摘要:本文利用X射线衍射(XRD)分析氧化膜的物相分析,扫描电镜(SEM/EDX)分析氧化膜表面形貌等方法,初步研究GH4169镍基高温合金的高温氧化行为。结果表明, GH4169合金的氧化膜主要是以Cr2O3、(Cr、Fe)2O3相组成的复杂氧化层构成,氧化膜周围随机分布的大颗氧化物颗粒,结合能谱分析可知,形成富Ti区,其物相为TiO2。GH4169合金在920℃下 保温10h形成的外氧化层厚度约为2-3微米,在基体表面会发生氧化形成外氧化层,外氧化层是以Cr2O3、(Cr、Fe)2O3相组成的复杂氧化层构成;而在基体内发生氧化形成内氧化层,内氧化层主要以Al2O3氧化物颗粒。外氧化层是连续致密的膜,对基体有保护的作用。GH4169合金中铬含量达到18%,合金表面会形成一层连续致密的Cr2O3膜,其稳定性较高,对基体起到较强的保护性。铌和钼元素,容易与氧气发生氧化,特别是钼元素形成的氧化膜容易挥发。Ti元素在合金的外氧化膜表面形成TiO2 颗粒,其氧化物TiO2结构疏松。加入0。45% Al元素,Al含量低不能形成Al2O3连续膜来阻止氧化的发生,从而导致氧原子沿晶界向内部发生氧化,形成内氧化。79887
毕业论文关键词:镍基高温合金 氧化膜 GH4169合金
Effect of Aluminum Titanium and Niobium on High Temperature Oxidation Behavior of a Ni-base Superalloy
Abstract:The high temperature oxidation behavior of GH4169 nickel base superalloy was studied by X - ray diffraction (XRD) analysis of the phase analysis of the oxide film and scanning electron microscopy (SEM / EDX) analysis of the surface morphology of the oxide film。 The results show that the oxide film of GH4169 alloy is mainly composed of Cr2O3, (Cr, Fe) 2O3 phase composed of complex oxide layer, the oxide film around the random distribution of large oxide particles, combined with energy spectrum analysis shows that the formation of Ti-rich, The phase is TiO2。 GH4169 alloy at 920 ℃ for 10h under the formation of the thickness of the outer oxide layer is about 2-3 microns, the surface of the substrate will be oxidized to form an external oxide layer, and in the matrix oxidation to form an internal oxide layer。 The outer oxide layer is a continuously dense membrane that protects the substrate。 GH4169 alloy in the chromium content of 18%, the alloy surface will form a layer of continuous dense Cr2O3 film, its stability is high, the matrix play a strong protective effect。 Niobium and molybdenum elements, easily oxidized with oxygen, especially molybdenum oxide oxide film is easy to volatilize。 Ti element forms TiO2 particles on the surface of the outer oxide film of the alloy, and its oxide TiO2 structure is loose。 Adding 0。45% Al element, Al content is low can not form Al2O3 to prevent the occurrence of oxidation, resulting in oxygen atoms along the grain boundary to the internal oxidation, the formation of internal oxidation。
Key words:Nickel - based superalloy Oxide film GH4169 alloy
目 录
1 绪论 1
1。1高温合金 1
1。1。1高温合金强化机理 1
1。2镍基高温合金 1
1。3镍基高温合金的发展史 2
1。4镍基合金的特性 2
1。5金属氧化机理 2
1。5。1 金属初期氧化机理 3
1。5。2 氧化膜中的应力与机制 3
1。5。3 纯金属的氧化 3
1。5。4 合金的氧化 铝钛铌等合金元素对一种镍基高温合金高温氧化行为的影响研究:http://www.youerw.com/huaxue/lunwen_92620.html