碳钢在含沙油田水中腐蚀-磨损交互作用研究

用自制的旋转试片摩擦电化学装置，参照油气生产过程，研究含沙油水田中碳钢的腐蚀－磨损．试验结果发现，交互作用强度很大，并在适中腐蚀性和磨损条件时处于极值．本研究条件下交互作用和纯腐蚀的两者对数值呈良好线性关系．

含沙多相流对金属管道腐蚀-磨损及其监测

根据近年资料 ,系统介绍了含固体颗粒和沙的流体对金属管道腐蚀 -磨损的计算公式和检测技术。讨论了API - 14E公式、Salama修正公式、Lots方程等磨损预测模型 ,分析了主要影响因素 ,重点介绍抗磨损阻力ECR和临界流速等判别指标 ,包括其意义、测量和计算方法、判别准则和具体应用。此外还介绍目前流行的沙磨损监测技术 :(1)检测磨损量的电阻式传感器 ,传感器结构原理、相关计算公式及具体检测方法 ;(2 )检测沙量的声波检测器 ,它们的测量原理和具体应用方法等。

摩擦-电化学噪声法研究Mo改性钛合金的腐蚀-磨损行为

利用等离子表面改性技术在Ti6Al4V合金基体上制备Mo渗镀复合改性层,考察改性层组织结构,利用微动摩擦学试验机并结合电化学噪声技术对比研究基材及改性层在0.5 mol/L NaCl溶液中的腐蚀-微动摩擦学行为,对腐蚀-摩擦过程中的噪声参数进行分析.结果表明:纯Mo改性层能够明显改善钛合金的耐磨和减摩特性;同时提高了合金在0.5 mol/L NaCl溶液中的自腐蚀电位及降低了腐蚀电流,改善了合金表面的腐蚀-摩擦学性能.

新型高温金属腐蚀-磨损试验机及其应用

为研究材料在熔融金属中的腐蚀-磨损机理,自行研制了一种新型高温金属腐蚀-磨损试验机,其主要技术参数为:环-块式摩擦磨损试验;旋转主轴转速为0～150r/min,无级可调;砝码加载,加载范围为0～200N;摩擦力测量范围为0～100N;试验温度为室温～1000℃;电炉控温精度为±1℃。利用该试验机,对H13钢在铝液中的腐蚀-磨损性能进行了测试。结果表明,该试验机可以模拟材料在熔融金属中同时承受腐蚀和磨损的行为,测量材料的摩擦因数曲线和腐蚀-磨损量,试验过程平稳。

超音速火焰喷涂Cr_3C_2-NiCr涂层腐蚀冲蚀磨损特性

在腐蚀冲蚀磨损试验机上,用5%H2SO4和质量分数15%棕刚玉组成的腐蚀-冲蚀磨损介质,对不同燃气流量下HVOF喷涂Cr3C2-25%NiCr涂层腐蚀冲蚀磨损性能进行了试验研究,测定了涂层单位面积失重量随腐蚀冲蚀磨损时间和冲蚀角度的变化,用扫描电镜观察了涂层断面组织形貌,分析了涂层腐蚀冲蚀磨损机制.研究表明,涂层的腐蚀冲蚀磨损累积失重量随时间基本呈线性增加,适中燃气流量所沉积涂层的腐蚀冲蚀磨损率较低,且远低于低碳钢.涂层的腐蚀冲蚀磨损主要表现为早期腐蚀介质对粘结相的优先冲蚀腐蚀和随后碳化物颗粒剥落以及涂层沿层间的裂纹扩展、相互贯通和扁平粒子脱落.

