structural steels with granular bainite morphology were discussed.