为了分析V型缺口的应力集中系数,引入Filippi缺口应力场方程,计算了对称拉伸(Ⅰ型)和反对称剪切(Ⅱ型)两种载荷类型下的应力场参数.建立拉伸载荷下的V型缺口参数化模型,通过数值计算和理论分析结果比较,验证了Filippi方程的准确性.考虑到缺口根部的微观约束效应,采用Neuber应力平均概念和虚拟缺口半径方法,获得了缺口约束因子,虚拟缺口半径等与缺口参数之间的关系.在此基础上,采用有限元方法计算了尖锐V型缺口在不同约束尺寸和缺口角度下的平均应力集中系数和等效应力集中系数,两种缺口应力集中系数偏差基本保持在10％以下,表明所求解的缺口应力集中系数具有较高的可信度.最后将缺口应力集中系数应用在焊接接头的缺口应力分析中,从而避免了因单元尺寸不同而造成的结果差异.%In order to analyze the stress concentration factor of V-notch, this paper introduced Filippi notch stress field equation. The notch stress field parameters were calculated under symmetric tensile load (ModelⅠ) and skew-symmetric shear load(ModelⅡ) . The parameterized FE model of a V-notch under tensile load was established, and the accuracy of the Filippi equation is verified by comparing the results of numerical calculation and theoretical analysis. Considering the microstructural support effect of the notch root, the relationships between support factors, fictitious notch radius and notch parameters were (adopted) obtained by introducing Neuber stress average concept and FNR. Based on the research above, the finite element method was used to analyze the average stress concentration factors and equivalent stress concentration factors of pointed V-notch with different support length and notch opening angle. The result show that the notch stress concentration factor solved have high credibility, as the deviation of the two notch SCF remained below 10％.At last, to avoid differences of the notch stress caused by different element size, the notch SCF was applied to determine the notch stress of welded joint.
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