Preparation and Characterizations of NiTi Intermetallic Coatings

Much attention has been paid to NiTi intermetallic coating for enhancing cavitation erosion resistance property due to its shape memory effect. In this paper two processes were used to deposit NiTi intermetallic coatings. Process 1 was the deposition of NiTi intermetallic coating using warm spray process with NiTi intermetallic powder as feedstock, and solution treatment was subsequently performed. Process 2 was a mixture process of warm spray and laser treatment. Ni-Ti coating was first deposited via warm spray process with Ni-cladding Ti as feedstock, and laser-treatment was performed to realize the alloying of Ni-Ti. The microstructure and phase compositions for NiTi intermetallic coatings were characterized by means of SEM and XRD. The fundamental properties for NiTi intermetallic coatings were also analyzed.

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Effect of heat treatment on corrosion and ultrasonic cavitation erosion resistance of AlSi10MnMg alloy

Materials Testing ◽

10.1515/mt-2020-620910 ◽

2020 ◽

Vol 62 (9) ◽

pp. 921-926

Author(s):

Ion Dragoş Uţu ◽

I. Mitelea ◽

I. Bordeașu ◽

F. Franţ

Keyword(s):

Solid Solution ◽

Solution Structure ◽

Artificial Aging ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Eutectic Silicon ◽

Solution Treatment ◽

Mechanical Tests ◽

Ultrasonic Cavitation ◽

Cavitation Erosion Resistance

Abstract The investigated alloy is modified by casting with Sr in order to finish the eutectic silicon from microstructure and furthermore subjected to solution treatment followed by natural or artificial aging to improve the usage properties. Metallographic investigations and X-ray diffraction analyses showed that the heat treated microstructure consists of α- solid solution crystals with aluminum base, α + Si eutectic and intermetallic Al-Mn-Si phases. Mechanical tests and ultrasonic cavitation measurements showed that the highest mechanical characteristics and cavitation erosion resistance properties are obtained by applying the solution treatment followed by artificial aging. In contrast, electrochemical tests carried out in a saline concentration of 3.5 % NaCl in order to determine the corrosion rate, indicated that although there are no significant differences between the three structural states, a slight improvement was found in the corrosion behavior after applying the solution treatment followed by both natural and artificial aging. The phenomenon was demonstrated by shifting the values of corrosion currents from 2.66 μm/cm2 for the as-cast state, to 1.81 μm/cm2 and 1.52 μm/cm2, respectively, for the aged states. Finally, analysis of the cavitation eroded surface highlights the presence in the areas with α-solid solution structure of some flat-bottomed striped pinches, characteristic of fatigue fracture and of microcraters in the micro-zones where the fragile intermetallic phases were dislocated.

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Neural Modelling of APS Thermal Spray Process Parameters for Optimizing the Hardness, Porosity and Cavitation Erosion Resistance of Al2O3-13 wt% TiO2 Coatings

Processes ◽

10.3390/pr8121544 ◽

2020 ◽

Vol 8 (12) ◽

pp. 1544

Author(s):

Mirosław Szala ◽

Leszek Łatka ◽

Michał Awtoniuk ◽

Marcin Winnicki ◽

Monika Michalak

Keyword(s):

Thermal Spray ◽

Process Parameters ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Ceramic Coatings ◽

Thermal Spray Process ◽

Spray Process ◽

Tio2 Coatings ◽

Cavitation Erosion Resistance ◽

Selection Of

The study aims to elaborate a neural model and algorithm for optimizing hardness and porosity of coatings and thus ensure that they have superior cavitation erosion resistance. Al2O3-13 wt% TiO2 ceramic coatings were deposited onto 316L stainless steel by atmospheric plasma spray (ASP). The coatings were prepared with different values of two spray process parameters: the stand-off distance and torch velocity. Microstructure, porosity and microhardness of the coatings were examined. Cavitation erosion tests were conducted in compliance with the ASTM G32 standard. Artificial neural networks (ANN) were employed to elaborate the model, and the multi-objectives genetic algorithm (MOGA) was used to optimize both properties and cavitation erosion resistance of the coatings. Results were analyzed with MATLAB software by Neural Network Toolbox and Global Optimization Toolbox. The fusion of artificial intelligence methods (ANN + MOGA) is essential for future selection of thermal spray process parameters, especially for the design of ceramic coatings with specified functional properties. Selection of these parameters is a multicriteria decision problem. The proposed method made it possible to find a Pareto front, i.e., trade-offs between several conflicting objectives—maximizing the hardness and cavitation erosion resistance of Al2O3-13 wt% TiO2 coatings and, at the same time, minimizing their porosity.

