本文選題：機(jī)械合金化 + MCrAlY�。� 參考：《南京航空航天大學(xué)》2010年碩士論文

【摘要】： 在機(jī)械合金化過(guò)程中,金屬粉末在經(jīng)歷冷焊和細(xì)化的同時(shí),其中一部分粉末會(huì)吸附在磨球表面及球磨罐的罐壁上,經(jīng)過(guò)反復(fù)擠壓和冷焊,形成一定厚度的涂層。根據(jù)這一原理,本文選取兩種粉末體系NiCrAl·Y_2O_3和NiCrAlCo·Y_2O_3作為原始粉末,配以一定的球磨工藝參數(shù),在管狀碳鋼材料內(nèi)壁制備MCrAlY涂層,并有選擇地對(duì)制得的合金層進(jìn)行激光重熔。 采用X射線衍射(XRD)、掃描電鏡(SEM)、能譜儀(EDS)等對(duì)合金層進(jìn)行顯微組織、化學(xué)成分和相結(jié)構(gòu)分析,并進(jìn)行顯微硬度測(cè)試、高溫氧化實(shí)驗(yàn)、劃痕實(shí)驗(yàn)來(lái)測(cè)試合金層性能。 首先以NiCrAl·Y_2O_3為合金層原始粉末,在碳鋼基體表面成功制得了NiCrAlY合金層。研究表明,球磨轉(zhuǎn)速和球磨時(shí)間對(duì)合金層的形成都具有較大影響,在400 r/min球磨10h時(shí)獲得合金層厚度最大(約35μm),此時(shí)合金層硬度最高且抗高溫氧化性最好。 在同樣的工藝參數(shù)條件下,以NiCrAlCo·Y_2O_3作為合金層原始粉末獲得的合金層的厚度有很大的提高。在400r/min球磨10h時(shí)形成的合金層厚度比NiCrAlY合金層大約15μm,且合金層的致密性、顯微硬度、抗高溫氧化性都得到了提高。 選擇400r/min球磨10h獲得的合金層進(jìn)行激光重熔,重熔后合金層的致密性得到提高,合金層-基體結(jié)合界面消失,合金層元素成分發(fā)生稀釋,且顯微硬度分布發(fā)生改變。本文還重點(diǎn)探討了機(jī)械合金化技術(shù)制備合金層的機(jī)理和MCrAlY合金層的抗高溫氧化機(jī)理。
[Abstract]:In the process of mechanical alloying, some of the metal powder will be adsorbed on the surface of the grinding ball and the tank wall of the ball mill tank during cold welding and refinement, and a certain thickness of coating will be formed after repeated extrusion and cold welding. According to this principle, two kinds of powder systems, NiCrAl Y_2O_3 and NiCrAlCo Y_2O_3, were selected as raw powder, and some parameters of ball milling were used to prepare MCrAlY coating on the inner wall of tubular carbon steel, and the alloy layer was selectively remelted by laser. The microstructure, chemical composition and phase structure of the alloy layer were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), SEM and EDS. The microhardness test, high temperature oxidation test and scratch test were carried out to test the properties of the alloy layer. Firstly, NiCrAl Y_2O_3 was used as the original powder of alloy layer, and the NiCrAlY alloy layer was successfully prepared on the surface of carbon steel substrate. The results show that the speed and time of ball milling have great influence on the formation of alloy layer. The thickness of alloy layer is the largest (about 35 渭 m) after 10 h ball-milling for 400 r/min. The hardness of alloy layer is the highest and the oxidation resistance at high temperature is the best. Under the same process parameters, the thickness of the alloy layer obtained by using NiCrAlCo Y_2O_3 as the original powder of the alloy layer is greatly improved. The thickness of the alloy layer formed after 10 hours of 400r/min milling is about 15 渭 m than that of the NiCrAlY alloy layer, and the densification, microhardness and high temperature oxidation resistance of the alloy layer are improved. After laser remelting of the alloy layer obtained by 400r/min ball milling for 10 h, the densification of the alloy layer was improved, the interface between the alloy layer and the matrix disappeared, the element composition of the alloy layer was diluted, and the microhardness distribution was changed. The mechanism of preparing alloy layer by mechanical alloying and the mechanism of high temperature oxidation resistance of MCrAlY alloy layer are also discussed in this paper.
【學(xué)位授予單位】：南京航空航天大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2010
【分類號(hào)】：TF123.111

【引證文獻(xiàn)】

相關(guān)期刊論文 前1條

1 馮亮;;機(jī)械合金化Fe-40Al合金粉末工藝研究[J];熱處理技術(shù)與裝備;2012年04期

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本文編號(hào)：1811361