20Cr结构钢疲劳裂纹扩展的应力强度因子范围及有效应力强度因子范围的计算  

Calculation of the Stress Intensity Range and the Effective Stress Intensity Range of the Structure Steel 20Cr

作　　者：杨秀清[1] 钟蜀晖[1] 

机构地区：[1]贵州大学土木建筑学院,贵州贵阳550003

出　　处：《贵州工业大学学报（自然科学版）》2006年第6期18-21,共4页Journal of Guizhou University of Technology(Natural Science Edition)

摘　　要：计算了20Cr结构钢疲劳长裂纹和疲劳小裂纹扩展的应力强度因子范围ΔK、有效应力强度因子范围ΔKeff,并建立了da/dN-ΔK和da/dN-ΔKeff的关系。结果表明裂纹闭合是导致长裂纹在不同应力比R时的裂纹扩展规律差异的主要原因,但它可能不是引起小裂纹、长裂纹的扩展差异的主要因素。This paper calculated the stress intensity range △K and the effective stress intensity range △K,ff of the long fatigue crack and short fatigue crack in the structure steel 20Cr, and build ed the curve of da/dN- △K and da/dN-△Keff. The result shows that the crack closure is the main reason of the difference of the da/dN -△K curve in different stress ratios of the long crack, but it is probable not the main reason of the difference of the da/dN-△K curve of the short crack and the long crack.

关 键 词：小裂纹 长裂纹 应力强度因子范围 有效应力强度因子范围 裂纹闭合 

分 类 号：TG113.255[金属学及工艺—物理冶金] TG115.57[金属学及工艺—金属学]