【摘要】：鎂合金具有質(zhì)輕、比強(qiáng)度高、阻尼減震和電磁屏蔽性好等優(yōu)點(diǎn),在航空航天、電子產(chǎn)品、汽車等領(lǐng)域受到越來(lái)越多的關(guān)注,并得到較為廣泛的應(yīng)用。軋制是鎂合金的一種重要的變形加工方式。目前,鎂合金在軋制過(guò)程中通常采用鋁合金軋制液,甚至進(jìn)行無(wú)潤(rùn)滑軋制。軋制過(guò)程中無(wú)潤(rùn)滑液會(huì)導(dǎo)致鎂合金軋板表面質(zhì)量差、能耗高,而鋁合金軋制液通常含有氯、硫、磷等有機(jī)化合物和金屬鹽等添加劑,此類添加劑不容易分解,使用后廢液的排放會(huì)對(duì)環(huán)境造成一定污染。本文通過(guò)摩擦磨損試驗(yàn)對(duì)鎂合金在納米基潤(rùn)滑劑潤(rùn)滑條件下的摩擦學(xué)性能進(jìn)行測(cè)試。采用激光共聚焦顯微鏡、場(chǎng)發(fā)射掃描電鏡(FESEM)、X射線光電子能譜(XPS)等手段,考察磨痕表面形貌和化合物組成成分,探討添加劑之間以及添加劑與金屬表面之間的作用機(jī)理。然后將摩擦磨損試驗(yàn)篩選的納米基潤(rùn)滑劑進(jìn)行AZ31鎂合金板材軋制,觀察在干軋和納米基潤(rùn)滑劑潤(rùn)滑條件下軋制力的變化和軋制板材表面質(zhì)量的不同。主要結(jié)果如下:(1)考察了MoS_2納米顆粒添加到5#機(jī)械油(無(wú)其他添加劑)、菜籽油和30#機(jī)械油(含添加劑)三種不同基礎(chǔ)油中的摩擦學(xué)性能,探索MoS_2納米顆粒與不同基礎(chǔ)油及摩擦副表面的作用機(jī)理。結(jié)果表明,MoS_2納米顆粒添加到5#機(jī)械油和菜籽油中均有一定的減摩抗磨作用,MoS_2納米顆粒加入5#機(jī)械油中的減摩抗磨性能優(yōu)于加入菜籽油中。而MoS_2納米顆粒加入30#機(jī)械油中的減摩抗磨性能與不含MoS_2納米顆粒的30#機(jī)械油的減摩抗磨效果相當(dāng)。(2)通過(guò)控制納米顆粒在基礎(chǔ)油中的含量和摩擦測(cè)試參數(shù),從納米顆粒成分含量、承載能力及潤(rùn)滑膜穩(wěn)定性三個(gè)方面考察了SiO_2和MoS_2分別作為潤(rùn)滑油添加劑對(duì)鎂合金的摩擦磨損性能的影響。結(jié)果表明,SiO_2納米基潤(rùn)滑油較MoS_2納米基潤(rùn)滑油具有更優(yōu)的減摩性能,而MoS_2納米基潤(rùn)滑油較SiO_2納米基潤(rùn)滑油具有更優(yōu)的抗磨性能、承載能力和潤(rùn)滑膜穩(wěn)定性。基于以上研究基礎(chǔ),然后研究了SiO_2納米顆粒和MoS_2納米顆粒復(fù)合作為潤(rùn)滑油添加劑,進(jìn)一步優(yōu)化了兩種納米顆粒單獨(dú)作為潤(rùn)滑添加劑的潤(rùn)滑性能,并深入探討了兩種納米顆粒復(fù)合添加的協(xié)同潤(rùn)滑機(jī)理。(3)通過(guò)摩擦磨損試驗(yàn)系統(tǒng)考察了石墨烯、氧化石墨烯單獨(dú)添加以及石墨烯和氧化石墨烯分別與SiO_2納米顆粒復(fù)合添加作為水基潤(rùn)滑添加劑對(duì)鎂合金的摩擦磨損性能的影響。氧化石墨烯作為水基潤(rùn)滑添加劑的潤(rùn)滑性能優(yōu)于石墨烯作為潤(rùn)滑添加劑。石墨烯與SiO_2納米顆粒復(fù)合添加起到了協(xié)同潤(rùn)滑作用比單獨(dú)石墨烯作為潤(rùn)滑液添加劑的潤(rùn)滑性能優(yōu)異。而氧化石墨烯與SiO_2納米顆粒復(fù)合添加與單獨(dú)氧化石墨烯作為潤(rùn)滑添加劑的潤(rùn)滑性能相當(dāng)。即使這樣,在復(fù)合物中SiO_2納米顆粒取代了部分氧化石墨烯降低了生產(chǎn)成本。(4)將通過(guò)摩擦磨損實(shí)驗(yàn)篩選出來(lái)的潤(rùn)滑性能優(yōu)良的SiO_2/MoS_2復(fù)合油基潤(rùn)滑液、SiO_2/石墨烯復(fù)合水基潤(rùn)滑液和SiO_2/氧化石墨烯復(fù)合水基潤(rùn)滑液在AZ31鎂合金軋制過(guò)程中應(yīng)用。相對(duì)于干軋來(lái)說(shuō),在SiO_2/MoS_2復(fù)合油基潤(rùn)滑液潤(rùn)滑條件下壓下量為10%對(duì)AZ31鎂合金軋制,軋制力和軋后板材表面粗糙度分別降低了14.5%和55.9%。石墨烯/SiO_2復(fù)合水基潤(rùn)滑液潤(rùn)滑條件下,軋制力和軋后板材表面表面粗糙度相對(duì)于干軋分別降低了12%和42.4%。氧化石墨烯/SiO_2復(fù)合水基潤(rùn)滑液潤(rùn)滑條件下,軋制力和軋后板材表面表面粗糙度相對(duì)于干軋分別降低了13.1%和28.8%。(5)總結(jié)認(rèn)為,SiO_2/MoS_2復(fù)合油基潤(rùn)滑液和SiO_2/石墨烯復(fù)合水基潤(rùn)滑液中兩種納米顆粒起著協(xié)同潤(rùn)滑作用,均比單獨(dú)一種納米顆粒作為潤(rùn)滑添加劑的潤(rùn)滑性能優(yōu)異。而氧化石墨烯/SiO_2納米復(fù)合水基潤(rùn)滑液的潤(rùn)滑性能與純氧化石墨烯水基潤(rùn)滑液的潤(rùn)滑性能相當(dāng),但其作為潤(rùn)滑液比純氧化石墨烯潤(rùn)滑液的成本降低。
[Abstract]:Magnesium alloys have attracted more and more attention in aerospace, electronic products, automotive and other fields because of their advantages of light weight, high specific strength, good damping and electromagnetic shielding. Rolling is an important deformation processing method of magnesium alloys. At present, aluminum alloy is usually used in the rolling process of magnesium alloys. In the rolling process, no lubricant will lead to poor surface quality and high energy consumption of magnesium alloy rolling plate, while aluminum alloy rolling fluid usually contains chlorine, sulfur, phosphorus and other organic compounds and metal salts additives, such additives are not easy to decompose, waste liquid discharge after use will cause certain environmental pollution. The tribological properties of magnesium alloys lubricated with nano-based lubricants were tested by friction and wear tests. The surface morphology and composition of the wear scars were investigated by means of laser confocal microscopy, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and the relationship between additives and metal surface