發(fā)布時(shí)間：2018-05-19 09:59

  本文選題：激光噴丸 + TC4鈦合金　； 參考：《江蘇大學(xué)》2017年碩士論文

【摘要】：鈦合金是海洋、航天工程中常用的金屬材料,服役環(huán)境對(duì)其抗氫脆性能提出了更高的要求。目前常采用表面改性方法來提高其表面機(jī)械性能。激光噴丸是利用激光沖擊波效應(yīng)在合金表層引入殘余壓應(yīng)力從而實(shí)現(xiàn)表面改性的一項(xiàng)新技術(shù),其具有強(qiáng)化效果更優(yōu)、可控性強(qiáng)且加工更為柔性化等優(yōu)點(diǎn)。本文以典型TC4鈦合金為研究材料,開展激光噴丸及電解充氫試驗(yàn),通過研究激光噴丸對(duì)TC4鈦合金充氫前后表層顯微硬度、微觀組織、拉伸力學(xué)性能及宏觀微觀斷口形貌的影響,探討激光噴丸TC4鈦合金抗氫脆機(jī)理,其核心研究?jī)?nèi)容如下:(1)從理論上分析了激光沖擊波作用于合金表面的強(qiáng)化機(jī)理,研究了TC4鈦合金在高應(yīng)變率強(qiáng)烈塑性變形條件下的微觀結(jié)構(gòu)響應(yīng)機(jī)理,制定激光噴丸TC4鈦合金的噴丸路徑和試驗(yàn)參數(shù),揭示了氫擴(kuò)散行為及其影響因素,探討了激光噴丸抗氫脆機(jī)理。(2)比較了噴丸與未噴丸TC4鈦合金在電解充氫前后微觀組織和顯微硬度的差異。根據(jù)激光噴丸強(qiáng)化引入殘余壓應(yīng)力分布原理,分析激光噴丸對(duì)氫滲透影響機(jī)制。結(jié)果顯示:激光噴丸在TC4鈦合金表層引入幅值較大的殘余壓應(yīng)力,并使TC4鈦合金表層晶粒細(xì)化,電解充氫過程中進(jìn)入試樣的氫濃度隨晶粒尺寸的減小而降低,合金氫脆敏感性降低;激光噴丸后合金的硬度提高,經(jīng)電解充氫處理后出現(xiàn)氫致硬化現(xiàn)象,并且隨著激光功率密度增加,氫致硬化率增速趨緩,激光噴丸受氫的影響變小,激光噴丸提高了TC4鈦合金抗氫脆性能。(3)對(duì)噴丸與未噴丸的TC4鈦合金在電解充氫前后進(jìn)行室溫慢拉伸試驗(yàn),研究其力學(xué)性能變化。試驗(yàn)結(jié)果表明:激光噴丸提高了TC4鈦合金抗拉強(qiáng)度及延伸率,并且隨激光功率密度的增加,其抗拉強(qiáng)度及延伸率也增加;經(jīng)電解充氫處理后,TC4鈦合金抗拉強(qiáng)度及延伸率均降低,并且隨激光功率密度的增加,氫致延伸率損失降低,TC4鈦合金氫脆敏感性隨激光功率密度的提高逐漸減小。觀察試樣斷口形貌,發(fā)現(xiàn)其微觀斷口均為典型韌窩形貌,激光噴丸后韌窩更深且更大并且均勻,顯示出更好的韌性;經(jīng)電解充氫處理后,未噴丸的TC4鈦合金出現(xiàn)準(zhǔn)解理斷裂,韌性變差,但噴丸后的TC4鈦合金依然呈現(xiàn)出較好的韌性。
[Abstract]:Titanium alloy is a common metal material in marine and aerospace engineering. At present, surface modification is often used to improve the surface mechanical properties. Laser shot peening is a new technology which uses laser shock wave effect to introduce residual compressive stress into the surface of alloy to achieve surface modification. It has the advantages of better strengthening effect, better controllability and more flexible processing. In this paper, laser shot peening and electrolytic hydrogen charging experiments were carried out on typical TC4 titanium alloy. The effects of laser shot peening on the microhardness, microstructure, tensile mechanical properties and macroscopic microfracture morphology of TC4 titanium alloy before and after hydrogen filling were studied. The anti-hydrogen embrittlement mechanism of laser shot peening TC4 titanium alloy is discussed. The key research contents are as follows: (1) the strengthening mechanism of laser shock wave acting on alloy surface is analyzed theoretically. The microstructure response mechanism of TC4 titanium alloy under the condition of high strain rate and strong plastic deformation was studied. The shot peening path and test parameters of laser shot peening TC4 titanium alloy were established, and the hydrogen diffusion behavior and its influencing factors were revealed. The anti-hydrogen embrittlement mechanism of laser shot peening was discussed. The differences of microstructure and microhardness between shot peening and non-shot peening TC4 titanium alloy before and after electrolytic hydrogen charging were compared. The influence mechanism of laser shot peening on hydrogen permeation was analyzed according to the principle of residual compressive stress distribution in laser shot peening. The results show that laser shot peening induces large residual compressive stress on the surface of TC4 titanium alloy and refines the surface grain of TC4 titanium alloy. The concentration of hydrogen entering the sample decreases with the decrease of grain size in the process of electrolytic hydrogen charging. The hydrogen embrittlement sensitivity of the alloy was decreased, the hardness of the alloy was increased after laser shot peening, the phenomenon of hydrogen induced hardening appeared after electrolytic hydrogen charging, and with the increase of laser power density, the growth rate of hydrogen induced hardening slowed down, and the effect of laser shot peening on hydrogen became smaller. The hydrogen embrittlement resistance of TC4 titanium alloy was improved by laser shot peening. The mechanical properties of TC4 titanium alloy with shot peening and without shot peening were studied by slow tensile test at room temperature before and after electrolytic hydrogen filling. The results showed that laser shot peening increased the tensile strength and elongation of TC4 titanium alloy, and with the increase of laser power density, the tensile strength and elongation also increased, and the tensile strength and elongation of TC4 titanium alloy decreased after electrolytic hydrogen charging. With the increase of laser power density, the hydrogen embrittlement sensitivity of TC4 titanium alloy decreases with the increase of laser power density. By observing the fracture morphology of the sample, it was found that the microfracture was typical dimple morphology, the dimple was deeper, bigger and more uniform after laser shot peening, which showed better toughness, and after electrolytic hydrogen charging, the TC4 titanium alloy without shot peening appeared quasi cleavage fracture. The toughness became worse, but the TC4 titanium alloy still showed good toughness after shot peening.
【學(xué)位授予單位】：江蘇大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TG668;TG146.23

