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Article
Publication date: 23 September 2021

Yabao Hu, Hanning Chen, Xiaodan Liang and Jianbo Lei

Studies on titanium implants have shown that the mechanical properties of the parts are affected by the microstructure characteristic derived from the manufacturing…

Abstract

Purpose

Studies on titanium implants have shown that the mechanical properties of the parts are affected by the microstructure characteristic derived from the manufacturing process. The properties of different orientations of specimens under the same process parameters will be different, which should be considered in the application of bone implants. This paper aims to understand the influence of microstructure on micro-hardness, wear and corrosion resistance in different orientations.

Design/methodology/approach

The authors manufactured titanium parts and carried out micro-hardness, wear tests and electrochemical corrosion of different orientations under the same process conditions. Then, finally studied the evolution mechanism of the microstructure in different orientations and its influence mechanism on wear and corrosion mechanism.

Findings

The melting method makes the grains on the surface in XY orientation finer. The wear mechanism of XY orientation is abrasive wear, that of XZ and YZ orientations are adhesive wear. During corrosion, XY orientation forms a stable passivation film earlier. Compared with XZ and YZ orientations, XY orientation has higher micro-hardness, better wear and corrosion resistance.

Originality/value

In this paper, the microstructure, wear and corrosion resistance of selective laser melted parts were discussed and the differences in different orientations under the same experimental conditions were discussed. The evolution mechanism of the microstructure in different orientations and its influence mechanism on wear mechanism and corrosion mechanism was studied. The mechanical anisotropy of selective laser melted components was discussed.

Details

Rapid Prototyping Journal, vol. 28 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 January 2016

Xianghong Lv, Guoxian Zhao, Fuxiang Zhang, Xiang Tong Yang, Dan Ba, Junfeng Xie and Yan Xue

The purpose of this investigation was to study the function mechanisms of a corrosion inhibitor package used for martensitic stainless steel tubulars in acid solution at…

Abstract

Purpose

The purpose of this investigation was to study the function mechanisms of a corrosion inhibitor package used for martensitic stainless steel tubulars in acid solution at high temperatures.

Design/methodology/approach

The inhibition performance was evaluated by means of an acid corrosion test at high temperature and high pressure, and the functional mechanism of the inhibitor package at different temperatures was investigated using polarization curve and electrochemical impedance spectroscopy measurements.

Findings

The results showed that the corrosion inhibitor package chosen for high-temperature and high-pressure gas well applications was very suitable for use with 13Cr super martensitic stainless steel. At lower temperatures, the function mechanism of the corrosion inhibitor package was characterized as a type of negative catalytic effect. As the temperature was increased, the effect of the intensifier in the package became more significant and the function mechanism changed to be the geometric covering effect type.

Originality/value

This study has the important practical value for guiding the oil field to conduct reasonable screening and using the acidizing corrosion inhibitor for martensite stainless steel tubulars.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 31 January 2020

Hailing Li, Hongxia Wan, Shengrong Wang, Cuiwei Du and Dawei Zhang

This paper aims to investigate the effect of alternating current (AC) on corrosion, it is not yet clear about the exact mechanism of the corrosion induced by AC. Previous…

Abstract

Purpose

This paper aims to investigate the effect of alternating current (AC) on corrosion, it is not yet clear about the exact mechanism of the corrosion induced by AC. Previous reports indicated that AC corrosion was similar to the effect of continuous cathodic and anodic polarization on the corrosion process of the metals. Wan et al. studied the effect of negative half-wave AC on stress corrosion cracking behavior and mechanism of X80 pipeline steel in near-neutral solution.

Design/methodology/approach

This study attempted to understand the AC-induced corrosion by imposing the half-cycle AC on the X80 pipeline steel in an acid bicarbonate solution. The AC corrosion mechanism was determined by weight loss and potentiodynamic polarization curve measurements, as well as surface characterization.

Findings

The results show that the positive half-cycle AC accelerated the uniform corrosion in the NaHCO3 solution, the negative half-cycle AC would decrease the uniform corrosion and local corrosion was increased and some Ca and Mg deposited on the surface of X80 steel, so the corrosion rate decreased by negative half-cycle AC. The corrosion product was composed of α-FeOOH under the application of positive half-cycle AC. The oxygen reduction led to a local increase of pH near the electrode surface and led to the formation of α-FeOOH, which enhanced the protectability of corrosion products.

