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The purpose of this paper is to investigate the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

Al₂O₃ particles and 10 wt% NaCl solution are used to evaluate erosion and corrosion resistance of WC-Ni vacuum brazed coating. Combined test of erosion and corrosion is also conducted. The microstructure of each specimen is characterized by the scanning electron microscopy. The chemical composition was determined by energy-dispersive X-ray spectroscopy.

WC-Ni vacuum brazed coating layer is effective protective coating under combined erosion and corrosion environment. The weight loss of coating layer is more reduced as the cumulative test time.

WC-Ni vacuum brazed coatings are investigated to check characteristic of the combined erosion and corrosion environment. WC-Ni vacuum brazed coatings are kind of diffusion coating that attract attention because of the resistance of superb impact and corrosion in comparison with other coatings. Some previous researches reported the properties of vacuum brazed WC material. Erosion and corrosion behaviors of WC-Ni vacuum brazed coatings were studied in our previous research, respectively. Hence, in this research, the principal objective is to examine the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

Transportation of solids by slurry pipeline is a rapidly growing field. The pipelines, in the process of transportation undergo severe deterioration externally as well as internally. Corrosion‐erosion, metal damage caused by the combined action of electrocemical corrosion and mechanical erosion, has been studied extensively. In hydraulic transportation of sand, internal wear is caused by combined action of corrosion, associated with the corrosive water, the flow velocity and abrasion due to geometry of the solid particles on the interior pipe wall. Corrosion in slurry pipeline is generally due to the presence of dissolved oxygen in the slurry. The control of corrosion wear in a coal slurry pipeline is reported by Bomberger. The corrosion study by Postlethwaite and Tinkler showed that the presence of solids in commercial concentration increases the rate of corrosion in pipelines. The most common erosion occurred generally is the scratching or grooving of the pipe by the slurry particles. An erosion‐corrosion study in pilot plant slurry transportation in pipeline carrying wide range of water borne solids such as coal, iron ore and sand have shown that the presence of solids increases the chemical corrosion rate, apart from any accompanying erosion. It was also observed that due to severe corrosion‐erosion problem in pipeline, even a pinhole in such a line would be enlarged gradually in a matter of minutes by the out flow of high pressure abrasive slurry. Jacues and Neil had given an account of the causes, control and the economics of internal corrosion of slurry pipelines Zabell et. al. had studied the effect of bacteria using six different processes on corrosion of iron and the steel water pipes. The copper pipe line had been specially studied by Fischer and few others in various environments.

This paper seeks to summarise the results of available research on the use of high velocity oxy‐fuel (HVOF) thermal‐spray technique to provide protection against high temperature corrosion and erosion‐corrosion of materials.

This paper describes one of the recent thermal‐spray processes, namely HVOF thermal‐spray technology and presents a survey of the studies on the use of this technique to provide protection against corrosion and erosion‐corrosion of high temperature alloys, with a special emphasis on boiler steels.

High temperature corrosion and erosion‐corrosion are serious problems observed in steam‐powered electricity generation plants, gas turbines, internal combustion engines, fluidized bed combustors, industrial waste incinerators and recovery boilers in paper and pulp industries. These problems can be prevented by changing the material or altering the environment, or by separating the component surface from the environment. Corrosion prevention by the use of coatings for separating materials from the environment is gaining importance in surface engineering. Amongst various surface modifying techniques, thermal spraying has developed relatively rapidly due to the use of advanced coating formulations and improvements in coating application technology. One of the variants of thermal spraying, namely HVOF has gained popularity in recent times due to its flexibility for in‐situ applications and superior coating properties.

This review covers mainly information that has been reported previously in the open literature, international journals and some well‐known textbooks.

The paper presents a concise summary of information for scientists and academics, planning to start their research work in the area of surface engineering.

This paper fulfils an identified information/resources need and offers practical help to an individual starting out on a career in the area of surface engineering for erosion‐corrosion and wear.

The purpose of this paper is to study the corrosion behavior of 316L stainless steel under cavitation condition in simulated seawater.

Electrochemical impedance spectroscopy and electrochemical noise analyses are used to characterize the electrochemical process during the cavitation erosion process.

Because of good corrosion resistance of this material, mechanical damage is the main cause of cavitation erosion. The alloy surface is in active dissolution state during the cavitation erosion process, and the corrosion rate is accelerated as time prolongs which is verified by electrochemical results.

Electrochemical noise is an effective way to study the corrosion under cavitation erosion process.

To make clear that C‐steel can differ very much in corrosion resistance under practical conditions only because of differences in chemical composition of the steels.

In the electricity generating industry, “mild” (i.e. “plain carbon”) and low‐alloyed steels are used in huge quantities, for instance, in boilers, steam generators, heat recovery boilers and waste incineration boilers. The resistance to strain induced corrosion cracking (SICC) was determined by measuring the “repassivation” behaviour of the steels at freshly ground surfaces with an electrochemical technique. The corrosion current measured with time was used to calculate the cracking rates of a compact tension specimen.