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 張興權(quán);何廣德;汪世益;戚曉利;鄧克;;激光噴丸強(qiáng)化對(duì)調(diào)質(zhì)40Cr鋼組織及耐磨性的影響[J];材料熱處理學(xué)報(bào);2011年05期

2 王金花;激光噴丸強(qiáng)化技術(shù)的應(yīng)用前景[J];材料工程;1999年08期

3 張興權(quán),周建忠,王廣龍,張永康;激光噴丸技術(shù)及其應(yīng)用[J];制造業(yè)自動(dòng)化;2005年10期

4 馬壯;李應(yīng)紅;任旭東;周磊;;航空鋁合金激光噴丸強(qiáng)化研究[J];制造技術(shù)與機(jī)床;2007年10期

5 陳菊芳;李興成;李仁興;申來娣;張永康;;提高金屬抗應(yīng)力腐蝕開裂的激光噴丸技術(shù)[J];激光技術(shù);2011年01期

6 曹子文;鄒世坤;張曉兵;鞏水利;;水約束層在激光噴丸中的應(yīng)用研究[J];應(yīng)用激光;2007年06期

7 周建忠;杜建鈞;黃舒;楊超君;;金屬板料的激光噴丸變形理論[J];材料研究學(xué)報(bào);2007年06期

8 蔣素琴;徐紅光;吳建華;裴旭;;激光噴丸強(qiáng)化變形鎂合金的疲勞壽命數(shù)值分析[J];應(yīng)用激光;2012年05期

9 黃舒;周建忠;陳毅彬;孫月慶;;金屬板料受控激光噴丸強(qiáng)化的殘余應(yīng)力場(chǎng)分析[J];農(nóng)業(yè)機(jī)械學(xué)報(bào);2007年12期