Originality/value

Researchers studied the effect of negative half-wave AC on stress corrosion cracking behavior and mechanism of X80 pipeline steel in near-neutral solution. However, the AC behavior and corrosion mechanism in acid solution are unknown. So to make clear about the corrosion behavior of metals in different polarization states and the mechanism involved, diode technology was used to research the AC corrosion, half-wave AC was applied on the metals after the full-wave rectified.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 21 June 2013

Dong Liu, Huiqing Liu, Li Li, Meng Yu, Jun Gong, Wen Li and Yunxia Wang

The purpose of this paper is to assess the serious corrosion problems of the water injection system on the offshore oil field and to study the type, and effect factors and…

Abstract

Purpose

The purpose of this paper is to assess the serious corrosion problems of the water injection system on the offshore oil field and to study the type, and effect factors and mechanisms of corrosion on the offshore oil field in order to develop an effective corrosion inhibitor for the sea water injection system.

Design/methodology/approach

The corrosion of metal in a water injection system was studied by weight‐loss and electrochemical methods.The effect factors and mechanisms of corrosion on the offshore oil field were proposed from the trend of corrosion.

Findings

FeCO3 is the main corrosion product in the water injection system of the Chengdao Offshore Oil Field. The corrosion rate of coupons in sea water injection systems reaches a maximum peak at a temperature of 50‐60°C. The corrosion rate of coupons exposed in all three water samples increased with an increase in the dissolved oxygen concentration. When the mixed ratio of sea water and produced water and well water is 1:3:1 or 1:2:2, the corrosion rate of carbon steel is lower than is the case in pure water. The electrochemical mechanism of corrosion indicates that corrosion in the well water, produced water, and sea water samples were all controlled by the oxygen absorption process, which controlled the cathodic reaction. The corrosion rate of coupons followed the ranking order: well water; produced water; sea water.

Originality/value

This paper provides the main corrosion product in the water injection system of the Chengdao Offshore Oil Field, and provides new information on the effect factors and mechanisms of corrosion on the offshore oil field.

Details

Anti-Corrosion Methods and Materials, vol. 60 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 2 September 2021

Lei Fu, Hui Li, Li Lin, Qingyuan Wang, Qi Fan, Xinjie Huang, XiuLan Li, Sheng Lai and Lifei Chen

Most supersonic aircraft were manufactured using 2A70 aluminum alloy. The purpose of this paper is to study the corrosion mechanism and fatigue behavior of an aircraft in…

Abstract

Purpose

Most supersonic aircraft were manufactured using 2A70 aluminum alloy. The purpose of this paper is to study the corrosion mechanism and fatigue behavior of an aircraft in a semi-industrial atmospheric corrosive environment, alternating effects of corrosion and fatigue were used to simulate the aircraft’s ground parking corrosion and air flight fatigue.

Design/methodology/approach

For this purpose, the aluminum alloy samples were subjected to pre-corrosion and alternating corrosion-fatigue experiments. The failure mechanisms of corrosion and corrosion fatigue were analyzed using microscopic characterization methods of electrochemical testing, X-ray diffraction and scanning electron microscopy. Miner’s linear cumulative damage rule was used to predict the fatigue life of aluminum alloy and to obtain its safe fatigue life.

Findings

The results showed that the corrosion damage caused by the corrosive environment was gradually connected by pitting pits to form denudation pits along grain boundaries. The deep excavation of chloride ions and the presence of intergranular copper-rich phases result in severe intergranular corrosion morphology. During cyclic loading, alternating hardening and softening occurred. The stress concentration caused by surface pitting pits and denudation pits initiated fatigue cracks at intergranular corrosion products. At the same time, the initiation of multiple fatigue crack sources was caused by the corrosion environment and the morphology of the transient fracture zone was also changed, but the crack propagation rate was not basically affected. The polarization curve and impedance analysis results showed that the corrosion rate increases first, decreases and then increases. Fatigue failure behavior was directly related to micro characteristics such as corrosion pits and microcracks.