新型极地船用钢在模拟低温海水中的磨损-腐蚀耦合作用研究

分别采用正火和调质工艺对新型破冰船用低碳高强钢进行了热处理,并使用UMT-3多功能摩擦磨损试验机低温模块和摩擦电化学模块研究了其在低温模拟海水环境中不同外加电位下的磨损-腐蚀耦合行为.使用电子扫描显微镜和白光干涉显微镜对钢样的微观组织及磨痕形貌进行了表征,并对其在不同外加电位作用下的磨损-腐蚀机理进行了探讨.结果表明:两种热处理后的钢材的平均摩擦系数都随外加电位升高而降低,而磨痕深度、磨损量和腐蚀电流则随着外加电位升高而增加;钢材的开路电位随着磨损的发生逐渐负移,腐蚀电流密度增加;其中,经过正火处理的钢样磨痕表面主要出现剥落坑,而调质钢磨痕表面则主要出现了裂纹和腐蚀坑.正火钢磨损和腐蚀损失量所占比例分别为80.6%、19.4%,调质钢分别为55.1%、44.9%,两种钢材的磨损-腐蚀之间相互促进损失量ΔVW和ΔVC均为正值,证实磨损和腐蚀之间存在着相互协同作用.

Hank's模拟体液中医用TLM合金的微磨粒磨损行为

采用TE66微磨粒磨损实验机对外科植入材料Ti-Zr-Nb-Mo-Sn(TLM)钛合金在Hank's模拟人体体液中的微磨粒磨损行为进行研究。通过正交实验结果可知:影响TLM钛合金微磨粒磨损行为的各因素的显著程度由高到低依次为料浆浓度、载荷、滑移速度、磨粒及滑移距离,并研究料浆浓度对TLM钛合金微磨损行为的影响。结果表明:不同载荷下,由于单位体积内的磨粒数量增加致使TLM钛合金的磨损体积随料浆浓度增加而增加;摩擦因数在微磨损-腐蚀共同作用下随料浆浓度增加先增加而后降低,主要是由于随着微磨损-腐蚀的进行,在摩擦副表面产生氧化膜或钝化膜,而这些膜具有一定的润滑作用致使摩擦因数降低;同时可得知在浓度相同时,载荷越大,摩擦因数越大。

Review on corrosion-wear resistance performance of materials in molten aluminum and its alloys

The failure caused by the corrosion-wear of molten aluminum and its alloys is one of the main problems in aluminum industry. In this work, the resistance behavior of various materials, including Fe-based alloys, ceramics and corresponding high apparatus of corrosion-wear in molten aluminum and its alloys, were reviewed. The synergistic effect of corrosion and wear was discussed based on corrosion and wear mechanics. The effects of dynamic agitation due to rotating of friction pairs, physical property of liquid metal and size of grain etc., on the corrosion-wear resistance performance were investigated. In addition, the characteristics of corrosion-wear resistance performance of materials in molten aluminum and its alloy were summarized. According to our recent progress referred to kinds of materials, especially a TiA13/Ti3A1C2/A1203 composite, the ceramics/metal composites with a co-continuous structure will be of great advantage in the field of corrosion-wear environment of molten aluminum and its alloys.

Tribocorrosion behaviors of Ti-6Al-4V and Monel K500 alloys sliding against 316 stainless steel in artificial seawater

The tribocorrosion behaviors of Ti-6Al-4V and Monel K500 alloys sliding against 316 stainless steel were investigated using a ring-on-block test rig in both artificial seawater and distilled water. It is found that friction coefficients are in general larger in distilled water compared with seawater. The wear losses of Ti-6Al-4V and Monel K500 alloys are larger in seawater compared with distilled water. The mechanical action can destroy the passive film and increase the corrosion rate. The synergism effect between corrosion and wear occurs. The synergism action between corrosion and wear is related to the corrosion rate and with the increase of corrosion rate, the synergism becomes more important. 316 stainless steel suffers severe wear sliding against Monel K500 alloy compared with sliding against Ti-6Al-4V alloy in both distilled water and seawater.

