魏亞，付禹，潘志敏，王雪飛，余偉，何石磊，苑清英，駱鴻，李曉剛

腐蝕與防護(hù)

酸性介質(zhì)環(huán)境中溫度對(duì)Ti–Mo合金耐蝕性的影響

魏亞1a，付禹1a，潘志敏1a，王雪飛1a，余偉1b，何石磊2，苑清英2，駱鴻1a，李曉剛1a

（1.北京科技大學(xué) a.新材料技術(shù)研究院 b.工程技術(shù)研究院，北京 100083；2.寶雞石油鋼管有限責(zé)任公司，陜西 寶雞 721008）

研究Ti–Mo合金在不同溫度的20% HCl溶液中的腐蝕行為和腐蝕規(guī)律，并探究其環(huán)境腐蝕機(jī)理。采用X射線(xiàn)衍射儀、掃描電子顯微鏡、電化學(xué)工作站以及X射線(xiàn)光電子能譜等對(duì)Ti–Mo合金的微觀(guān)組織結(jié)構(gòu)和不同介質(zhì)環(huán)境中的耐蝕性進(jìn)行了探究。溶液介質(zhì)溫度對(duì)Ti–Mo合金的腐蝕行為具有顯著影響。當(dāng)溫度從20 ℃上升到70 ℃時(shí)，腐蝕電位從?548.9 mV（vs. Ag/AgCl）降低到?593.3 mV（vs. Ag/AgCl），且腐蝕電流密度在20 ℃時(shí)最低，為36.925 μA/cm2，維鈍電流密度也隨溫度升高而增加。此外，溫度升高不會(huì)改變氧化膜的成分，但會(huì)使膜內(nèi)載流子密度升高，導(dǎo)致氧化膜的半導(dǎo)體特性發(fā)生n–p型轉(zhuǎn)變。當(dāng)溶液溫度為20、30、50、70 ℃時(shí)，腐蝕速率分別為1.138 3、2.931 7、35.217、39.838 6 mm/a，且腐蝕速率隨著溫度升高而增加。溶液溫度升高會(huì)使Ti–Mo合金氧化膜內(nèi)缺陷增多，氧化膜的穩(wěn)定性和耐蝕性降低。在腐蝕過(guò)程中α相與β相會(huì)形成微原電池，α相作為陽(yáng)極更容易發(fā)生優(yōu)先腐蝕，這是由于β相中Mo元素含量較高所致。

Ti–Mo合金；溫度；氧化膜；微原電池

隨著現(xiàn)代工業(yè)體系對(duì)石油需求量的增多，石油管道的安全性也越來(lái)越引起人們的重視[1-2]，管道中的活潑金屬元素易與石油介質(zhì)發(fā)生化學(xué)反應(yīng)，從而導(dǎo)致材料發(fā)生腐蝕失效現(xiàn)象[3]。石油在開(kāi)采和運(yùn)輸過(guò)程中管道常會(huì)受到酸性和Cl?的侵蝕而產(chǎn)生腐蝕，因此現(xiàn)代工業(yè)對(duì)石油管道的耐蝕性提出了很高的要求。通常，服役環(huán)境的pH值越低，材料的腐蝕速率越高。例如氣藏中冷凝水的pH可達(dá)3.5以下，這對(duì)于管道輸送安全是一個(gè)巨大的考驗(yàn)[4-5]。此外，Cl?對(duì)金屬材料表面的保護(hù)膜也有很?chē)?yán)重的破壞作用，而且破壞作用隨著Cl?濃度的升高而增大[6-7]。普通金屬石油管道由于腐蝕原因造成的各種事故給國(guó)民經(jīng)濟(jì)帶來(lái)了極大的損失，因此需要開(kāi)發(fā)新型耐蝕合金來(lái)提高石油管道的服役安全性。