was discussed. The main results are as follows: (1) The addition of MoS_2 nanoparticles to 5# mechanical oil (without other additives) was investigated. Tribological properties of rapeseed oil and 30 # mechanical oil (containing additives) were investigated to explore the mechanism of action of MoS_2 nanoparticles on the surfaces of different base oils and friction pairs. The friction and anti-wear properties of MoS_2 nanoparticles in 30# mechanical oil are similar to those of 30# mechanical oil without MoS_2 nanoparticles. (2) By controlling the content of nanoparticles in the base oil and the friction test parameters, the content of nanoparticles, the load-carrying capacity and the lubricating film are stable. The effects of SiO_2 and MoS_2 as lubricating oil additives on the friction and wear properties of magnesium alloys were investigated qualitatively in three aspects. The results showed that SiO_2 nano-based lubricating oil had better antifriction performance than MoS_2 nano-based lubricating oil, and MoS_2 nano-based lubricating oil had better antiwear performance, load-bearing capacity and wear resistance than SiO_2 nano-based lubricating oil. Based on the above research, the lubrication performance of SiO_2 nanoparticles and MoS_2 nanoparticles as lubricant additives was further optimized, and the synergistic lubrication mechanism of the two nanoparticles was discussed in detail. (3) Friction and wear of the lubricant were studied. The effects of graphene, graphene oxide and graphene oxide and SiO_2 nanoparticles on the friction and wear properties of magnesium alloys were investigated. The lubrication performance of graphene oxide as water-based lubrication additive was better than that of graphene as lubrication additive. The lubrication performance of graphene oxide and SiO_2 nanoparticles is comparable to that of graphene oxide alone. Even so, SiO_2 nanoparticles replace SiO_2 nanoparticles in the composites. (4) SiO_2/MoS_2 composite oil-based lubricants, SiO_2/graphene composite water-based lubricants and SiO_2/graphene oxide composite water-based lubricants with excellent lubrication performance screened by friction and wear tests were used in the rolling process of AZ31 magnesium alloy. Compared with dry rolling, SiO_2/MoS_2 composite lubricants were used in the rolling process of AZ31 magnesium alloy. The rolling force and surface roughness of AZ31 magnesium alloy after rolling were reduced by 14.5% and 55.9% respectively by 10% reduction under the lubricating condition of compound oil-based lubricant. The rolling force and surface roughness of AZ31 magnesium alloy after rolling were reduced by 12% and 42.4% respectively compared with that of dry rolling under the lubricating condition of graphene/SiO_2 compound water-based lubricant. The rolling force and the surface roughness of rolled sheet decreased by 13.1% and 28.8% respectively compared with dry rolling under O_2 complex water-based lubricant lubrication condition. (5) It is concluded that SiO_2/MoS_2 complex oil-based lubricant and SiO_2/graphene complex water-based lubricant play a synergistic lubrication role, both of which are better than single nanoparticle as lubricant. The lubrication performance of graphene oxide/SiO_2 nanocomposite water-based lubricant is similar to that of pure graphene oxide water-based lubricant, but its cost is lower than that of pure graphene oxide lubricant.
【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：TG339;TH117.22