Effect of electrochemical state on corrosion-wear behaviors of TC4 alloy in artificial seawater

The electrochemical and corrosion?wear behaviors of TC4 alloy in artificial seawater were studied. And the influences of electrochemical state on passive behavior, failure mechanism of passive film and corrosion?wear synergy were emphatically analyzed. The corrosion?wear analysis of the alloy was fulfilled by methods of mass loss, electrochemical testing and scanning electron microscope (SEM). It can be observed that the cathodic shift of open circuit potential and three order of magnitude increase of current density can be obtained during corrosion?wear process. Total corrosion?wear loss increases with increasing applied potential, confirming the synergy between wear and corrosion. High polarisation potential results in low coefficient of friction and high corrosion rate. The relative contribution of pure mechanical wear to total material loss deceases obviously with the increase of potential from open circuit potential to 0.9 V during corrosion?wear. Contributions of wear-induced-corrosion and corrosion-induced-wear are significant especially at higher potentials.

润滑耐磨耐蚀功能一体化有机黏结涂层的研究进展

随着现代化装备技术的快速发展,高端机械装备服役工况变得愈加复杂苛刻,磨损与腐蚀耦合损伤加速了高端机械装备运动部件的损伤失效,导致装备服役寿命大幅缩减,带来了严重的安全问题。润滑耐磨耐蚀功能一体化有机黏结涂层克服了润滑耐磨涂层和防腐蚀涂层的单一功能局限,为解决运动部件的磨损和腐蚀问题提供了有效方案。文中首先探讨了关键运动部件面临复杂服役工况的严峻挑战、材料磨损与腐蚀耦合的损伤机制;然后分别由黏结剂、填料和润滑剂3个方面介绍了目前润滑耐磨耐蚀功能一体化有机黏结涂层的研究进展,对涂层的组成结构与力学性能、摩擦学性能、耐腐蚀性能间的构效关系进行了分析,并对不同涂层的局限性进行了概述;之后详细总结了润滑耐磨耐蚀功能一体化涂层的应用现状;最后对润滑耐磨耐蚀功能一体化涂层的发展方向进行展望。

Corrosion and wear properties of micro-arc oxidation treated Ti6Al4V alloy prepared by selective electron beam melting

In order to analyze the effect of voltage during micro-arc oxidation(MAO)on corrosion and wear properties of Ti6Al4V(TC4),the MAO technology was employed to treat TC4 samples fabricated by selective electron beam melting(SEBM)at the voltages of 400,420 and 450 V.The results show that the metastable anatase phase gradually transforms to rutile phase with oxidation time and temperature increasing.The surface morphology of coating contains numerous micropores with uniform size distribution.Cracks and pores over 10μm are found on MAO-TC4 sample with applied voltage of 450 V.The thickness of MAO coating is positively correlated with the voltage.The corrosion resistance and wear resistance are related to phase composition,micropore size distribution on the surface and film thickness.When the voltage is 420 V,the coating shows the smallest corrosion current density(0.960×10^-7 A/cm^2)and the largest resistance(7.17×10^5Ω·cm^2).Under the same load condition,the coating exhibits larger friction coefficient and wear loss than the TC4 substrate.With the increase of voltage,the wear mechanism of the coating changes from abrasive wear to adhesive wear,and the adhesive wear is intensified at applied voltage of 450 V,with a maximum friction coefficient of 0.821.

Wear and corrosion resistance and electroplating characteristics of electrodeposited Cr-SiC nano-composite coatings

Cr-SiC nanocomposite coatings with various contents of SiC nanoparticles were prepared by electrodeposition in optimized Cr plating bath containing different concentrations of SiC nanoparticles. Direct current electrocodeposition technique was used to deposit chromium layers with and without SiC nanoparticles on mild carbon steel. The effects of current density, stirring rate and concentration of nanoparticles in the plating bath were investigated. Scanning electron microscopy was used to study surface morphology. Energy dispersive analysis technique was used to verify the presence of SiC nanoparticles in the coated layers. The corrosion behaviors of coatings were investigated by potentiodynamic polarization and electrochemical impedance spectroscopy methods in 0.05 mol/L HCl, 1 mol/L NaOH and 3.5% NaCl （mass fraction）, respectively. Microhardness measurements and pin-on- disc tribometer technique were used to investigate the wear behavior of the coatings.