鈦及鈦合金具有密度低[8]、強(qiáng)度高[9]、耐腐蝕性能優(yōu)異[10]特點(diǎn)，在石油化工、航空航天、生物醫(yī)療等領(lǐng)域應(yīng)用廣泛[11]。Ti與O有著很強(qiáng)的親和力，在與O2、H2O相互作用后會(huì)形成亞穩(wěn)態(tài)的Ti(OH)4，由于Ti(OH)4在自然條件下極其不穩(wěn)定，容易分解為T(mén)iO2和H2O，TiO2化學(xué)穩(wěn)定性強(qiáng)。因此，會(huì)在鈦合金基體表面形成一層致密的保護(hù)膜，可以有效阻礙腐蝕介質(zhì)對(duì)基體金屬的侵蝕，達(dá)到保護(hù)鈦合金基體的作用，這是鈦合金耐蝕性?xún)?yōu)異的主要原因[12-13]。目前石油管道運(yùn)輸?shù)慕饘俨牧现饕捎霉芫€(xiàn)鋼，管線(xiàn)鋼在酸性和中性含Cl?溶液中不易形成完整的氧化膜。面對(duì)如此的服役條件，管線(xiàn)鋼容易發(fā)生局部或均勻腐蝕，加速其腐蝕失效[14-15]。相比之下，鈦合金表面形成的TiO2氧化膜更加致密，TiO2氧化膜在較寬的pH范圍內(nèi)都有很高的穩(wěn)定性，極大減少各類(lèi)腐蝕的可能性，而且其表面的氧化膜被破壞后有很強(qiáng)的自修復(fù)能力，所以鈦合金的耐蝕性能也更好[16-17]。因此，鈦合金管道在復(fù)雜石油工況環(huán)境中的服役時(shí)間更長(zhǎng)，效果更好[18]。為了進(jìn)一步提高鈦合金的耐蝕性，學(xué)者們常常在其中添加Mo、Al等元素。研究表明Mo元素能提高鈦合金在Cl?環(huán)境中的耐蝕性，其表面形成的MoO2和MoO3可以作為Cl?向基材運(yùn)動(dòng)的屏障，阻礙腐蝕介質(zhì)對(duì)基體的侵蝕，進(jìn)一步提升鈦合金的耐蝕性[19]。此外，外界服役溫度對(duì)于石油管道腐蝕有很大的影響，溫度升高會(huì)使腐蝕動(dòng)力學(xué)反應(yīng)加速，氧化膜出現(xiàn)溶解，氧化膜破壞之后基材會(huì)直接接觸侵蝕性環(huán)境，造成耐蝕性能下降[20]。

從上述分析可知，研究鈦合金石油管道在嚴(yán)苛環(huán)境下的腐蝕行為和規(guī)律，并探究其腐蝕機(jī)理有非常重大的理論和現(xiàn)實(shí)意義。本文主要探究Ti–Mo合金在不同溫度變化的20% HCl溶液中的腐蝕行為和規(guī)律，旨在揭示Ti–Mo合金的腐蝕機(jī)制，為T(mén)i–Mo合金在石油化工領(lǐng)域的應(yīng)用提供一定的參考價(jià)值。

1 試驗(yàn)

1.1 材料

本試驗(yàn)所用鈦合金（Ti–Mo合金）為寶雞石油鋼管有限責(zé)任公司生產(chǎn)，其主要成分（質(zhì)量分?jǐn)?shù)）為：2.99% Mo，0.60% Zr，0.044% Fe，0.014% C，0.005 1% N，余量為T(mén)i。