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 劉躍文;鄧順柳;謝素原;黃榮彬;鄭蘭蓀;;氧化石墨烯的還原和烷基化及其儲(chǔ)能性能研究[J];廈門(mén)大學(xué)學(xué)報(bào)(自然科學(xué)版);2014年05期

2 喬玉林;趙海朝;臧艷;張慶;;多層石墨烯水分散體系的摩擦磨損性能研究[J];摩擦學(xué)學(xué)報(bào);2014年05期

3 賈園;顏紅俠;公超;馮逸晨;;石墨烯的表面改性及其在摩擦領(lǐng)域中的應(yīng)用[J];材料導(dǎo)報(bào);2013年05期

4 方建華;潘復(fù)生;陳波水;吳江;董凌;;硫化菜籽油潤(rùn)滑添加劑對(duì)鋼-鎂摩擦副摩擦學(xué)性能的影響(英文)[J];Transactions of Nonferrous Metals Society of China;2011年12期

5 方建華;陳波水;潘復(fù)生;董凌;;硼化蓖麻油潤(rùn)滑添加劑對(duì)鋼-鋼和鋼-鎂摩擦副摩擦學(xué)性能的影響[J];石油煉制與化工;2010年09期

6 方建;趙源;;潤(rùn)滑添加劑的磨損自補(bǔ)償摩擦學(xué)效應(yīng)[J];材料保護(hù);2006年06期

7 歐忠文;陳國(guó)需;張?jiān)茟?徐濱士;楊漢民;;油潤(rùn)滑納米添加劑摩擦學(xué)設(shè)計(jì)及研究中幾個(gè)值得商榷的問(wèn)題[J];潤(rùn)滑與密封;2006年02期

8 范才河;陳剛;嚴(yán)紅革;陳振華;;稀土在鎂及鎂合金中的作用[J];材料導(dǎo)報(bào);2005年07期

9 方建華,陳波水,董凌,王九;酰胺型改性菜籽油潤(rùn)滑添加劑對(duì)鋼-鋼摩擦副和鋼-鋁摩擦副摩擦磨損性能的影響[J];摩擦學(xué)學(xué)報(bào);2005年02期

10 方建華,陳波水,黃偉九,郭小川,張斌;磷氮化改性菜籽油潤(rùn)滑添加劑的制備及其摩擦學(xué)性能[J];摩擦學(xué)學(xué)報(bào);2001年05期

相關(guān)博士學(xué)位論文 前1條

1 胡坤宏;納米二硫化鉬的形態(tài)可控合成及其催化與潤(rùn)滑性能研究[D];合肥工業(yè)大學(xué);2010年

，

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