Originality/value

In this research, alternating effects of corrosion and fatigue were used to simulate the aircraft’s ground parking corrosion and air flight fatigue. To study the corrosion mechanism and fatigue behavior of an aircraft in a semi-industrial atmospheric corrosive environment, the Miner’s linear cumulative damage rule was used to predict the fatigue life of aluminum alloy and to obtain its safe fatigue life.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 November 1986

Zaki Ahmad

The relatively complex corrosion mechanism of aluminium has been studied by several authors. Corrosion of aluminium occurs only when the metal protective oxide layer is…

Abstract

The relatively complex corrosion mechanism of aluminium has been studied by several authors. Corrosion of aluminium occurs only when the metal protective oxide layer is damaged and when the repair mechanism is prevented by chemical dissolution. Polarization methods have been extensively used to investigate the mechanism of localised corrosion and processes that lead to localised corrosion. The potential‐pH diagrams are shown in Fig. 1A. In using potentiostatic techniques, the potential is controlled and current is determined as the independent variable. Potentiostatic and potentiody‐namic techniques have been applied by several authors to study the corrosion of aluminium in different environment. Both anodic and cathodic polarization curves have been used to interpret the kinetics of pitting corrosion of aluminium in chloride containing environments. Both the anodic and cathodic process are complex and the interpretation of the anodic and cathodic polarization curves of aluminium is often tedious. The situation arises partly from the fact that the role of film formation on the kinetics of corrosion is not clearly understood. Previously there is not established mechanisms of initiation and propagation of pits in aluminium and its alloys. Several parameters such as pitting potential, breakdown potential, active passive transition potential, related to the pitting process of aluminium, are full of controversy. Numerous references on the above can be found in literature).

Details

Anti-Corrosion Methods and Materials, vol. 33 no. 11
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 6 November 2017

Liqiang Zhao, Yanhua Zhu, Pingli Liu, Jian Zhang and Yigang Liu

This paper aims to describe the corrosion behavior and possibility of inhibition by corrosion inhibitor SA1-3 in acidizing solution (5 per cent hydrochloric acid [HCl…

Abstract

Purpose

This paper aims to describe the corrosion behavior and possibility of inhibition by corrosion inhibitor SA1-3 in acidizing solution (5 per cent hydrochloric acid [HCl] solution). The study aims to explain the mechanism of corrosion and inhibition of N80 steel in 5 per cent HCl solution to provide theoretical basis for expanding the range of application of N80 steel in acidification process.

Design/methodology/approach

This paper opted for a laboratory study using simulation of acidizing solution to do the experiments. The results of experiments including weight-loss method, electrochemical method and surface analysis were used to explain the mechanism of corrosion and inhibition so as to predict the dissolution progress of N80 steel in 5 per cent HCl solution with and without inhibitor SA1-3.

Findings

This paper provides theoretical insights about how to inhibit the corrosion behavior of N80 steel in 5 per cent HCl solution. It suggests that the corrosion inhibitor which can form a protective film on the steel surface should be used to expand the application of N80 steel in acidizing solution. The inhibitor SA1-3 is a kind of cathodic corrosion-controlling inhibitor which mainly inhibits cathode corrosion; it cannot change the corrosion mechanism of N80 steel.

Originality/value

This paper provides a theoretical basis for the corrosion behavior and inhibition mechanism of N80 steel in acidizing solution.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 15 June 2021

Olanrewaju Moses Adesusi, Olayide Rasaq Adetunji, Tunji John Erinle, Iliyasu Kayode Okediran, Olumide Olufunso Akinpelu and Samuel Oluyemi Ipadeola

The purpose of this paper is to investigate the mechanisms of low alloyed medium-carbon steel (LAMCS) corrosion in 0.5 M H2SO4 inhibited by seeds oils of rubber (SOR)…

Abstract

Purpose

The purpose of this paper is to investigate the mechanisms of low alloyed medium-carbon steel (LAMCS) corrosion in 0.5 M H2SO4 inhibited by seeds oils of rubber (SOR), Neem (SON) and Jatropha (SOJ) containing varying degree of free fatty acid (FFA).

Design/methodology/approach

Specific gravity, acid values and FFA compositions of oils were determined. Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and X-ray diffraction (XRD) are techniques used to investigate the corrosion inhibition mechanisms with evaluated Gibbs free energy of adsorption.

