High Temperature Oxidation Behaviors of CNTs/MoSi2 Composites

Molybdenum disilicide (MoSi2) matrix composites with various contents of carbon nanotubes (CNTs) were fabricated by sintering in vacuum at 1550°C for 1 h. The oxidation behaviors of CNTs/MoSi2composites at 1300°C for 200 h in air were studied. Results showed that MoSi2matrix composites with no more than 8 % CNTs in volume had good oxidation resistance at 1300 °C, although addition of CNTs reduced the high temperature oxidation resistance of MoSi2. An approximate linear relationship was found between the weight gain of CNTs/MoSi2composites and the content of CNTs. The oxidation resistance of CNTs/MoSi2composites at high temperature decreased with the increasing of CNTs contents. Since the gaseous products were formed during the oxidation process and escaped from the oxide film, the protective film became loose which offered channels for the oxygen soaking into the composites. Thus the oxidation resistance of CNTs/MoSi2composites was decreased.

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High-temperature oxidation resistance of VCps-reinforced Fe-matrix composites using an in-situ reaction

AIP Advances ◽

10.1063/1.5013065 ◽

2019 ◽

Vol 9 (1) ◽

pp. 015319

Author(s):

Pinghu Chen ◽

Ruiqing Li ◽

Ripeng Jiang ◽

Songsheng Zeng ◽

Yun Zhang ◽

...

Keyword(s):

High Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Matrix Composites ◽

Temperature Oxidation ◽

In Situ Reaction

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High Temperature Oxidation Behaviors of CrNx and Cr-Si-N Thin Films at 1000 °C

Coatings ◽

10.3390/coatings9090540 ◽

2019 ◽

Vol 9 (9) ◽

pp. 540 ◽

Cited By ~ 4

Author(s):

Bih-Show Lou ◽

Yue-Chyuan Chang ◽

Jyh-Wei Lee

Keyword(s):

Thin Films ◽

High Temperature ◽

Oxide Layer ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Temperature Oxidation ◽

X Ray ◽

Oxidation Test ◽

Parabolic Rate ◽

Oxidation Behaviors

The high temperature oxidation performance of nitride thin films has become an important issue when they are used as protective coatings on dry cutting tools or on die casting molds. In this study, the high temperature oxidation behaviors of CrNx and Cr-Si-N thin films were investigated at 1000 °C for 6 h in ambient air. The CrNx and Cr-Si-N thin films were prepared by a bipolar asymmetric pulsed direct-current (DC) magnetron sputtering system. Cr-Si-N films with silicon content ranging from 3.9 to 12.2 at.% were deposited by adjusting the Si target power. A thermogravimeter was adopted to study the oxidation kinetics of thin films. The weight gains were measured to calculate the parabolic rate constants of thin films. X-ray diffraction, X-ray mapping, and Auger electron spectroscopy were employed to study the microstructure and elemental redistributions of oxidized thin films. The as-deposited CrNx and Cr-Si-N thin films consisted of CrN and Cr2N mixed phases. The faceted Cr2O3 surface oxides, porous inner oxide layer, and oxygen-containing CrSi2 phases were found for the CrN film after oxidation test. On the other hand, the Cr-Si-N film containing 12.2 at.% Si showed a dense surface oxide layer and a thick and compact nitride layer, which indicates its best oxidation resistance. The high temperature oxidation resistance of Cr-Si-N thin films was improved by increasing Si content, due to the amorphous matrix contained nanocomposite microstructure and the formation of amorphous silicon oxide to retard the diffusion paths of oxygen, chromium, silicon, and nitrogen. The lowest parabolic rate constant of 1.48 × 10–2 mg2/cm4/h was obtained for the 12.2 at.% Si contained Cr-Si-N thin films, which provided the best oxidation resistance at 1000 °C for 6 h in this work. It should be noted that the residual tensile stress of thin film had a detrimental effect on the adhesion property during the oxidation test.

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High-temperature oxidation resistance of a Ti–Al–Sn–Zr titanium matrix composites reinforced with in situ TiC and Ti5Si3 fabricated by powder metallurgy

Applied Physics A ◽

10.1007/s00339-020-3431-x ◽

2020 ◽

Vol 126 (4) ◽

Author(s):

Xiaojing Xu ◽

Yangguang Liu ◽

Vitus Tabie ◽

Chengbin Cai ◽

Yishui Xiao ◽

...

