深海钛合金耐压结构蠕变特性探索研究

发布时间：2018-07-29 13:48

【摘要】：耐压结构是潜艇、潜器等得以顺利开展工作的载体和保障,钛合金以其具有高比强度、耐腐蚀、低磁性等诸多优点,在深海耐压结构中替代传统材料有明显的优势。然而,相对于传统的钢制耐压结构,钛合金的蠕变问题不容忽视。本文通过钛丝悬挂拉伸试验、理论推导、数值分析和模型试验等途径,研究了钛合金及钛合金结构的常温蠕变特性,取得了以下主要成果:1、通过常温悬挂拉伸试验,测试不同应力状态下钛合金丝蠕变变形随时间的变化规律,证实了常温蠕变与中高温蠕变的显著差异,选取了适用于钛合金常温蠕变的蠕变本构关系,并拟合蠕变参数,是进行深海耐压结构蠕变计算的前提。2、用数值方法分析了球壳和环肋圆柱壳的蠕变特性,通过系列计算给出了可供参考的蠕变变形和应力重分布特征,着重分析了肋骨形式和截面尺寸对环肋圆柱壳蠕变特性的影响,并初步研究了当模型存在初始几何缺陷或开孔时蠕变对几何缺陷幅值和稳定性的影响。3、基于一般方程,首次给出了环肋圆柱壳结构壳板和肋骨腹板蠕变变形及应力重分布的瞬态解,能够与数值解较好的吻合,为理论分析环肋圆柱壳蠕变特征提供了基础。4、本文设计了一种耐压结构蠕变测试方法,首次开展了钛合金环肋圆柱壳模型外压蠕变试验。首次测得了TC4钛合金耐压结构的压缩蠕变,并与数值计算结果进行对比,初步验证了数值计算的可靠性,为耐压结构蠕变研究提供了新方法。
[Abstract]:The pressure resisting structure is the carrier and guarantee for the submarine, submarine and so on to carry out the work smoothly. Because of its high specific strength, corrosion resistance, low magnetism and so on, titanium alloy has obvious advantage in replacing the traditional material in the deep sea pressure resisting structure. However, the creep problem of titanium alloy can not be ignored compared with the traditional steel structure. In this paper, the creep properties of titanium alloy and titanium alloy structure at room temperature are studied by means of tensile test, theoretical derivation, numerical analysis and model test of titanium wire suspension. The following main achievements have been obtained: 1, and through the tensile test of hanging tension at room temperature, the creep behavior of titanium alloy and titanium alloy structure has been studied. The variation of creep deformation of titanium alloy wire with time under different stress states is tested, and the significant difference between normal temperature creep and moderate high temperature creep is confirmed. The creep constitutive relation suitable for normal temperature creep of titanium alloy is selected and the creep parameters are fitted. The creep characteristics of spherical shell and circular cylindrical shell are analyzed by numerical method, and the creep deformation and stress redistribution characteristics for reference are given through a series of calculations. The influence of rib form and section size on creep behavior of circular cylindrical shell is analyzed, and the influence of creep on the amplitude and stability of circular cylindrical shell is studied when there are initial geometric defects or holes in the model. For the first time, the transient solution of creep deformation and stress redistribution of shell plate and rib web plate of ring-ribbed cylindrical shell structure is presented, which is in good agreement with the numerical solution. In this paper, a creep test method for pressure resistant structure is designed, and the creep test of titanium alloy cylindrical shell model under external pressure is carried out for the first time. The compressive creep of TC4 titanium alloy is measured for the first time, and the results are compared with the numerical results. The reliability of the numerical calculation is preliminarily verified, which provides a new method for the study of the creep of the compressive structure.
【学位授予单位】：中国舰船研究院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U661.42

【参考文献】