1.2 組織觀(guān)察和性能測(cè)試

采用X射線(xiàn)衍射（XRD）對(duì)Ti–Mo合金進(jìn)行物相分析。采用Quanta 250掃描電子顯微鏡（SEM）對(duì)Ti–Mo合金的形貌進(jìn)行觀(guān)察。電化學(xué)測(cè)試采用典型的三電極系統(tǒng)，飽和氯化銀電極為參比電極，對(duì)電極為鉑電極，工作電極為鈦合金試樣，工作電極面積為1 cm2，試驗(yàn)溫度為20～70 ℃。電化學(xué)試驗(yàn)所用儀器為Prin-ceton VersaSTAT 3F 電化學(xué)工作站。為了保證試驗(yàn)結(jié)果的準(zhǔn)確性，樣品在電化學(xué)測(cè)試之前統(tǒng)一在空氣中放置48 h。極化曲線(xiàn)電位范圍為?0.8～2 V（vs. Ag/AgCl），由于掃描范圍較大，掃描速率選取為1 mV/s。電化學(xué)阻抗譜（EIS）的正弦電位擾動(dòng)為10 mV，掃描頻率為10?2～105Hz。采用美國(guó)賽默飛的250Xi X射線(xiàn)光電子能譜儀（XPS）對(duì)氧化膜的化學(xué)組成進(jìn)行研究，成膜電位為0.5 V（vs. Ref），時(shí)間為7 200 s。采用Mott–Schottky對(duì)半導(dǎo)體膜的性質(zhì)進(jìn)行探究，Mott– Schottky試驗(yàn)頻率為1 000 Hz，掃描電位為2～ ?1 V，步長(zhǎng)為20 mV。選擇了20% HCl溶液作為靜態(tài)浸泡測(cè)試溶液，溶液的溫度分別保持在20、30、50、70 ℃。由于Ti–Mo合金在常溫下腐蝕較慢，為了使腐蝕前后的形貌變化更明顯，選取浸泡時(shí)間為15 d。浸泡15 d后用蒸餾水和酒精超聲清洗，干燥后用精度為±0.1 mg的天平稱(chēng)量，并用3D共聚焦和掃描電子顯微鏡觀(guān)察腐蝕后的形貌。

2 結(jié)果與討論

2.1 鈦合金原始樣品組織結(jié)構(gòu)分析

如圖1的Ti–Mo合金的XRD圖譜所示，鈦合金原始樣品主要由α相和β相組成，是典型的雙相結(jié)構(gòu)。圖2為鈦合金原始樣品微觀(guān)結(jié)構(gòu)和元素分布，圖中α相和β相相間分布。EDS結(jié)果顯示，基體Ti元素的整體分布比較均勻，Mo元素和Zr元素主要富集在β相中，在α相中含量較少。

圖1 Ti–Mo合金樣品的XRD圖譜

2.2 電化學(xué)分析

2.2.1 開(kāi)路電位和極化曲線(xiàn)

圖3a為T(mén)i–Mo合金在不同溫度條件下20% HCl溶液中的開(kāi)路電位變化曲線(xiàn)。開(kāi)路電位的下降對(duì)應(yīng)著鈦合金表面自然氧化膜的溶解，溫度升高使表面氧化膜的溶解速度逐漸加快。圖3b所示的陰極區(qū)主要為析氫反應(yīng)[21-22]，陽(yáng)極區(qū)由活化溶解區(qū)、活化鈍化過(guò)渡區(qū)、一次鈍化區(qū)、二次鈍化區(qū)和過(guò)鈍化區(qū)5種區(qū)域組成。活化溶解區(qū)內(nèi)鈦基體被氧化成可溶的Ti3+并進(jìn)入到溶液中，電流密度逐漸增大。當(dāng)活化溶解區(qū)的陽(yáng)極電流達(dá)到最大，表明活化鈍化過(guò)渡區(qū)的開(kāi)始，此區(qū)域內(nèi)TiO2氧化膜生成，電流密度開(kāi)始減小?；罨g化過(guò)渡區(qū)之后，在?0.2～1.2 V之間出現(xiàn)了明顯的鈍化區(qū)，20、30 ℃時(shí)鈍化區(qū)內(nèi)的電流密度基本保持不變，50、70 ℃時(shí)區(qū)域內(nèi)的電流密度出現(xiàn)了波動(dòng)，發(fā)生了亞穩(wěn)態(tài)點(diǎn)蝕，此區(qū)域內(nèi)的電流密度波動(dòng)是由氧化膜的溶解和生成的競(jìng)爭(zhēng)作用所致，在發(fā)生亞穩(wěn)態(tài)點(diǎn)蝕之后電流密度又逐漸減小，說(shuō)明氧化膜重新生成，表明Ti–Mo合金有很好的自修復(fù)能力[23]。在1.2～1.6 V內(nèi)出現(xiàn)了二次鈍化區(qū)，二次鈍化區(qū)的形成是氧化膜的溶解和競(jìng)爭(zhēng)重新達(dá)到平衡所致。當(dāng)電壓大于1.6 V后出現(xiàn)了過(guò)鈍化現(xiàn)象，此時(shí)鈍化膜的溶解速度加快，電流密度加速增大。采用Tafel外推法從動(dòng)電位極化曲線(xiàn)得到corr和corr值見(jiàn)表1。結(jié)果顯示，Ti–Mo合金在20 ℃時(shí)的腐蝕電位corr最高（?554.889 V），同時(shí)腐蝕電流密度corr也最低（36.925 μA/cm2），20 ℃時(shí)耐蝕性最好。維鈍電流密度能夠較好地反映鈍化膜的環(huán)境穩(wěn)定性，在極化曲線(xiàn)的鈍化區(qū)內(nèi)，選取0.5 V對(duì)應(yīng)的電流密度為維鈍電流密度（pass），維鈍電流密度隨溫度升高逐漸增大，表明耐腐蝕性能隨溫度升高逐漸下降。

