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The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.

This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.

There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.

It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.

The aim of the research is to investigate the influence of ceramic coating on the wear performance of machine parts.

Ductile cast iron parts were coated using ceramics. Three ceramics were used for this purpose. These coated parts were subjected to wear tests under a stable load. A pin‐on‐disc wear test apparatus was used.

As a result of this study, the following findings are reported: According to ASTM G 99‐90 pin‐on‐disc experiments, Cr₂O₃ was found to be best coating material with low wearing rate. Within row, Al₂O₃ and ZrO₂ can be given. According to the previous work, motor parts for example piston ring, cylinder liner and engine valve can be coated with ceramic. In this study, it is observed that the figure of merit is increased in this study. Only wearing data is given in this research. The other results are also supporter of the results taken from the wearing experiments. As a result, due to the decrease in heat loss and coaling stability of part can provide good results. With these, by coating there is a decrease in oil reduction.

Coatings were limited with three ceramics, a stable load was used, and coated parts were subjected to wear test.

For future work, instead of using other coating materials, Cr₂O₃ is used for the best coating material with low wearing rate. By this process, working life of the machine parts can be extended and a number of economical advantages may also be obtained.

This paper fulfills identified information needs and offers practical help to the industrial firms working with ceramic coating and also to the academicians working on wear of materials.

The manufacture of flexi‐rigid multilayer boards poses a number of problems which are not met with in ordinary multilayer production or in the making of plain flexible circuits. Steps have to be taken to overcome the poor dimensional stability of thin polyimide foils during processing and to ensure that those portions of the assembly which need to be rigid are bonded whilst flexible portions are left unbonded other than for a cover coat. Pressure on cover coated flexible areas must be maintained during bonding without allowing resin to now over these areas, and finally the bonded unit must be profiled, often with superimposed flexible areas of different shapes. This article describes some of the techniques used by a leading manufacturer to overcome these problems. Several of the processes described are covered by patents held by Exacta Circuits Ltd. This article is an extract from a forthcoming book ‘Handbook of Multilayer Printed Circuits’ to be published at the end of the year by Electrochemical Publications Ltd., 8 Barns Street, Ayr, Scotland.

The purpose of this paper is to present a serial produced industrial robot for thin‐type space solar cells (SSC), which is applied to perform the bonding process of SSC.

An optimized process of adhesive coating and bonding for SSC is designed, based on an analysis of hydromechanics model. In order to perform the process, a novel robot is developed, which mainly consists of a three‐axis Cartesian coordinates' motion platform, coating‐and‐bonding device, solar cell and glass cover orientation plate, control system, pneumatic system, constant temperature module, and industrial personal computer software. The coating and bonding operation is based on the three‐axis Cartesian coordinates' motion and the help of pneumatic system.

Compared with the experimental prototype and handwork, the robot is more effective and reliable for the bonding process of the thin‐type solar cells.

The robot is very useful to realize automatic production of SSC.

The purpose of this paper is to examine the performance of cold-sprayed Zn15Al alloy coating whether it is capable of protecting magnesium alloy from corrosion, and to compare it with arc-sprayed Zn15Al alloy coating.

In this paper, Zn15Al alloy coating was prepared with CS-6000 cold spraying system and HDX-800 arc-sprayed system. Corrosion behaviors of the two kinds of coatings were examined with potentiodynamic polarization curves methods combined with SEM, EDS, XRD, etc.

Corrosion behavior of cold-sprayed Zn15Al alloy coating is superior to arc-sprayed Zn15Al alloy coating. The bonding strength and density of cold-sprayed Zn15Al alloy coating is much higher than that of arc-sprayed Zn15Al alloy coating. The cold-sprayed coating has a dense structure which separate magnesium from corrosion medium completely. The samples behave as Zn15Al instead of AZ91D alloy. The coating has a low probability of pitting corrosion comparing with cold sprayed Al coating through potentiodynamic polarization curve.

Cold-sprayed Zn15Al coating can be used to improve the anticorrosion performance of magnesium significantly and low down the risk of pitting corrosion of coating.

Cold-sprayed Zn15Al coating is an environmentally friendly anticorrosion method for light alloy, which is also the most effective way among thermal spray, chemical vapor deposition, sol–gel, plating and anodizing or microarc oxidation.

The present paper used cold spray method to deposit Zn15Al coating, which has an overwhelming performance both in physical and anticorrosion to traditional thermal spray method.

Nature provides a wide range of structures with different functions, which can serve as a source of research concepts. Based on the bionics principle, a bionic structure was applied to drill pipe specimens to compare the bond strength of paint coatings with and without a bionic ring groove pattern machined on the substrate.

Using the Revetest Xpress Plus scratch tester, the bond strengths of the coatings on the drill pipe with and without the bionic structure were measured and the difference in bond strength was observed.

