聚变堆用钇掺杂钨合金的设计、制备及性能评价

发布时间：2018-04-28 04:54

本文选题：钨合金 + 显微结构　；参考：《北京科技大学》2017年博士论文

【摘要】：受控核聚变能被认为是一种有望解决未来社会发展所面临的能源危机的新能源。在受控核聚变能的研究过程中,面向等离子体材料(Plasma Facing Materials,PFMs)的安全稳定性及服役寿命是聚变堆能否得到工程应用的核心问题之一。钨因其高熔点、高导热率、低溅射腐蚀速率、高自溅射阈值以及低蒸气压和低的氘滞留等性能,从而被选用为国际热核聚变实验堆中的PFMs。然而,纯钨脆性大、韧脆转变温度高、再结晶温度低的缺陷却严重影响了钨在聚变堆中的使用。基于以上问题,本文采用两种不同的工艺路线(高能球磨与放电等离子体烧结相结合、高能球磨与传统工业烧结轧制相结合)制备了显微结构不同的Y2O3弥散强化钨合金。由于金属钇(Y)与氧具有较强的反应活性,能在制备过程中转化成高温稳定的Y203粒子。本文采用Y代替Y203作为掺杂剂。为了检验其是否满足PFMs的设计要求,本文研究和比较了纯钨和Y203弥散强化钨合金的力学性能、热导率、抗热瞬态热冲击性能和氘离子辐照行为。本文取得的主要研究成果如下:(1)当采用高能球磨与传统工业烧结轧制相结合工艺路线,在钨中掺杂1wt.%Y,球磨15 h,可以获得致密度可达99.3%、弥散相分布均匀、杂质含量较少、室温弯曲强度可达2153 MPa、470 K表现明显塑性变形行为的细晶Y2O3弥散强化钨合金;(2)制备工艺对Y2O3弥散强化钨合金的热导率、力学性能、抗瞬态热冲击性能最有非常重要的影响。在钨中掺杂1wt.%Y后,钨材料抵抗塑性变形的能力,抑制瞬态热冲击时钨晶晶粒长大和表面粗糙度的增加的能力得到明显的改善;(3)注氘样品温度可以显著影响钨材料在注氘条件下的起泡和氘滞留行为。在钨中掺杂1wt.%Y后,钨材料的起泡行为显著受到抑制。
[Abstract]:Controlled nuclear conversions are considered to be a promising solution to the energy crisis facing future social development. In the research of controlled nuclear conversions, the safety, stability and service life of plasma-oriented Facing materials are one of the key problems in the engineering application of fusion reactors. Because of its high melting point, high thermal conductivity, low sputtering corrosion rate, high self-sputtering threshold, low vapor pressure and low deuterium retention, tungsten has been selected as PFMsin the international thermonuclear fusion experimental reactor. However, the defects of high brittleness, high ductile-brittle transition temperature and low recrystallization temperature have seriously affected the use of tungsten in fusion reactors. Based on the above problems, Y2O3 dispersion-strengthened tungsten alloys with different microstructure were prepared by two different processing routes (high energy ball milling combined with discharge plasma sintering and high energy ball milling combined with traditional industrial sintering rolling). Because of the strong activity of yttrium yttrium and oxygen, Y203 particles can be transformed into stable Y203 particles at high temperature during the preparation process. Y is used as dopant instead of Y 203. In order to test whether the Tungsten alloy meets the design requirements of PFMs, the mechanical properties, thermal conductivity, thermal transient thermal shock resistance and deuterium irradiation behavior of pure tungsten alloy and Y203 dispersion-strengthened tungsten alloy are studied and compared. The main research results obtained in this paper are as follows: (1) when high energy ball milling is combined with traditional industrial sintering rolling, doping 1wt.Y in tungsten for 15 h, the density can reach 99.3, the dispersion phase distribution is uniform, and the impurity content is less. The preparation process of fine-grained Y2O3 dispersion-strengthened tungsten alloy with room temperature bending strength up to 2153 MPA ~ 470K has the most important influence on the thermal conductivity, mechanical properties and transient thermal shock resistance of Y2O3 dispersion-strengthened tungsten alloy. After doping with 1wt.%Y in tungsten, tungsten materials have the ability to resist plastic deformation. The ability to suppress the growth of tungsten crystal grain and increase of surface roughness during transient thermal shock is obviously improved) the temperature of deuterium implanted sample can significantly affect the foaming and deuterium retention behavior of tungsten materials under deuterium implantation. The foaming behavior of tungsten doped with 1wt.%Y was significantly inhibited.
【学位授予单位】：北京科技大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TL627;TG146.411

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