圖3 Ti–Mo合金在20～70 ℃的20% HCl溶液中的開(kāi)路電位和極化曲線(xiàn)

表1 由動(dòng)電位極化曲線(xiàn)推導(dǎo)出的參數(shù)

Tab.1 Parameters derived from the potentiodynamic polarization curve

2.2.2 電化學(xué)阻抗譜（EIS）分析

為了進(jìn)一步闡明介質(zhì)溫度變化對(duì)Ti–Mo合金腐蝕性能的影響，在20% HCl溶液中進(jìn)行EIS測(cè)試，相應(yīng)的Nyquist和Bode圖如圖4所示。圖4a的Nyquist圖出現(xiàn)2個(gè)容抗弧，表明存在2個(gè)時(shí)間常數(shù)。高頻電容回路對(duì)應(yīng)于電解液與Ti–Mo合金基體界面處的雙電層，低頻電容回路對(duì)應(yīng)于表面的氧化膜。高頻電容回路半徑減小說(shuō)明電荷轉(zhuǎn)移電阻減小，低頻電容回路半徑減小表明表面膜電阻減小。圖4b是在20% HCl溶液中測(cè)量的Bode圖，Bode圖中相位角隨著溶液溫度的升高逐漸減小，相位角越大表明氧化膜越致密，在70 ℃時(shí)相位角接近30°表明形成的氧化膜已經(jīng)非常不致密[24-25]。

采用圖5所示的等效電路對(duì)阻抗譜進(jìn)行擬合，在等效電路中，S是溶液電阻，1和ct分別是與雙電層電容和電荷轉(zhuǎn)移電阻有關(guān)的元件，2和f分別是與氧化物/腐蝕產(chǎn)物膜電容和氧化物/腐蝕產(chǎn)物膜電阻有關(guān)的元件[26]。擬合的電化學(xué)阻抗譜數(shù)據(jù)如表2所示，極化電阻（p）可以用來(lái)評(píng)估耐蝕性[27]，其中p=f+ct。經(jīng)過(guò)計(jì)算，20、30、50、70 ℃時(shí)，Ti–Mo合金在20% HCl溶液中的極化電阻分別為314.20、111.29、27.29、8.76 ?·cm2。極化電阻隨著溶液溫度的升高逐漸減小，Ti–Mo合金的耐蝕性逐漸變差。

圖4 Ti–Mo合金在20～70 ℃的20% HCl溶液中的阻抗譜

圖5 Ti–Mo合金在20% HCl溶液中阻抗譜的等效電路圖

2.3 XPS分析

Ti–Mo合金的耐蝕性與表面氧化膜的成分密切相關(guān)，因此采用XPS對(duì)Ti–Mo合金在溶液中形成的氧化膜的成分進(jìn)行分析。從圖6所示的XPS全譜中，可以看到O 1s、Ti 2p、C 1s、Mo 3d、Zr 3d的存在，其中C 1s的存在是由于檢測(cè)過(guò)程中引入的污染物C。