10 李杰;;激光噴丸對(duì)7075鋁合金攪拌摩擦焊接頭的影響[J];宇航材料工藝;2010年01期

相關(guān)會(huì)議論文 前6條

1 范金榮;周建忠;黃舒;王維;樊玉杰;高彬;朱偉;徐增闖;;基于數(shù)值模擬的激光噴丸參數(shù)集成優(yōu)化方法研究[A];中國(guó)光學(xué)學(xué)會(huì)2011年學(xué)術(shù)大會(huì)摘要集[C];2011年

2 李杰;;增強(qiáng)飛機(jī)和航空發(fā)動(dòng)機(jī)零件抗疲勞性能的激光噴丸工藝[A];大型飛機(jī)關(guān)鍵技術(shù)高層論壇暨中國(guó)航空學(xué)會(huì)2007年學(xué)術(shù)年會(huì)論文集[C];2007年

3 吳樹輝;黃科峰;葉林;劉澤坤;尹嵩;;激光噴丸技術(shù)在核電設(shè)備上的應(yīng)用探討[A];中國(guó)核科學(xué)技術(shù)進(jìn)展報(bào)告——中國(guó)核學(xué)會(huì)2009年學(xué)術(shù)年會(huì)論文集（第一卷·第2冊(cè)）[C];2009年

4 朱偉;周建忠;黃舒;樊玉潔;;微尺度激光噴丸純銅數(shù)值模擬和統(tǒng)計(jì)優(yōu)化分析[A];中國(guó)光學(xué)學(xué)會(huì)2011年學(xué)術(shù)大會(huì)摘要集[C];2011年

5 黃舒;周建忠;盛杰;徐增闖;楊晶;左立黨;阮鴻雁;;6061-T6鋁合金激光噴丸后的形變強(qiáng)化及疲勞斷口分析[A];中國(guó)光學(xué)學(xué)會(huì)2011年學(xué)術(shù)大會(huì)摘要集[C];2011年

6 徐增闖;周建忠;黃舒;左立黨;楊晶;;不同激光噴丸覆蓋率下6061-T6鋁合金疲勞裂紋擴(kuò)展的數(shù)值模擬研究[A];中國(guó)光學(xué)學(xué)會(huì)2011年學(xué)術(shù)大會(huì)摘要集[C];2011年

相關(guān)碩士學(xué)位論文 前10條

1 郭峰;激光噴丸對(duì)材料摩擦磨損性能影響的試驗(yàn)研究[D];山東大學(xué);2015年

2 石來民;激光噴丸處理304不銹鋼板應(yīng)力腐蝕試驗(yàn)研究[D];浙江工業(yè)大學(xué);2015年

3 鄭陽(yáng);激光噴丸強(qiáng)化316L不銹鋼抗氫脆性能研究[D];江蘇大學(xué);2016年

4 穆丹;激光噴丸強(qiáng)化醫(yī)用Ti6Al4V合金抗生物腐蝕及腐蝕磨損性能研究[D];江蘇大學(xué);2016年

5 王建軍;激光微造型球墨鑄鐵表面干摩擦性能研究[D];江蘇大學(xué);2017年

6 章海峰;深冷預(yù)處理激光噴丸強(qiáng)化TC6鈦合金殘余應(yīng)力高溫松弛特性研究[D];江蘇大學(xué);2017年

7 徐蘇強(qiáng);深冷預(yù)處理對(duì)2024-T351鋁合金組織性能及激光噴丸強(qiáng)化效果的影響[D];江蘇大學(xué);2017年

8 王祥;激光噴丸強(qiáng)化TC4鈦合金抗氫脆性能及機(jī)理[D];江蘇大學(xué);2017年

9 孫月慶;激光噴丸強(qiáng)化效果的統(tǒng)計(jì)優(yōu)化研究[D];江蘇大學(xué);2008年

10 趙建飛;基于數(shù)值模擬的激光噴丸誘導(dǎo)殘余應(yīng)力場(chǎng)及其疲勞裂紋擴(kuò)展特性研究[D];江蘇大學(xué);2009年

，

本文編號(hào)：1909663