【作者】 张晓宇；

【导师】 任平弟；

【作者基本信息】 西南交通大学 ， 材料科学与工程， 2009， 硕士

【摘要】 能源已成为严重制约我国经济持续发展的战略问题,而核能则是解决能源问题的重要途径之一。蒸汽发生器管是核电设备中的重要组成部分,微动磨损是蒸汽发生器管破裂的主要原因之一。因此,研究蒸汽发生器管的高温微动磨损及其损伤机理对延长蒸汽发生器管服役寿命和提高蒸汽发生器管的使用可靠性具有重要意义。使用PLINT高温微动磨损试验机,在法向载荷50N和80N,位移幅值2～80μm,不同温度(25℃、300℃和400℃)条件下,研究了核电蒸汽发生器导热管材料I-800合金的微动磨损特性。在微动运行规律分析的基础上,结合光学显微镜、扫描电镜以及能谱分析,取得的研究结果如下:(1) I-800合金在三种温度下微动运行均遵循微动图理论,I-800合金微动运行区域由部分滑移区、混合区和滑移区组成。(2)当载荷和温度相同时,随着位移幅值增加,I-800合金微动运行状态经历了从部分滑移区向混合区和滑移区的规律性转变;温度改变对微动运行区域影响较小。(3)在混合区和滑移区,稳态摩擦系数随温度的升高而降低,是因为温度升高,摩擦氧化作用加剧,氧化物第三体形成并具有减膜作用;部分滑移区,温度对稳态摩擦系数影响较小。(4) I-800合金在室温(T=25℃)条件下,微动磨损机制以磨粒磨损和氧化磨损为主。而在温度分别为T=300℃和T=400℃时,I-800合金材料的磨损机制主要表现为摩擦氧化、磨粒磨损与剥层的共同作用。更多还原

【Abstract】 Energy has been a strategic problem which limits sustaining economy development of our nation.However,nuclear energy is one of the main paths to solve the energy issue.A steam generator(SG) tube materials in nuclear power plants is one of the most important components.Fretting wear has become one of the primary reason to steam generator(SG) tube cracking.So investigation on Fretting wear and damage mechanisms of steam generator(SG) tube at high temperature are of great imporptance in prolonging steam generator(SG) tube’ life and improving the reliability of steam generator(SG) tube.The fretting wear behavior of Alloy-800 steam generator tube materials has been investigatded on a Deltalab-Nene7 under normal load(80N),displacement amplitudes (2-80μm) and temperatures(25℃,300℃and 400℃).Fretting wear behaviours were analyzed in combination with microscopic exminations through optical microscope, laser confocal scanning microscopy(LCSM) and scanning microscope(SEM).The following conclusions were obtained.1.Fretting running rule of Alloy-800 steam generator tube materials obey the fretting maps theory under three temperatures.Fretting running regimes of Alloy-800 steam generator tube materials are made up of partial slip regime,mixed regime and slip regime.2.The fretting regime of Alloy-800 is transformed from partial slip regime into mixed fretting regime and gross slip regime by its fretting behavior with increasing displacement amplitude at the same normal load and temperature conditions,fretting regime almost not change with the increase of temperature.3.The friction coefficients decrease with the increase of temperature in mixed fretting regime and gross slip regime;with the temperature changes from25℃to400℃,friction oxidation have a accelerated oxidation function,oxidation body had been eased film due to wear debris in the process of fretting wear;hower, for partial slip regime the friction coefficients hardly change with the change of temperature.4.Abrasive wear and oxidation are main fretting wear mechanisms of Alloy-800 at the temperature(T=25℃).The fretting wear mechanisms of Alloy-800 exhibited mainly friction oxidation,abrasive wear and delamination mechanism at high temperatures(T=300℃and T=400℃).更多还原