The critical scratch loads of the surface coatings were 12.77 and 5.4 N. Furthermore, the scratch curve from the plain sample had a larger fluctuation compared to the curve of the samples with bionic ring grooves.

This indicated that the application of a bionic pattern to the surface of the substrate could enhance the bond strength and the degree of mechanical adhesion between the coating and the surface of the drill pipe, which is beneficial for the anti-corrosion performance of the drill pipe.

The amorphous Al-Ni-Fe-Gd coatings were fabricated to improve anti-corrosion performance of offshore platforms.

The amorphous Al-Ni-Fe-Gd coatings were first fabricated on S355 steel using the laser thermal spraying.

The amorphous forming capability and corrosion resistance increases with the laser powers increasing.

The amorphous Al-Ni-Fe-Gd coatings were applied on S355 steel of offshore platforms to increase its long-term heavy and anti-corrosion protection.

The amorphous Al-Ni-Fe-Gd coatings were first fabricated using a laser thermal spraying, improving its anti-corrosion.

The aim of the research is to increase piston and engine performance by using ceramic coated pistons instead of pistons which are manufactured from aluminum alloys and having a coated flame chamber.

Thermal torch and thermal shock tests were performed on the pistons and some specimens of 1.5 mm thick were prepared according to ASTM standards; both have the same material characteristics. In the present work, plasma spray technique was used for ceramic coating.

It was found that the ceramic coating, which, when performed properly, has compatible expansion coefficient with the aluminum alloy pistons, increases performance of pistons and engines.

Coatings were limited with one type of bonding and two ceramics, and coated parts were subjected to thermal torch and thermal shock tests.

For future work, instead of using other coating materials, stable yttria is used as the best coating material with optimum thermal resistance. By this process, working life of the machine parts can be extended and a number of economical advantages may also be obtained.

This paper fulfils the identified information and offers practical help to the industrial firms working with ceramic coatings and also to the academicians working on wear of materials.

The purpose of this paper is to improve binding force between the coating and the steel substrate by using chemical modification on the steel surface; at the same time, it can also increase the corrosion resistance of the coating.

The main components of the conversion film include tannic acid, sodium molybdate and silane coupling agent KH560. After the preparation was completed, the samples were tested and analyzed, including surface morphology, conversion film components, bonding force with organic resins and corrosion resistance. Finally, it drew a conclusion that the conversion film can greatly improve the bonding strength of the steel substrate and epoxy resin.

When the content of tannic acid is 4 g/L meanwhile the content of KH560 is 20 g/L, the conversion film has the strongest binding force with epoxy resin, from 2.15 Mpa of untreated steel to 4.60 Mpa, growth of 140 per cent. At the same time, the resulting conversion film also improves the corrosion resistance of the steel surface by a small margin.

A method of enhancing the bond between an epoxy coating and steel is provided. Verify the mechanism of this method.

Hot corrosion is the major degradation mechanism of failure of boiler and gas turbine components. The present work aims to investigate the hot corrosion resistance of detonation gun sprayed (D-gun) Cr₂O₃-75 per cent Al₂O₃ ceramic coating on ASTM-SA210-A1 boiler steel.

The coating exhibits nearly uniform, adherent and dense microstructure with porosity less than 0.8 per cent. Thermogravimetry technique is used to study the high temperature hot corrosion behavior of bare and coated boiler steel in molten salt environment (Na₂SO₄-60 per cent V₂O₅) at high temperature 900°C for 50 cycles. The corrosion products are analyzed by using X-ray diffraction, scanning electron microscopy (SEM) and field emission scanning electron microscope/energy-dispersive analysis (EDAX) to reveal their microstructural and compositional features for elucidating the corrosion mechanisms.

During investigations, it was found that the Cr₂O₃-75 per cent Al₂O₃ coating on Grade A-1 boiler steel is found to be very effective in decreasing the corrosion rate in the molten salt environment at 900°C. The coating has shown lesser weight gains along with better adhesiveness of the oxide scales with the substrate till the end of the experiment. Thus, coatings serve as an effective diffusion barrier to preclude the diffusion of oxygen from the environment into the substrate boiler steel.

Therefore, it is concluded that the better hot corrosion resistance of the coating is due to the formation of desirable microstructural features such as very low porosity, uniform fine grains and the flat splat structures in the coating; as compared to the bare substrate under cyclic conditions.

This research is useful for coal-fired boilers and other power plant boilers.

This research is useful for power generation plants.

There is no reported literature on hot corrosion behavior of Cr₂O₃-75 per cent Al₂O₃ coating deposited on the selected substrates by D-gun spray technique. The present work has been focused to study the influence of the Cr₂O₃-75 per cent Al₂O₃ coating developed with D-gun spraying technique on high temperature corrosion behavior of ASTM-SA210-A-1 boiler steel in an aggressive environment of Na₂SO₄-60 per cent V₂O₅ molten salt at 900°C under cyclic conditions.