GH132合金疲勞蠕變交互作用下裂紋擴展速率研究

The Investigation of Crack Crowth Rate under the Condition of Fatigue-Creep Interaction for GH132 Disc

摘要: 通過對650℃、不同應力條件下GH132合金的裂紋擴展速率的測定結果表明:
（1）由于GH132合金的蠕變與疲勞裂紋的擴展機構不同,使得前者有更大的環境敏感性。
（2）在疲勞蠕變交互作用條件下,裂紋的擴展過程受K_max及ΔK共同控制(K_eq=K_max+αΔK)。通常的ΔK描述法已不能全面解釋裂紋擴展速率與壽命之間的對應關系。

Abstract: The crack growth rates under the condition of fatigue-creep interaction at 650℃ were measured. The results of mesurement indicated that the crack growth rate was controlled by both Kmax and AK. In this case the effective stress indensity factor (Keq) is a suitable parametes describing the behaviour of crack propagation.Keq is equal to the sum of kmax and α'△k, Where α' was assumed as a parameter represented the effect of crack closure, and α' is a function of crack length.