Oxidation and Corrosion Resistance of NiCr-Re and NiCr-Re-Al2O3 Materials Fabricated by Spark Plasma Sintering

The thermal and oxidation resistance of elements found in the combustion boilers of power generation plants are some of the most important factors deciding their effectiveness. This paper shows the experimental results of the influence of NiCr-based material composition on the microstructure and phase changes occurring during the oxidation and corrosion process. NiCr alloy was modified by the addition of rhenium and aluminum oxide. Materials were densified using the spark plasma sintering method at a sintering temperature of 1050 °C. Oxidation tests conducted up to 1100 °C under synthetic airflow revealed the formation of a thin Cr2O3 layer protecting the material against in-depth oxidation. Results of electrochemical corrosion in a 0.5 M NaCl solution indicated a positive role of Re and Al2O3 addition, confirmed by low corrosion current density values in comparison to the other reference materials. According to the provided positive preliminary test results, we can conclude that a NiCr-Re-Al2O3 system in coating form was successfully obtained by the plasma spraying method.

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Technology of Ti-Al-Nb Obtaining by Use of Spark Plasma Sintering Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.743.41 ◽

2017 ◽

Vol 743 ◽

pp. 41-44

Author(s):

Ernat Kozhahmetov ◽

Batyrzhan Karakozov ◽

Sherzod Rustambekovich Kurbanbekov

Keyword(s):

Spark Plasma Sintering ◽

Phase Changes ◽

Effective Control ◽

Optimal Regime ◽

Plasma Sintering ◽

Diffusion Controlled ◽

Spark Plasma ◽

New Type ◽

Sintering Method ◽

Resistance To Heat

This method grants effective control of the porosity of the sintering materials and ability to obtain compactly packed samples, where simple pressing is not feasible. Spark plasma sintering is one of the probable methods that could lead to larger energy efficiency in material manufacturing. Upon use of SPS, there is no need to “pre-heat” the material by use of pressure or additional use of connecting agents or components. Manufacture of the components is being finished at the instant. Initial microstructure of the powder is being saved. Besides, with use of analyzing method, it is possible to obtain material of the new type, ones that are have resistance to heat. Use of SPS technology could imply lesser time of sintering for highly packed specimens. Decrease of time implies decrease of microstructural changes as a result of diffusion controlled phase changes. Taking into account what has been mentioned above, choosing the best suitable regime for Ti-Al-Nb proposes a variety of intermetallic junctions and could be used for creation of alloys with different physical-mechanical properties. This study concentrates on optimal regime of obtaining intermetallic junction based on Ti-Al-Nb with use of spark plasma sintering.

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Investigation of Microstructure and Corrosion Resistance of Ti-Al-V Titanium Alloys Obtained by Spark Plasma Sintering

Metals ◽

10.3390/met11060945 ◽

2021 ◽

Vol 11 (6) ◽

pp. 945

Author(s):

Aleksey Nokhrin ◽

Pavel Andreev ◽

Maksim Boldin ◽

Vladimir Chuvil’deev ◽

Mikhail Chegurov ◽

...

Keyword(s):

Corrosion Resistance ◽

Titanium Alloys ◽

Spark Plasma Sintering ◽

High Resistance ◽

Electrochemical Corrosion ◽

High Hardness ◽

Acidic Aqueous Solution ◽

Plasma Sintering ◽

Salt Corrosion ◽

Spark Plasma

The research results of the microstructure and corrosion resistance of Ti and Ti-Al-V Russian industrial titanium alloys obtained by spark plasma sintering (SPS) are described. Investigations of the microstructure, phase composition, hardness, tensile strength, electrochemical corrosion resistance and hot salt corrosion of Ti-Al-V titanium alloy specimens were carried out. It was shown that the alloy specimens have a uniform highly dense microstructure and high hardness values. The studied alloys also have high resistance to electrochemical corrosion during tests in acidic aqueous solution causing the intergranular corrosion as well as high resistance to the hot salt corrosion. The assumption that the high hardness of the alloys as well as the differences in the corrosion resistance of the central and lateral parts of the specimens are due to the diffusion of carbon from the graphite mold into the specimen surface was suggested.

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Electrochemical corrosion and bioactivity of titanium–hydroxyapatite composites prepared by spark plasma sintering

Corrosion Science ◽

10.1016/j.corsci.2013.01.032 ◽

2013 ◽

Vol 70 ◽

pp. 212-220 ◽

Cited By ~ 52

Author(s):

Anawati ◽

Hiroaki Tanigawa ◽

Hidetaka Asoh ◽

Takuya Ohno ◽

Masahiro Kubota ◽

...

Keyword(s):

Spark Plasma Sintering ◽

Electrochemical Corrosion ◽

Plasma Sintering ◽

Spark Plasma

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Enhanced Erosion–Corrosion Resistance of Tungsten by Carburizing Using Spark Plasma Sintering Technique

Materials ◽

10.3390/ma13122719 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2719 ◽

Cited By ~ 1

Author(s):

Yan Jiang ◽

Junfeng Yang ◽

Zhuoming Xie ◽

Qianfeng Fang

Keyword(s):

Corrosion Resistance ◽

Spark Plasma Sintering ◽

Intergranular Corrosion ◽

Water System ◽

Electrochemical Corrosion ◽

Coated Sample ◽

Flowing Water ◽

Plasma Sintering ◽

Spark Plasma ◽

Superior Corrosion Resistance

The biggest obstacle for the application of tungsten as the target materials in the spallation neutron source is its serious corrosion in the coolant of flowing water. For this reason, W–Cr–C clad tungsten was developed by tungsten carburizing in a spark plasma sintering device, with superior corrosion resistance in the static immersion and electrochemical corrosion test. This work focused on its erosion and corrosion performance in a flowing water system, based upon test parameters simulated under the service conditions. W–Cr–C clad tungsten showed superior corrosion resistance to that of bare tungsten due to the corrosion form changing from the intergranular corrosion of bare tungsten to pitting corrosion of W–Cr–C coating. The corrosion rate of tungsten was as high as tenfold that of the coated sample at 20 °C, and at most fourfold at 60 °C after testing for 360 h. Effects of water velocity and temperature on pitting and intergranular corrosion were investigated in detail and their corresponding corrosion mechanisms were analyzed and discussed.

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Preparation of Cerium Stabilized Zirconia Bulk Ceramics by Spark Plasma Sintering

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.405.396 ◽

2020 ◽

Vol 405 ◽

pp. 396-401

Author(s):

Marek Vojtko ◽

Alexandra Kovalcikova ◽

Viktor Puchý ◽

Ondrej Milkovič

Keyword(s):

Spark Plasma Sintering ◽

Phase Changes ◽

Sintering Process ◽

X Ray Diffraction ◽

Stabilized Zirconia ◽

X Ray ◽

Microstructure Observation ◽

Structure Changes ◽

Plasma Sintering ◽

Spark Plasma

In the present study, bulk 10 % cerium stabilized zirconia was prepared by spark plasma sintering technique. Various time temperatures regimes were used and prepared sample were subjected to microstructure observation by electron microscopy and X-ray diffraction and mechanical testing by nanoindentations. It was shown, that conditions of spark plasma sintering process can strongly influence properties of resultant sample, mainly grain size which warried from some tens or hundreds of nanometre to approximately 100 micrometres. Also some structure changes in the sintering process were observed resulted to phase changes and decomposition.

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