Influence of Pre-Oxidation on High Temperature Oxidation and Corrosion Behavior of Ni-Based Aluminide Coating in Na2SO4 Salt at 1050°C

Aluminide coating is prepared on K438 Ni-based superalloy by pack cementation. The hot corrosion test of as-received and pre-oxidation aluminide coating in Na2SO4 salt are carried out at 1050°C. The coating morphologies, phase composition, and corrosion products are characterized by XRD, SEM, EDS, and TEM. The conclusion is that the pre-oxidation aluminide coating has excellent hot corrosion properties. After hot corrosion, the oxide scale of pre-oxidation aluminide coating is the thinnest and maintains good integrity. However, the oxide scale of as-received aluminide coating fluctuates greatly and there are corrosion cavities. CrS is formed in the alloy immediately below the oxide scale for the two coating systems.

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Effect of Arc Currents on the Mechanical, High Temperature Oxidation and Corrosion Properties of CrSiN Nanocomposite Coatings

Coatings ◽

10.3390/coatings12010040 ◽

2021 ◽

Vol 12 (1) ◽

pp. 40

Author(s):

Yanxiong Xiang ◽

Changwei Zou

Keyword(s):

High Temperature ◽

Friction Force ◽

High Temperature Oxidation ◽

Nanocomposite Coatings ◽

Corrosion Properties ◽

Temperature Oxidation ◽

Polarization Impedance ◽

Large Particles ◽

Arc Current ◽

Oxidation And Corrosion

In methods for multi-arc ion plating technology, the behavior and characteristics of the arc spot determine the physical characteristics of arc plasma and the properties of the subsequent deposited coatings. In this paper, the effect of arc currents on the hardness, friction coefficient, high temperature oxidation, and corrosion properties of the CrSiN coatings was studied. According to the XRD and SEM results, with the increase of arc currents, the coatings grew preferentially to the CrN (111) crystal direction, and the CrN (220) crystal phase appeared at high currents of 90 A. In addition, the number of large particles increased when the current exceeded 70 A. The HR-TEM results confirmed the formation of nanocomposite structure of nanocrystalline of CrN embedded into the amorphous phase of Si3N4 as explored by XRD. The maximum hardness was achieved at 3120 Hv when the coatings were deposited under currents around 70 A. However, the hardness values decreased with further increase of arc currents. From the contact of ceramic balls with the wear of coatings, the surface of coatings gradually produced friction marks, and the friction force increased from a steady friction force to a dynamic friction force. The high temperature oxidation results showed that fewer oxides were formed on the surface of the coatings when oxidized at 800 °C. It was also found that CrSiN nanocomposite coatings prepared at an arc current of 70 A had a larger corrosion potential and polarization impedance, which could effectively protect the tool matrix.

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High-temperature oxidation and hot corrosion behavior of the Cr-modified aluminide coating obtained by a Thermal Diffusion process

Materials Research Express ◽

10.1088/2053-1591/ab22f4 ◽

2019 ◽

Vol 6 (8) ◽

pp. 086444

Author(s):

Chong Li ◽

Xiaojing Xu ◽

Saifu Wang ◽

Vitus Mwinteribo Tabie ◽

Song Yang ◽

...

Keyword(s):

High Temperature ◽

Diffusion Process ◽

Thermal Diffusion ◽

Corrosion Behavior ◽

Hot Corrosion ◽

High Temperature Oxidation ◽

Aluminide Coating ◽

Temperature Oxidation ◽

Thermal Diffusion Process

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High Temperature Oxidation and Corrosion Properties of High Entropy Superalloys

Entropy ◽

10.3390/e18020062 ◽

2016 ◽

Vol 18 (2) ◽

pp. 62 ◽

Cited By ~ 31

Author(s):

Te-Kang Tsao ◽

An-Chou Yeh ◽

Chen-Ming Kuo ◽

Hideyuki Murakami

Keyword(s):

High Temperature ◽

High Temperature Oxidation ◽

Corrosion Properties ◽

Temperature Oxidation ◽

High Entropy ◽

Oxidation And Corrosion

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Friction and Wear of Oxide Scale Obtained on Pure Titanium after High-Temperature Oxidation