Findings

Corrosion inhibition efficiencies of oils reached values >99% as obtained from PDP and EIS. Protective oxide layer was formed on LAMCS consequent on containment of carbonyl and hydroxyl groups in the FFA of SOR, SON and SOJ, respectively. The SOR and SOJ are found to be mixed inhibitors, whereas SON behaved as anodic inhibitor. Mechanism of adsorption of SOR was synergistic between physisorption and chemisorption, while SON and SOJ exhibited physisorption. SEM micrographs images showed that uninhibited sample exhibited thicker mass of corrosion products. Formation of protective oxide layer was confirmed by XRD diffractograms.

Practical implications

This study has shown that the need for modification of vegetable seed oils containing FFA is unnecessary as the hydroxyl and carbonyl groups of the FFA contained in the respective oil were found to be the center of adsorption of the oils on the steel surface. Hence, cost and by-products associated with modification of oils used as corrosion inhibitors are eliminated.

Originality/value

SOR, which has the highest percentage FFA, was found to be the most influential on the corrosion inhibition mechanism of LAMCS, specifically within 0.01–0.02 g/mL concentration. FFA contained in the respective seed oil aided formation of protective oxide layer at interface between H2SO4 and LAMCS, relative to amount composed.

Article
Publication date: 31 January 2020

Hui Li, Lei Fu, Li Lin, Yu Chen, YunRong Luo, XiuLan Li, WenLing Xie and Qingyuan Wang

In summary, it can be found that the current research on the simulation of natural atmospheric dry–wet alternating accelerated corrosion mainly focused on the study of…

Abstract

Purpose

In summary, it can be found that the current research on the simulation of natural atmospheric dry–wet alternating accelerated corrosion mainly focused on the study of electrochemical corrosion process and the study of corrosion rate; the micro-pre-corrosion mechanism of materials in this environment, especially for materials. The specific effects of fatigue and fracture performance still lack detailed research. Accordingly, this study aims to more realistically simulate the effect of natural atmospheric corrosion environment on the corrosion resistance and fatigue performance of aircraft skin.

Design/methodology/approach

In this study, the uniaxial strain control method was used to test the fatigue performance of pre-corrosion samples under simulated natural atmospheric corrosion using MTS809 tensile-torque composite fatigue machine. Scanning electron microscopy, X-ray energy spectrum analysis, atomic force microscopy and X-ray diffraction analysis were used. Fatigue fracture, corrosion morphology and corrosion products were analyzed.

Findings

The results show that the deep corrosion pit caused by pre-corrosion environment leads to multi-source initiation of crack; the fatigue life of pre-corroded sample decreases by about one-half, chloride ion invades the material and promotes intergranular corrosion; life prediction results show that the natural atmospheric corrosive environment mainly affects the plastic term in the Manson–Coffin formula resulting in a decrease in fatigue life.

Originality/value

Innovative experimental schemes and materials are used and the test temperature and relative humidity are strictly controlled. The corrosion failure mechanism of 2A70-T6 aluminum alloy under alternating wet and dry accelerated corrosion environment and its influence on fatigue behavior were obtained.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 20 October 2021

Yingwei Liu, Zhe Wang, Chuang Liu and Jingming Ma

This study aims to reveal the differential concentration corrosion (DCC) mechanism, which has been ignored by researchers for a long time.

Abstract

Purpose

This study aims to reveal the differential concentration corrosion (DCC) mechanism, which has been ignored by researchers for a long time.

Design/methodology/approach

The ionic conductive layer near the pipe wall was extracted and discretized. In the case of DCC, the equations of corrosion potential after polarization in units are derived according to Kirchhoff’s Law. By solving these equations, the corrosion potential and current on situation of DCC are calculated.

Findings

DCC can change origin distribution of (nature) potential and current greatly; it will cause polarization. The positions with original lower corrosion potential will produce anodic polarization; meanwhile, the speed of corrosion also increases; the position with original higher corrosion potential will produce cathodic polarization, and the corrosion current is also decreased. Generally speaking, the potential will be homogenized by DCC mechanism.

Originality/value

This model makes an in-depth analysis of the traditional FAC theory, greatly supplements it and enriches the theory.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

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