A correlation was found between chemical composition, corrosion resistance to SICC and experiences under practical conditions. The results of early‐published papers on boiler corrosion (testing in FeCl₂ solutions), erosion corrosion (testing in wet steam at 20 bar), nitrate stress corrosion cracking (testing in NH₄NO₃ solutions) and SICC together with those originating from in‐service failures, were compiled into a reference database. This paper is a compilation of this work too.

The database and formulas presented make clear there is often a direct correlation between chemical composition of ordinary C‐steel and mentioned types of corrosion failures. The paper is of importance to designers, failure analysts and researchers.

The purpose of this study is to investigate the application of Ni₃Al coating for boilers and other power plant equipment, which suffer severe erosion-corrosion problems resulting in substantial losses. Currently, superalloys are being used to increase the service life of the boilers. Although the superalloys have adequate mechanical strength at elevated temperature, they often lack resistance to erosion-corrosion environments.

In this paper, the erosion-corrosion performance of plasma-sprayed nickel aluminide (Ni₃Al) coating on nickel- and iron-based superalloys have been evaluated by exposing them to the low temperature primary superheater zone of the coal-fired thermal power plant at the temperature zone of 540^°C for ten cycles of 100 h duration. The exposed products were analysed along the surface and cross-section using scanning electron microscopy (SEM), X-ray diffraction (XRD) and electron micro probe analysis (EPMA).

The XRD, SEM and EPMA analyses have shown the formation of mainly NiO, NiAl₂O₄ and indicated the presence of Ni₃Al, Ni and Al₂O₃. In the boiler environment, Ni₃Al coating partially oxidizes and acts as a perfect barrier against erosion-corrosion of superalloys. The partially oxidised Ni₃Al coating remains intact even after 1,000 h cycle exposure.

The probable mechanism of attack for the plasma-sprayed Ni₃Al coating in the given boiler environment is presented.

The purpose of this paper is to clarify the effect of compressive stress on cavitation-erosion corrosion behavior of 304 stainless steel.

Compressive stresses of 60 MPa and 120 MPa were applied to 304 stainless steel through a self-designed loading device, and cavitation erosion-corrosion tests were performed using an ultrasonically vibratory apparatus. Scanning electron microscope and X-ray diffraction were used to analyze the microstructure evolution, and corrosion behavior was studied by electrochemical analysis.

The cavitation weight loss of 304 stainless steel decreased with the compressive stress. After cavitation corroded for 8 h, the weight loss for the specimen with 120 MPa compressive stress was 5.11 mg/cm², which was reduced by 56.7% from that of the specimen without loading stress (11.79 mg/cm²). The reason can be attributed to that compressive stress promoted the deformation-induced martensitic transformation during the cavitation process, which could not only provide a cushioning effect by absorbing cavitation impact energy but also improve the hardness of 304 stainless steel.

Compressive stress was found to restrain the cavitation damage on 304 stainless steel, and the corresponding mechanism was proposed.

The purpose of this paper is to study the cavitation erosion stages of AA5083 by electrochemical noise (EN).

EN technology including noise resistance and fast Fourier transform were used to characterize the electrochemical process during the cavitation erosion process.

AA5083 suffers from uniform corrosion during the cavitation erosion process. The whole cavitation erosion process can be divided into three stages: incubation stage, acceleration stage and steady-state stage. EN signals showed obvious differences in different stages of cavitation erosion.

EN technique is a suitable method that can be used to study cavitation erosion mechanism and identify cavitation erosion stages.

The paper aims to focus on the recognition of corrosion product morphologies of AA5083‐H321 corroding aluminum‐magnesium alloys used in the manufacture of aluminum high speed boats and submarines during flow induced corrosion in seawater.

All experiments were conducted in a 3.5 percent NaCl solution as the simulated marine environment. Hydrodynamic conditions were created by an rotating cylinder electrode (RCE) system. Morphological characterization of the surface was undertaken using SEM and EDAX techniques. Cyclic polarization tests were used to determine the electrochemical behavior of the alloy.

The results obtained reveal that the pit density on the sample surface increased with increasing the rotation speed. The enhanced flow condition also enhanced the tendency for intermetallic particles, including submicron size Al(Mg,Mn) inclusions, to promote pitting corrosion of the alloy. An interesting result was that crystallographic pitting occurred at rotation speeds greater than 5 m/s.

In the selection of corrosion control methods for high speed aluminum‐hulled boats, control of erosion corrosion was determined to be more important than any other form of corrosion.

Provides information about the contribution of mechanical and electrochemical corrosion phenomena in corrosion of high speed aluminum boats under hydrodynamic conditions. Characterization of new intermetallic particles in aluminum‐magnesium alloys that can promote pitting during flow induced corrosion in marine environments. Provides new information about the origin of crystallographic pitting attack on aluminum.

Erosion of turbine blades is a major cause of plant outage within the C.E.G.B., and the mechanism and methods of protection which have been adopted are described in some detail in this paper. The turbine outage time arising from corrosion causes is far less than that due to erosion but, nevertheless, a few persistent corrosion problems remain. These problems—the corrosion of white metal bearings, the seizing of 3% Cr‐Mo shafts and ‘blue blush’ of valves—are described. The first two of these are currently under investigation, whilst the latter has now been overcome by the use of alternative resistant materials