Wear and corrosion behavior of clay containing coating on AM 50 magnesium alloy produced by aluminate-based plasma electrolytic oxidation

This study aims to examine the effect of clay micro particles addition on the microstructure,wear and corrosion behavior of PEO coatings on AM 50 magnesium alloy.PEO coatings were prepared using an aluminate-based electrolyte with and without the presence of 5 g/L clay particles.The structure and composition of the coatings were evaluated using SEM,EDS and XRD.The wear investigations were conducted using a ball-on-disk tribometer at 2,5 and 10 N loads.The corrosion behavior of the coatings was examined using polarization and EIS tests in 0.5 wt.%NaCl.The results revealed that the addition of clay particles deteriorated the wear resistance of the coatings under the loads of 5 and 10 N.The SEM examinations of the worn surfaces indicated that a combination of adhesive and abrasive wear mechanisms was activated for the coating with clay particles.The poor wear performance of the clay-incorporated coating was related to its lower adhesion strength and higher roughness.The potentiodynamic polarization examinations revealed that the addition of clay particles slightly decreased the corrosion rate of the coatings.Corrosion resistance of the clay-containing coating was attributed to its compactness,as indicated by the results of EIS tests.

Fabrication of Co-Ni-P film with excellent wear and corrosion resistance by electroplating with supercritical CO_2 emulsion

To avoid the defects caused by the hydrogen evolution and improve the corrosion and wear properties of the electroplated films in the traditional aqueous bath electrodeposition,a supercritical carbon dioxide(Sc-CO2)emulsion was proposed to electrodeposite ternary nanocrystalline Co-Ni-P alloy films.Microstructure,corrosive and tribological properties of the Co-Ni-P films were investigated and compared with the ones electroplated by conventional method.The results show that the Co-Ni-P films produced with Sc-CO2assisted electrodeposition exhibit a more compact microstructure.The preferred orientation plane of hcp(110)for the Co-Ni-P films produced in conventional aqueous bath is changed to be hcp(100)for the one prepared in emulsified Sc-CO2bath.The microhardness,corrosion resistance and tribological properties of the Co-Ni-P films are substantially improved with the assistance of Sc-CO2in the electrodeposition bath.

Effects of T6 heat treatment on mechanical, abrasive and erosive-corrosive wear properties of eutectic Al-Si alloy

The abrasive and erosive-corrosive properties of eutectic Al-Si （LM6） alloy were studied. Microstructural features of the alloy were altered by controlling the T6 heat treatment parameter, and their influence on hardness, strength and elongation, and response of the samples in erosion-corrosion and abrasion conditions were studied. Characteristics of the Al-Si alloy samples were compared with those of Al conventionally used in agricultural machineries. Fabrication of a typical component using the Al-Si alloy was also explored in order to understand the feasibility of using the alloy system for the envisaged applications. The study suggests the response of the samples in different conditions to be greatly influenced by parameters like chemical composition, microstructural features and applied load, traversal distance and test environment. The performance of even the as cast Al-Si alloy is far superior to that of the conventional Al samples, while the T6 heat treated Al-Si alloy shows improved performance. Accordingly, the as-cast as well as T6 heat treated Al-Si alloy has potential for applications in agriculture as a replacement for the conventionally used Al.