Materials ◽

10.3390/ma14133764 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3764

Author(s):

Krzysztof Aniołek ◽

Adrian Barylski ◽

Marian Kupka

Keyword(s):

High Temperature ◽

Oxide Scale ◽

High Temperature Oxidation ◽

Friction And Wear ◽

High Carbon Steel ◽

Oxide Films ◽

Oxidation Temperature ◽

Temperature Oxidation ◽

Wear Ratio ◽

Steel Balls

High-temperature oxidation was performed at temperatures from 600 to 750 °C over a period of 24 h and 72 h. It was shown in the study that the oxide scale became more homogeneous and covered the entire surface as the oxidation temperature increased. After oxidation over a period of 24 h, the hardness of the produced layers increased as the oxidation temperature increased (from 892.4 to 1146.6 kgf/mm2). During oxidation in a longer time variant (72 h), layers with a higher hardness were obtained (1260 kgf/mm2). Studies on friction and wear characteristics of titanium were conducted using couples with ceramic balls (Al2O3, ZrO2) and with high-carbon steel (100Cr6) balls. The oxide films produced at a temperature range of 600–750 °C led to a reduction of the wear ratio value, with the lowest one obtained in tests with the 100Cr6 steel balls. Frictional contact of Al2O3 balls with an oxidized titanium disc resulted in a reduction of the wear ratio, but only for the oxide scales produced at 600 °C (24 h, 72 h) and 650 °C (24 h). For the ZrO2 balls, an increase in the wear ratio was observed, especially when interacting with the oxide films obtained after high-temperature oxidation at 650 °C or higher temperatures. The increase in wear intensity after titanium oxidation was also observed for the 100Cr6 steel balls.

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High Temperature Oxidation of Metals (2) -Formation of Protective Oxide Scale

Zairyo-to-Kankyo ◽

10.3323/jcorr1991.44.416 ◽

1995 ◽

Vol 44 (7) ◽

pp. 416-417 ◽

Cited By ~ 1

Author(s):

Toshio Maruyama

Keyword(s):

High Temperature ◽

Oxide Scale ◽

High Temperature Oxidation ◽

Protective Oxide ◽

Temperature Oxidation ◽

Protective Oxide Scale

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Influences of Calcination Ambiences on Phase Composition and High Temperature Oxidation Resistance Property of Ceramic Coatings on Ti–6Al–4V Alloy by Micro-Plasma Oxidation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.2481 ◽

2007 ◽

Vol 336-338 ◽

pp. 2481-2483 ◽

Cited By ~ 6

Author(s):

Guo Dong Hao ◽

Zhao Hua Jiang ◽

Zhong Ping Yao ◽

Heng Ze Xian ◽

Yan Li Jiang

Keyword(s):

Phase Composition ◽

High Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Ceramic Coatings ◽

Plasma Oxidation ◽

Temperature Oxidation ◽

Complete Decomposition ◽

Weight Gains ◽

High Temperature Calcination

Compound ceramic coatings with the main crystalline of Al2TiO5 (as-coated samples) were prepared on Ti-6Al-4V alloy by pulsed bi-polar micro-plasma oxidation (MPO) in NaAlO2 solution. The coated samples were calcined in Ar and air at 1000oC, respectively. The phase composition, morphology and element content of the coatings were investigated by XRD, SEM and XRF. The samples treated in Ar and the as-coated ones were calcined in air at 1000oC to study the oxidation resistance of the samples. The results showed that Al2TiO5 decomposed and transformed into corundum and rutile TiO2 during the high temperature calcination. Al2TiO5 decomposed very quickly in air and the proportion of Al2O3 to TiO2 was 44:55 after a complete decomposition. On the contrary, Al2TiO5 decomposed very slowly in argon with the final proportion of Al2O3 to TiO2 of 81:18 on the coating surface. The morphology of the ceramic coatings after the calcination was also different. The coatings calcined in argon were fined: the grains and pores were smaller than those of the coatings calcined in air. The weight gains of both coatings changed in the form of parabola law, and the weight gains of the coated samples treated in argon were comparatively lower than that of the as-coated samples. During the high temperature calcination, the samples treated in argon cannot distort easily, compared with the as-coated ones.

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