摘要 新型钛合金随着科技的发展，已经从高精尖行业逐渐的转向民用的行业，钛及钛 合金的发展前景一片良好。然而钛合金的发展过程中仍然具有许多的问题，对于新型 钛合金研究发展越发的重要。由于钛合金的结构中或多或少都会存在一些初始的细微 裂纹，而这些细纹的裂纹会随着环境的变化和交变载荷的作用而变大从而导致结构的 破坏，这就会导致工程的质量受损，因此本文我们主要探讨的就是裂纹的扩展对钛合 金的影响。95195

本文中采用数值模拟的方法来研究钛合金的裂纹扩展速率，数值模拟是建立在有 限元法的思想基础上的一种使用计算机来模拟材料所会发生的应力和应变的研究思 路。本文主要研究的是耐压壳体上的钛合金的裂纹扩展速率，通过施加恒定荷载的方 法来模拟实际上钛合金结构在一定水深下工作的持续压力，同时也针对不同保载时间 对裂纹扩展的速率影响开展研究。在研究过程中，本文利用了 abaqus 和 zencrack 两种 有限元软件针对 60s 和 120s 两组保载时间进行有限元数值模拟研究，并对 60s 和 120s 两组数值模拟结果进行了对比分析。最后，把数值模拟结果和实验结果进行了对比分 析，得到了较好的结果。

毕业论文关键词：新型钛合金，数值模拟，paris 公式，裂纹扩展速率

Abstract With the development of science and technology, the new titanium alloy has gradually shifted from the high-tech industry to the civilian industry, titanium and titanium alloy development prospects are good。However, the development of titanium alloy process still has many problems, the development of new titanium alloy research more important。Due to the structure of the titanium alloy more or less there will be some initial fine cracks, and these fine lines of the cracks will change with the environment and the role of alternating load and thus lead to structural damage, which will lead to engineering Of the quality of damage, so this article we mainly explore the expansion of the impact of the impact of titanium alloy。

In this paper, the numerical simulation method is used to study the crack propagation rate of titanium alloy。 Numerical simulation is based on the idea of finite element method, which is used to simulate the stress and strain of the material。 In this paper, the crack propagation rate of titanium alloy on pressure-resistant shell is studied, and the constant pressure of titanium alloy structure in a certain depth is simulated by applying constant load method。 At the same time, The impact of the rate to carry out research。 In the esearch process, this paper uses the finite element software of abaqus and zencrack to analyze the load time of 60s and 120s in two groups, and compares the numerical simulation results of 60s and 120s。 Finally, the numerical simulation results and experimental results were compared and analyzed, and good results were obtained。

Keywords:New titanium alloy, numerical simulation, , paris formula, experimental design,

目 录

第一章 绪论 1

1。1 研究背景及意义 1

1。2 钛合金在船舶领域的研究现状与前景 1

1。2。1 钛合金的现状 1

1。2。2 钛合金的前景 2

1。3 钛合金疲劳裂纹扩展行为研究 3

1。4 断裂力学 3

第二章 裂纹扩展速率基础理论 5

2。1 保载-疲劳裂纹扩展的概念