Ti 2p的擬合圖譜如圖7所示，458.7 eV的峰位可以擬合成雙峰，分別對(duì)應(yīng)于459.1 eV的TiO2和457.0 eV的Ti2O3，453.8 eV的峰位對(duì)應(yīng)于金屬Ti[28]。圖8所示的O1s的峰位也可擬合成3種物質(zhì)，分別是530.4 eV的O2?、532.3 eV的OH?和533.0 eV的 O2?(H2O)[29]。從圖9a可以看到，Mo 3d在229.1 ev和232.2 eV處有2個(gè)明顯的峰位，分別對(duì)應(yīng)于 MoO2和 MoO3氧化物[30]。Zr 3d在182.4 ev和184.1 eV處也有ZrO2峰的出現(xiàn)，但峰位較弱，表明含量較少[31]。通過(guò)對(duì)擬合的Ti 2p峰進(jìn)行計(jì)算可知，20、30、50、70 ℃下，氧化膜中TiO2的占比分別為81.9%、88.8%、78.8%和84.2%，Ti2O3的占比分別為13.0%、8.2%、13.6%和11.6%，Ti的占比分別為5.1%、3.0%、7.6%和4.2%，對(duì)比各相的比例得不出明顯規(guī)律。通過(guò)XPS分析可知氧化膜的成分由鈦合金的氧化物、氫氧化物以及Mo和Zr的氧化物組成。但XPS不能獲得氧化膜的半導(dǎo)體特性和膜內(nèi)載流子密度，所以采用Mott–Schottky測(cè)試?yán)^續(xù)分析合金表面氧化膜的特性。

表2 Ti–Mo合金在20% HCl溶液中的電化學(xué)阻抗譜擬合參數(shù)

Tab.2 Fitting parameters of Ti-Mo alloy in 20wt.% HCl solution

圖6 Ti–Mo合金在不同溫度的20% HCl溶液中表面氧化膜的全譜圖

圖7 XPS結(jié)果中的Ti 2p峰擬合圖

圖8 XPS結(jié)果中的O 1s峰擬合圖

圖9 XPS結(jié)果中的Mo 3d峰和Zr 3d峰

圖10 Ti–Mo合金在20～70 ℃的20% HCl溶液中的Mott–Schottky結(jié)果

表3 由Mott–Schottky曲線(xiàn)擬合得到的載流子密度和平帶電位

Tab.3 ND/A and flat-band potential derived from Mott-Schottky in 20wt.% HCl solution

2.4 靜態(tài)浸泡試驗(yàn)

由圖11a可知，Ti–Mo鈦合金的單位面積失重從20 ℃的21.051 2 mg/cm2增加到70 ℃的736.742 2 mg/cm2。采用公式（3）對(duì)鈦合金的腐蝕速率做出了直觀(guān)的計(jì)算，式中代表鈦合金腐蝕速率（mm/a），1是鈦合金腐蝕前質(zhì)量（g），2是鈦合金腐蝕后質(zhì)量（g），代表鈦合金試樣表面積，代表試驗(yàn)時(shí)間（h），代表鈦合金密度（4.5 g/cm3）[37]，經(jīng)過(guò)計(jì)算得到20、30、50、70 ℃時(shí)，腐蝕速率分別為1.138 3、2.931 7、35.217 4、39.838 6 mm/a。

