高强钢中亚稳奥氏体对断裂韧性影响的研究进展

唐景韬, 姚英杰, 张游游, 吴文华, 李宇博, 陈浩, 杨志刚

Research Progress on the Influence of Metastable Austenite on the Fracture Toughness of High-Strength Steels

TANG Jingtao, YAO Yingjie, ZHANG Youyou, WU Wenhua, LI Yubo, CHEN Hao, YANG Zhigang

图2 不同相变增韧理论采用的相变区域，相变增韧理论预测的裂纹扩展阻力曲线，及增韧效应随临界应力的变化

Fig.2 Transformation zone schematics of energy adsorption theory (a) and crack tip shielding theory (b), crack propagation resistance curve predicted by transformation toughening theory (c), and the dependence of toughening behavior on the critical transformation stress (d) (h—semi-major axis of the elliptical transformation zone, βh—semi-minor axis of the elliptical transformation zone, r—distance between the edge of transformation zone and the crack tip, θ—angle between the line which originates from the crack tip connecting the transformation-zone edge, and the crack plane, ΔK_I—increment of the stress intensity factor resulted by phase transformation, $Δ K_{I}^{C}$ —critical value of ΔK_I, Δa—crack length, $K_{I}^{C}$ —type I stress intensity factor, σ_M—critical stress for martensitic transformation)