本文關(guān)鍵詞： Sn納米顆粒 AZ31鎂合金 顯微組織 力學(xué)性能　出處：《大連理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：顆粒增強鎂基復(fù)合材料具有力學(xué)性能呈各向同性、制備工藝簡單、易機械加工等特點,是目前最有可能實現(xiàn)低成本、規(guī)�；a(chǎn)的鎂基復(fù)合材料。近年來,通過引入微、納米級粒子制備顆粒增強鎂基復(fù)合材料,提高鎂合金強度、塑性方面做了許多成功的嘗試,這將會拓寬鎂合金在電子、通信、現(xiàn)代汽車、航空航天等領(lǐng)域的應(yīng)用。本文選用AZ31鎂合金為基體,直流電弧等離子體法制備Sn納米顆粒并作為引入顆粒,采用攪拌鑄造法制備Mg2Sn/AZ31鎂基復(fù)合材料,并與Sn錠形式引入作對比。利用X射線衍射儀、光學(xué)顯微鏡、掃描電子顯微鏡以及室溫拉伸試驗儀等多種分析測試方法,研究Sn納米顆粒的引入對AZ31鎂合金組織性能的影響。主要結(jié)論如下：(1)直流電弧等離子體法制備的Sn納米顆粒,粒徑均勻,大小在40-80nm之間,顆粒形態(tài)為球形,表面有一層厚度約6nm的氧化物包覆。(2)無論Sn以何種形式引入,均可與Mg原位反應(yīng)生成Mg2Sn增強相。引入Sn納米顆粒時,可在基體中形成納米級Mg2Sn顆粒,但主要以團簇形式存在；Sn錠的引入則在基體中形成微米級的粗大Mg2Sn顆粒。(3)引入1wt.%Sn納米顆粒時,β-Mg17Al12相主要以骨骼狀斷續(xù)地分布在α-Mg的晶界處；由于Mg2Sn相與β-Mg17Al12相的分布存在重疊性,當(dāng)進(jìn)一步增加Sn納米顆粒的含量(3wt.%),Mg2Sn納米顆粒之間團聚加重,以“鏈狀”分布于晶界處,使得骨骼狀β-Mg17Al12又會連續(xù)地分布。(4)Sn納米顆粒的引入,使AZ31鎂合金的性能得到一定的提高,引入量為1wt.%時,抗拉強度、伸長率分別提高35.6%、83.6%,但略低于引入1wt.%Sn錠時材料的性能,這與Sn納米顆粒在熔煉過程中的燒損導(dǎo)致其實際引入量較少以及納米級Mg2Sn顆粒以團簇形式存在有關(guān)。
[Abstract]:Particle reinforced magnesium matrix composites have the characteristics of isotropic mechanical properties, simple preparation process, easy machining, and are the most likely to achieve low-cost, large-scale production of magnesium matrix composites in recent years. Through the introduction of microparticles, nano-particles to prepare particulate reinforced magnesium matrix composites, improve the strength of magnesium alloys, plastic aspects of a lot of successful attempts, which will broaden the magnesium alloy in electronics, communications, modern cars. In this paper, Sn nanoparticles were prepared by DC arc plasma method with AZ31 magnesium alloy as the substrate. Mg2Sn/AZ31 magnesium matrix composites were prepared by agitation casting and compared with Sn ingot. X-ray diffractometer and optical microscope were used. Scanning electron microscope (SEM) and room temperature tensile tester are used in this paper. The effect of Sn nanoparticles on the microstructure and properties of AZ31 magnesium alloy was studied. The main conclusions are as follows: 1) the size of Sn nanoparticles prepared by DC arc plasma method is uniform. The size is 40-80 nm, the particle shape is spherical, and the surface is covered with an oxide coating of about 6 nm.) no matter what form Sn is introduced. When Sn nanoparticles were introduced, nano-sized Mg2Sn particles could be formed in the matrix, but mainly in the form of clusters. On the other hand, the introduction of Sn ingot forms a coarse Mg2Sn particle of micron size in the matrix. 尾 -Mg17Al12 phase mainly distributes intermittently in the grain boundary of 偽 -Mg. Because the distribution of Mg2Sn phase and 尾 -Mg17Al12 phase is overlapped, the agglomeration between Mg2Sn nanoparticles is aggravated when the content of Sn nanoparticles is further increased. The "chain" distribution at grain boundaries makes the introduction of skeleton 尾 -Mg17Al12 and the introduction of nanocrystalline Sn particles can improve the properties of AZ31 magnesium alloys to a certain extent. The tensile strength and elongation increased 35.63.6when the amount of 1wt.% was introduced, but it was slightly lower than that of 1wt.Sn ingot. This is related to the small amount of Sn nanoparticles in the melting process and the existence of nanocrystalline Mg2Sn particles in the form of clusters.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB333

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 李奎,湯愛濤,潘復(fù)生;金屬基復(fù)合材料原位反應(yīng)合成技術(shù)現(xiàn)狀與展望[J];重慶大學(xué)學(xué)報(自然科學(xué)版);2002年09期

2 孫麗麗,蓋軻;納米材料的特性及用途[J];錦州師范學(xué)院學(xué)報(自然科學(xué)版);2002年03期

3 汪凌云,黃光勝,范永革,黃光杰;變形AZ31鎂合金的晶粒細(xì)化[J];中國有色金屬學(xué)報;2003年03期

相關(guān)碩士學(xué)位論文 前1條

1 鐘武波;鐵磁性納米粒子電磁性能及表面改性研究[D];大連理工大學(xué);2005年

，

本文編號：1472069