钛合金载人球壳的疲劳寿命可靠性分析

本文通过引入一种改进的裂纹扩展率表达式,首先给出了深海钛合金载人球壳的疲劳可靠性模型,在对模型中各随机变量的统计特征进行分析的基础上,采用ISPUD软件中的重要样本法,计算了载人球壳的疲劳可靠性指标,证明载人球壳的疲劳强度是符合设计要求的.然后,通过对各参数的灵敏度进行分析发现,随机变量m、A、Deepth、αre对最终疲劳可靠性有显著影响,必须在设计加工阶段给予足够重视,而随机变量m与A、αre与α的相关系数对最终疲劳可靠性影响不大,在实际计算中可以忽略.

Fatigue life reliability analysis of Titanium manned spherical shell

After introduced an expression of fatigue crack growth rate,the fatigue reliability model of Titanium manned spherical shell is presented.Based on the deep analysis of the statistical characteristics of random variables,the reliability results,calculated by using the Importance Sampling Method implanted in the software ISPUD,proved the fatigue life of the spherical shell is secure.The subsequent sensitivity analysis results of random variables show that the variables of m,A,Deepth,are have significant affection on the reliability of fatigue life and must be focused on during design and manufacturing,while the correlation coefficients between m and A,are and a have less affection and even can be neglected.