圖12a—d為腐蝕后樣品的3D共聚焦表面形貌及沿圖中白線(xiàn)分布的腐蝕坑深度。從圖12的3D共聚焦顯微鏡的結(jié)果可以看出，浸泡后樣品表面的溝壑逐漸增多，70 ℃甚至出現(xiàn)了開(kāi)裂現(xiàn)象。3D共聚焦結(jié)果顯示，20、30、50、70 ℃時(shí)，最大腐蝕深度依次為12.426、13.601、23.957、41.492 μm。圖13為T(mén)i–Mo合金浸泡15 d之后的腐蝕形貌，可以看到Ti–Mo合金已經(jīng)嚴(yán)重腐蝕，說(shuō)明此時(shí)的氧化膜已經(jīng)破裂。圖13a為20 ℃浸泡15 d后的腐蝕形貌，Ti–Mo合金呈現(xiàn)出典型的不均勻腐蝕，α相腐蝕較為嚴(yán)重并出現(xiàn)了尖銳的棱角，β相腐蝕程度相對(duì)較輕，在浸泡過(guò)程中α相和β相會(huì)形成微原電池，這是因?yàn)棣孪嘀蠱o含量較高，在腐蝕過(guò)程中作為陰極，α相作為陽(yáng)極會(huì)加速腐蝕[38]。當(dāng)溫度升高至30 ℃時(shí)，可以清楚看到α相與β相交錯(cuò)分布，此時(shí)β相形狀為細(xì)條狀，相比20 ℃時(shí)腐蝕進(jìn)一步加劇。50 ℃浸泡15 d后可以看到α相已無(wú)尖銳棱角，70 ℃浸泡15 d后樣品已經(jīng)明顯疏松，腐蝕逐步加重。浸泡結(jié)果與之前的電化學(xué)測(cè)試結(jié)果保持一致。

圖12 Ti–Mo合金在20～70 ℃的20% HCl溶液中浸泡15 d的3D共聚焦形貌

圖13 Ti–Mo合金在20% HCl溶液浸泡15 d后腐蝕形貌

3 結(jié)論

1）電化學(xué)測(cè)試結(jié)果顯示，溶液介質(zhì)溫度會(huì)使得Ti–Mo合金的腐蝕電流密度和維鈍電流密度增加，同時(shí)減小電荷轉(zhuǎn)移電阻和膜電阻。

2）結(jié)合XPS和Mott–Schottky分析結(jié)果可知，溶液介質(zhì)溫度升高會(huì)造成Ti–Mo合金表面氧化膜內(nèi)的缺陷增多，氧化膜半導(dǎo)體類(lèi)型會(huì)發(fā)生轉(zhuǎn)變。

3）浸泡結(jié)果顯示，Ti–Mo合金的腐蝕速率和腐蝕坑深度都隨著溶液溫度升高而增大。在浸泡過(guò)程中α相和β相會(huì)形成微原電池，β相中Mo含量較高，在腐蝕過(guò)程中作為陰極，α相作為陽(yáng)極，兩相耦合會(huì)加速鈦合金的腐蝕。

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The Influence of Temperature on Corrosion Resistance of Ti-Mo Alloy in Acidic Medium

1a,1a,1a,1a,1b,2,2,1a,1a

(1. a. Institute for Advanced Materials and Technology, b. Institute of Engineering and Technology, University of Science and Technology Beijing, Beijing 100083, China; 2. CNPC Baoji Petroleum Steel Pipe Co., Ltd., Shaanxi Baoji 721008, China)

Titanium alloy pipeline is playing an increasingly important role in petrochemical industry. This paper mainly explores the corrosion behavior of Ti-Mo alloy in 20wt.% HCl solution with different temperature changes, aiming at revealing the corrosion mechanism of Ti-Mo alloy and providing certain reference value for the application of Ti-Mo alloy in petrochemical industry.

