基于图像处理与仿真的钨合金力学性能分析研究

发布时间：2018-04-26 17:09

  本文选题：钨合金 + 高温拉伸　； 参考：《西安建筑科技大学》2017年硕士论文

【摘要】：钨合金由于其独特的力学性能而被广泛用于民用工业与军工业方面。随着现代技术的不断发展,钨合金逐步取代贫铀合金成为穿甲弹弹芯的主材料。鉴于钨合金优异力学性能和在军事领域的重要地位,研究者们对于钨合金在不同试验条件下的力学性能进行了更深一步地研究。然而在相关研究中,由于钨金属的稀有性以及试验过程中的环境控制等问题,导致进行大量重复性试验的可行性不高。针对这一问题,在有限的试验基础上,利用计算机辅助软件与试验相结合的研究方法是可行的,且研究前景十分广阔。本文以钨合金中的93WNiFe合金为主要研究对象,以高温拉伸试验为基础,综合运用有限元仿真软件以及数字图像处理技术,分析研究了93WNiFe合金在高温拉伸作用下的力学性能变化以及微观金相组织变化的特性及规律,在研究金属材料的宏微观力学性能方面提出了一种有效的研究思路及方法。通过使用电液伺服试验机与高温加热炉对钨合金进行常温及高温拉伸试验,使用金相显微镜与场扫描电镜对金相组织进行观测采集,分析温度对于钨合金力学性能的影响得出:(1)随着温度的升高钨合金的强度逐渐降低,其中抗拉强度与断裂强度的变化规律基本相同,屈服强度变化较为平缓;(2)伴随着温度的升高,钨合金的塑性出现高-低转化现象,在400℃时塑性达到最佳。利用Ansys/Ls-dyna与HyperMesh有限元分析软件对钨合金进行常温及高温热力耦合仿真模拟,通过模拟结果与试验结果对比分析得出:(1)模拟计算的强度与试验强度基本吻合,证明了有限元仿真的可行性及正确性;(2)通过合理添加失效准则,模拟出拉伸断裂时的状态并对断裂后的断口进行分析,得出其断面收缩率变化与真实试验塑性变化规律一致,出现高-低转换现象;(3)预测性分析900℃时的拉伸力学性能,模拟数据符合真实力学性能变化趋势。通过使用数字图像处理技术对钨合金的金相组织进行分析,以Matlab图像处理为主要手段,运用改进分水岭变化分割及矩形拟合的方法,分析微观金相组织中钨颗粒的变形,并对金相组织进行定量分析,得出高温拉伸作用下钨合金宏观塑性变化规律是由于其微观尺度变化所引起的。以试验为基础,通过使用有限元软件仿真与数字图像处理技术不仅可以高效、准确地对钨合金高温拉伸力学性能进行分析,且具有一定的经济效益。
[Abstract]:Tungsten alloys are widely used in civil and military industries because of their unique mechanical properties. With the development of modern technology, tungsten alloy has gradually replaced depleted uranium alloy as the main material of armour-piercing projectile. In view of the excellent mechanical properties of tungsten alloys and their important position in the military field, researchers have studied the mechanical properties of tungsten alloys under different experimental conditions. However, due to the rarity of tungsten metal and the environmental control during the test, it is not feasible to carry out a large number of repetitive tests. In order to solve this problem, it is feasible to combine the computer aided software with the experiment on the basis of limited experiment, and the research prospect is very broad. In this paper, the 93WNiFe alloy in tungsten alloy is taken as the main research object, based on the high temperature tensile test, the finite element simulation software and digital image processing technology are used synthetically. The changes of mechanical properties and microstructure of 93WNiFe alloy under high temperature tension were analyzed and studied. An effective research method was put forward to study the macro and micro mechanical properties of metal materials. The tensile tests of tungsten alloy at room temperature and high temperature were carried out by using electro-hydraulic servo testing machine and high temperature heating furnace. Metallographic microscope and field scanning electron microscope were used to observe and collect the microstructure of tungsten alloy. By analyzing the effect of temperature on the mechanical properties of tungsten alloy, it is concluded that the strength of tungsten alloy decreases gradually with the increase of temperature, and the change of tensile strength and fracture strength is basically the same. With the increase of temperature, the plasticity of tungsten alloy appears high to low conversion phenomenon, and the plasticity reaches the best at 400 鈩，

本文编号：1806899