(1. 東北石油大學(xué) 機(jī)械科學(xué)與工程學(xué)院，大慶 163318；
2. 大慶油田有限責(zé)任公司 建設(shè)集團(tuán)，大慶 163159；
3. 中國(guó)石油集團(tuán)長(zhǎng)城鉆探工程有限公司 工程技術(shù)研究院，盤津 124010)
摘 要: 基于第一性原理計(jì)算法，采用CASTEP模塊計(jì)算稀土Ce摻雜Cr13鋼的吸附能，分析稀土Ce對(duì)Cr13鋼耐CO2腐蝕性能的微觀影響機(jī)制。通過(guò)等離子電弧爐制備添加不同含量Ce元素的Cr13鋼，測(cè)試合金的顯微組織及其在含飽和CO2的3.5%(質(zhì)量分?jǐn)?shù))NaCl液中的腐蝕電化學(xué)行為。結(jié)果表明：Cr13鋼摻雜稀土Ce后，吸附結(jié)構(gòu)的穩(wěn)定性減小，Ce含量為0.1%(質(zhì)量分?jǐn)?shù))時(shí)，吸附結(jié)構(gòu)的穩(wěn)定性最小。適量稀土Ce添加可細(xì)化基體鐵素體晶粒、減小碳化物的數(shù)量及偏聚。稀土Ce摻雜Cr13鋼在含飽和CO2介質(zhì)中呈現(xiàn)出明顯的鈍化行為，Ce的添加量與鈍化穩(wěn)定性間存在臨界值，當(dāng)稀土Ce添加量為0.1%時(shí)，鈍化電流密度最小、鈍化區(qū)間最寬，具有最優(yōu)的抗CO2腐蝕性能。第一性原理計(jì)算方法在預(yù)見材料耐CO2腐蝕性能方面具有很強(qiáng)的可靠性，對(duì)設(shè)計(jì)耐蝕材料具有較強(qiáng)的指導(dǎo)意義。
關(guān)鍵字: 第一性原理；Cr13鋼；稀土元素；抗腐蝕性能
（1. School of Mechanical Science and Engineering, Northeast Petroleum University, Daqing 163318, China;
2. Construction Group, Daqing Oilfield Co., Ltd, Daqing 163159, China;
3. Engineering and Technology Research Institute,
China National Petroleum Corporation Greatwall Drilling Company, Panjin 124010, China）
Abstract:The adsorption energy of Ce doped Cr13 steel was calculated by CASTEP module based on the first principle method. The effects of Ce on the CO2 corrosion resistance of Cr13 steel were analyzed. The Cr13 steel doped different Ce contents was prepared by plasma arc furnace. The microstructure and electrochemical corrosion behavior of prepared alloys in the 3.5% (mass fraction) NaCl solution saturated with CO2 were investigated. The results indicate that the stability of adsorption structure reaches to a minimum value when the content of Ce is 0.1% (mass fraction). The adsorption quantity of Ce can refine the Fe grain and reduce the amount of carbide, leading to little segregation of alloy elements. Ce doped Cr13 alloys exhibits the remarkable passivation behavior. When the content of Ce is 0.1% (mass fraction), the passivation current density is the lowest and the passivation region is the widest, and the alloy exhibits the enhanced CO2 corrosion resistance. The first principles method shows a promising application in forecasting CO2 corrosion and has much directive meaning in designing new ant-corrosion materials.
Key words: first-principles calculations; Cr13 steel; rare earth element; corrosion resistance