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Neural Modelling of APS Thermal Spray Process Parameters for Optimising the Hardness, Porosity and Cavitation Erosion Resistance of Al2O3 -13% TiO2 Coatings

10.20944/preprints202011.0200.v1 ◽

2020 ◽

Author(s):

Mirosław Szala ◽

Leszek Łatka ◽

Michał Awtoniuk ◽

Marcin Winnicki ◽

Monika Michalak

Keyword(s):

Thermal Spray ◽

Process Parameters ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Ceramic Coatings ◽

Thermal Spray Process ◽

Spray Process ◽

Conflicting Objectives ◽

Cavitation Erosion Resistance ◽

Selection Of

The study aims to elaborate a neural model and algorithm for optimising hardness and porosity of coatings and thus ensure that they have superior cavitation erosion resistance. Al2O3-13wt.%TiO2 ceramic coatings were deposited onto 316L stainless steel by atmospheric plasma spray (ASP). The coatings were prepared with different values of two spray process parameters: the stand-off distance and torch velocity. Microstructure, porosity and microhardness of the coatings were examined. Cavitation erosion tests were conducted in compliance with the ASTM G32 standard. Artificial neural networks (ANN) were employed to elaborate the model, and the multi-objectives genetic algorithm (MOGA) was used to optimise both properties and cavitation erosion resistance of the coatings. Results were analysed with Matlab software by Neural Network Toolbox and Global Optimization Toolbox. The fusion of artificial intelligence methods (ANN+MOGA) is essential for future selection of thermal spray process parameters, especially for the design of ceramic coatings with specified functional properties. Selection of these parameters is a multicriteria decision problem. The proposed method made it possible to find a Pareto front, i.e. trade-offs between several conflicting objectives – maximising the hardness and cavitation erosion resistance of Al2O3-13%TiO2 coatings and, at the same time, minimizing their porosity.

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Effect of Solution Treatment Temperature upon the Cavitation Erosion Resistance of X5CrNi18-10 Stainless Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1111.116 ◽

2015 ◽

Vol 1111 ◽

pp. 116-120 ◽

Cited By ~ 2

Author(s):

Cornelia Laura Sălcianu ◽

Ilare Bordeaşu ◽

Ion Mitelea ◽

Corneliu Marius Crăciunescu

Keyword(s):

Stainless Steel ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Solution Treatment ◽

Treatment Temperature ◽

Solution Treatment Temperature ◽

Different Temperatures ◽

Cavitation Erosion Resistance ◽

Steel Heat ◽

Made In

The specimens subjected to cavitation erosion were quenched from different temperatures (1000°C, 1050°C and 1100°C) but maintained the same time (25 min.) at the high temperature. The cavitation tests were made in the T2 device of the Timisoara Polytechnic University Cavitation Laboratory. This device respects integrally the recommendation of the ASTM G32-2010 Standard. The specimens microstructure and the area subjected to cavitation were examined with optic and SEM microcopies and hardness measurements. The differences arising on cavitation erosion resistance are explained through modifications of the crystalline grains dimensions, the chromium carbides proportion and some intermetallic phases not dissolved in austenite and of resistance to plastic deformation.Keywords: stainless steel, heat treatment, cavitation erosion

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Effect of Solution Treatment on Cavitation Erosion Resistance of Duplex Stainless Steel Surfacing Layers

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.324.21 ◽

2021 ◽

Vol 324 ◽

pp. 21-25

Author(s):

Zi Rui Wang ◽

Ye Feng Bao ◽

Qi Ning Song ◽

Ke Yang ◽

Yong Feng Jiang

Keyword(s):

Stainless Steel ◽

Duplex Stainless Steel ◽

Incubation Period ◽

Stainless Steels ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Solution Treatment ◽

Duplex Stainless Steels ◽

Water Quenching ◽

Cavitation Erosion Resistance

In the present work, the possibility of using solution treatment to improve the cavitation erosion resistance of the duplex stainless steel surfacing layers was discussed. The effect of solution treatment on cavitation erosion resistance of duplex stainless steels was investigated. The results showed that the solution treatment can adjust the ratio of ferrite to austenite, reduce the precipitation content, and make the incubation period longer, leading to an increase in the cavitation erosion resistance of the duplex stainless steel surfacing layers. The sample treated at 900°C and water quenching was shown to have the best resistance to the absorption of the energy produced by cavitation erosion, and hence the best cavitation erosion resistance.

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Cavitation Erosion Resistance of Ti-Ni Intermetallic Coatings Prepared by Low Pressure Plasma Spray Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1058.265 ◽

2014 ◽

Vol 1058 ◽

pp. 265-269 ◽

Cited By ~ 2

Author(s):

Qiu Sheng Lin ◽

Ke Song Zhou ◽

Chun Ming Deng ◽

Chang Guang Deng ◽

Zi Qi Kuang ◽

...

Keyword(s):

Plasma Spray ◽

Cavitation Erosion ◽

Erosion Resistance ◽

Low Pressure ◽

Spray Process ◽

Pressure Plasma ◽

Plasma Spray Process ◽

Low Pressure Plasma Spray ◽

Low Pressure Plasma ◽

Cavitation Erosion Resistance

In the current work, low pressure plasma spray process (LPPS) was applied to deposit Ti-Ni intermetallic coatings with Ni-clad Ti powder as feedstock. The microstructure and phase transition of LPPS sprayed Ti-Ni coating were investigated. Cavitation erosion resistance was examined using a standard ultrasonic cavitation test. The coating mainly consisted of TiNi phase with a certain amount of Ti2Ni, Ni3Ti phase and a few Ti phase. A few pores concentrated on the boundaries of the sprayed splats. The TiNi coating exhibited excellent cavitation erosion resistance.

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