The titanium alloy used in this experiment is produced by CNPC Baoji Petroleum Steel Pipe Co., Ltd. The main components (wt.%) are as follows: 2.99 Mo, 0.60 Zr, 0.044 Fe, 0.014 C, 0.005 1 N, and the balance is Ti. X-ray diffraction (XRD) and Quanta 250 scanning electron microscope (SEM) were used to observe the phase and morphology of Ti-Mo alloy. Electrochemical test adopts typical three-electrode system, with saturated silver chloride electrode as reference electrode, platinum electrode as counter electrode, titanium alloy sample as working electrode with the area of 1 cm2. The electrochemical experiment temperature were 20, 30 50 and 70 ℃. The potential range of polarization curve was ?0.8 V (vs. Ag/AgCl) to 2 V (vs. Ag/AgCl) and the scanning frequency of electrochemical impedance spectroscopy (EIS) was 10?2Hz to 105Hz. The chemical composition of the oxide film was studied by 250Xi X-ray photoelectron spectroscopy. The oxide film was formed at 0.5 V (vs. Ref) for 7 200 s. Mott-Schottky was used to explore the properties of semiconductor films. The experimental frequency of Mott-Schottky was 1 000 Hz, the scanning potential was 2 to ?1 V with the step size of 20 mV. 20wt.% HCl solution was selected as the static immersion test solution, and the temperature of the solution was kept at 20 ℃, 30 ℃, 50 ℃ and 70 ℃ respectively. After soaking for 15 days, ultrasonic cleaning with distilled water and alcohol, drying, weighing with a balance with accuracy of 0.1 mg, and observing the morphology after corrosion with 3D laser confocal and scanning electron microscope.

The solution medium temperature produced a great influence on the corrosion behavior of Ti-Mo alloy. The corrosion potential decreased from ?548.9 mV (vs. Ag/AgCl) to ?593.3 mV (vs. Ag/AgCl) in the range of 20 to 70 ℃. Ti-Mo alloys had the lowest corrosion current density at 20 ℃, i. e., 36.925 μA/cm2, and the passive current density decreased as the temperature enhanced. In addition, the content of the oxide film had no obvious difference at various temperature, but the donor concentration in the film increased at elevated temperature. Besides, it caused the n-p type transition of the semiconductor characteristics. The corrosion rate of the Ti-Mo alloy in 20wt.% HCl solution were 1.138 3, 2.931 7, 35.217 and 39.838 6 mm/a when solution temperature were 20, 30, 50 and 70 ℃, which indicated that the corrosion rate accelerated with the temperature went by.

An increase in the temperature of the solution will promote the formation of defects and reduce the stability and corrosion resistance of the oxide film. The α and β phases form microgalvanic cells in the corrosion process, and the α phase is more prone to corrode acting as the anode, which is due to the higher content of Mo in the β phase.

Ti-Mo alloy; temperature; oxide film; microgalvanic cells

2021-07-09；

2022-01-25

WEI Ya (1995-), Male, Postgraduate, Research focus: titanium alloy corrosion and protection.

駱鴻（1980—），男，博士，教授，主要研究方向?yàn)橄冗M(jìn)金屬、鋼鐵材料的設(shè)計(jì)和服役安全。

LUO Hong (1980-), Male, Doctor, Professor, Research focus: design and service safety of advanced metal and steel materials.

魏亞, 付禹, 潘志敏, 等.酸性介質(zhì)環(huán)境中溫度對(duì)Ti–Mo合金耐蝕性的影響[J]. 表面技術(shù), 2022, 51(9): 168-177.

tg174

A

1001-3660(2022)09-0168-10

10.16490/j.cnki.issn.1001-3660.2022.09.000

2021–07–09；

2022–01–25

中國(guó)石油科技創(chuàng)新基金（2019D–5007–0308）；國(guó)家重點(diǎn)研究開(kāi)發(fā)項(xiàng)目（2016YFB0301204）；中央高?；究蒲袠I(yè)務(wù)基金（FRF– MP–20–51，F(xiàn)RF–BD–20–28A2）

Fund：PetroChina Innovation Foundation (2019D-5007-0308); National Key Research and Development Program of China (2016YFB0301204); Fundamental Research Funds for the Central Universities (FRF-MP-20-51, FRF-BD-20-28A2)

魏亞（1995—），男，碩士研究生，主要研究方向?yàn)殁伜辖鸶g與防護(hù)。

WEI Ya, FU Yu, PAN Zhi-min, et al. The Influence of Temperature on Corrosion Resistance of Ti-Mo Alloy in Acidic Mediu[J]. Surface Technology, 2022, 51(9): 168-177.

責(zé)任編輯：萬(wàn)長(zhǎng)清