Effects of titanium addition on structural, mechanical, tribological, and corrosion properties of Al-25Zn-3Cu and Al-25Zn-3Cu-3Si alloys

To investigate the effect of grain refinement on the material properties of recently developed Al-25 Zn-3 Cu based alloys,Al-25 Zn-3 Cu,Al-25 Zn-3 Cu-0.01 Ti,Al-25 Zn-3 Cu-3 Si and Al-25 Zn-3 Cu-3 Si-0.01 Ti alloys were produced by permanent mold casting method.Microstructures of the alloys were examined by SEM.Hardness and mechanical properties of the alloys were determined by Brinell method and tensile tests,respectively.Tribological characteristics of the alloys were investigated by a ball-on-disc type test machine.Corrosion properties of the alloys were examined by an electrochemical corrosion experimental setup.It was observed that microstructure of the ternary A1-25 Zn-3 Cu alloy consisted ofα,α+ηandθ(Al2Cu)phases.It was also observed that the addition of 3 wt.%Si to A1-25Zn-3Cu alloy resulted in the formation of silicon particles in its microstructure.The addition of 0.01 wt.%Ti to the Al-25Zn-3Cu and Al-25 Zn-3 Cu-3 Si alloys caused a decrement in grain size by approximately 20%and 39%and an increment in hardness from HRB 130 to 137 and from HRB 141 to 156,respectively.Yield strengths of these alloys increased from 278 to 297 MPa and from 320 to 336 MPa while their tensile strengths increased from 317 to 340 MPa and from 334 to 352 MPa.Wear resistance of the alloys increased,but corrosion resistance decreased with titanium addition.

Effects of additives on corrosion and wear resistance of micro-arc oxidation coatings on TiAl alloy

Ceramic coating was deposited on TiAl alloy substrate by micro-arc oxidation(MAO)in a silicate-aluminate electrolyte solution with additives including sodium citrate,graphite and sodium tungstate.The microstructures and compositions were analyzed by SEM,EDX and XRD.The corrosion and wear properties of the coatings were investigated by potentiodynamic polarization and ball-on-disc wear test,respectively.The results show that the MAO coatings consist of WO3,Ti2O3,graphite and Al2O3 besides Al2TiO5 and Al2SiO5.With additives in the electrolyte,the working voltage at the micro-arc discharge stage decreases,and the ceramic coating gets smoother and more compact.The corrosion current density of MAO coating is much lower than that of TiAl substrate.It can be reduced from 9.81×10-8A/cm 2to 3.02×10-10A/cm 2 .The MAO coatings composed of hard Al2O3,WO3 and Ti2O3 obviously improve the wear resistance of TiAl alloy.The wear rate is-3.27×10-7g/(N·m).

STUDY ON THE EROSION-CORROSION BEHAVIOR OF STEELS AND THERMAL SPRAYED COATINGS

16Mn steel, 1Cr18Ni9 stainless steel, thermal sprayed Al2O3-TiO2 ceramic coating and nylon1010-5 %Al2O3 coating were tested with an erosion -corrosion tester.The effects of pH values and slurry velocities on the erosion-corrosion behavior of the materials tested were determined. The erosion-corrosion behavior of the materials tested changes with pH values and presents different change tendencies. The erosion-corrosion rates of the materials are increased with slurry velocities. The erosion-corrosion mechanisms for the steels and the coatings are considerably different.

高硼铸钢的研究进展

高硼铸钢是以B为主要合金元素的新型耐磨材料。围绕高硼铸钢组织中的Fe_2B,简单介绍了合金元素对高硼铸钢组织及力学性能的影响。然而,除耐磨以外,高硼铸钢在耐高温熔体(Zn、Al)腐蚀方面也展现出优异的性能。结合笔者已有的研究成果,重点介绍了新型高硼铸钢的耐铝液腐蚀及耐铝液腐蚀-磨损性能,硼化物对改善高硼铸钢的耐铝液腐蚀及耐铝液腐蚀-磨损性能起到了非常重要的作用。富Cr和富Mo的Fe_2B在铝液腐蚀过程中表现出不同的行为:富Cr的Fe_2B与铝液反应生成周期性层片结构,而富Mo的Fe_2B则是发生断裂、剥落;在铝液腐蚀-磨损过程中,初生富Cr的Fe_2B发生Fe元素的优先溶解,之后在磨损的作用下开裂、剥落,但相关机理还需深入研究。最后,对高硼铸钢的研究进行了展望。