Keyword(s):

High Temperature ◽

Powder Metallurgy ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Matrix Composites ◽

Titanium Matrix ◽

Titanium Matrix Composites ◽

Temperature Oxidation ◽

In Situ Tic

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Effect of Al Content on the High-Temperature Oxidation Resistance and Structure of CrAl Coatings

Coatings ◽

10.3390/coatings11121434 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1434

Author(s):

Jiaojiao Ma ◽

Chuiyi Meng ◽

Hui Wang ◽

Xiujie He

Keyword(s):

High Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Harmful Effect ◽

Antioxidant Properties ◽

Oxidation Mechanism ◽

Oxide Thickness ◽

Temperature Oxidation ◽

Al Content ◽

Oxidation Behaviors

The oxidation behaviors of Cr, Cr93.4Al6.6, Cr58.1Al41.9, and Cr34.5Al65.5 coatings, deposited by using multi-arc ion plating technology, at high temperature were studied. The weight gain, oxide thickness, morphology, and phase composition of the coatings before and after oxidation were analyzed in detail. The results show that there is an Al content window available for tuning the oxidation behaviors of the CrAl-based coatings. The Cr93.4Al6.6 coating is considered to be most protective and can effectively improve the high-temperature oxidation resistance of the substrate; whereas, too high an Al content has a harmful effect on the antioxidant properties of the coatings. The oxidation mechanism of Cr and CrAl coatings were also discussed.

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High-Temperature Oxidation Resistance of Ceramic Matrix Composites Si3N4– Cf

Powder Metallurgy and Metal Ceramics ◽

10.1023/b:pmmc.0000022198.62350.74 ◽

2003 ◽

Vol 42 (11/12) ◽

pp. 592-595 ◽

Cited By ~ 3

Author(s):

Irina Yu. Kelina ◽

Larisa A. Plyasunkova ◽

Lyudmila A. Chevykalova

Keyword(s):

High Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Ceramic Matrix Composites ◽

Ceramic Matrix ◽

Matrix Composites ◽

Temperature Oxidation

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High Temperature Oxidation of Electroplated Cr-C Coating

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.418 ◽

2006 ◽

Vol 510-511 ◽

pp. 418-421 ◽

Cited By ~ 1

Author(s):

Dong Bok Lee ◽

Sik Chol Kwon

Keyword(s):

High Temperature ◽

Oxidation Resistance ◽

High Temperature Oxidation ◽

Microcrystalline Structure ◽

Temperature Oxidation ◽

Good Oxidation Resistance

The oxidation of Cr-12.7 at.%C coatings electrodeposited on steel was studied at 700 and 800oC in air. The coatings, which consisted of nodular grains having microcracks and pits, had either an amorphous or a microcrystalline structure. They changed to crystalline Cr during oxidation. The oxidation resulted in the formation of Cr2O3, which provided good oxidation resistance to the coating. However, the presence of microcracks and pits in the coating was harmful to oxidation resistance.

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Tribology and high-temperature oxidation behaviors of NiCrBSiFe composite coatings on Ti6Al4V alloy by laser cladding

RSC Advances ◽

10.1039/c5ra14732h ◽

2015 ◽

Vol 5 (93) ◽

pp. 76516-76525 ◽

Cited By ~ 5

Author(s):

Peng-Cheng Yu ◽

Xiu-Bo Liu ◽

Xiao-Long Lu ◽

Shi-Jie Qiao ◽

Yong-Jie Zhai ◽

...

Keyword(s):

High Temperature ◽

Oxidation Resistance ◽

Laser Cladding ◽

High Temperature Oxidation ◽

Composite Coatings ◽

Ti6al4v Alloy ◽

Temperature Oxidation ◽

High Temperature Wear ◽

Oxidation Behaviors

In order to improve the high-temperature wear and oxidation resistance of Ti6Al4V alloys simultaneously, NiCrBSiFe composite coatings were deposited on a Ti6Al4V alloy by laser cladding.

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Phase transformation and layer evolution in molybdenum disilicide-silicon carbide nanolayered coatings

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170426 ◽

1994 ◽

Vol 52 ◽

pp. 538-539

Author(s):

H. Kung ◽

T. R. Jervis ◽

J.-P. Hirvonen ◽

M. Nastasi ◽

T. E. Mitchell ◽

...

Keyword(s):

Phase Transformation ◽

High Temperature ◽

Oxidation Resistance ◽

Elevated Temperatures ◽

Matrix Material ◽

Molybdenum Disilicide ◽

High Temperature Strength ◽

Cross Sectional ◽

Good Oxidation Resistance ◽

Structural Applications

MoSi2 is a potential matrix material for high temperature structural composites due to its high melting temperature and good oxidation resistance at elevated temperatures. The two major drawbacksfor structural applications are inadequate high temperature strength and poor low temperature ductility. The search for appropriate composite additions has been the focus of extensive investigations in recent years. The addition of SiC in a nanolayered configuration was shown to exhibit superior oxidation resistance and significant hardness increase through annealing at 500°C. One potential application of MoSi2- SiC multilayers is for high temperature coatings, where structural stability ofthe layering is of major concern. In this study, we have systematically investigated both the evolution of phases and the stability of layers by varying the heat treating conditions.Alternating layers of MoSi2 and SiC were synthesized by DC-magnetron and rf-diode sputtering respectively. Cross-sectional transmission electron microscopy (XTEM) was used to examine three distinct reactions in the specimens when exposed to different annealing conditions: crystallization and phase transformation of MoSi2, crystallization of SiC, and spheroidization of the layer structures.

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