MODIFIED SiC-MoSi2 OXIDATION PROTECTIVE COATING FOR SiC-COATED CARBON/CARBON COMPOSITES THROUGH INFILTRATING LIQUID Si

To improve the oxidation resistance of the SiC-MoSi2 coating prepared by two-step pack cementation, a liquid Si infiltrating method was adopted to modify it. The phase composition and microstructure of the coatings were analyzed by XRD and SEM. The results show that the size and number of the cracks in the modified coating decreased evidently after infiltrating Si . The oxidation test results in air at 1773 K show that the mass loss of the SiC-MoSi2 coating coated carbon/carbon (C/C) composites was up to 1.18% after oxidation for 206 h, while that of the modified coating coated C/C composites was only 0.77% after oxidation for 460 h. The reason is that the cracks formed in the pack cementation process were partly sealed and there were no penetrable cracks in the modified coating. Therefore, there were no direct channels for the oxygen to diffuse into the C/C substrate.

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Mo–Si–B ALLOYS OXIDATION PROTECTIVE COATING FOR SiC-COATED CARBON/CARBON COMPOSITES

Surface Review and Letters ◽

10.1142/s0218625x09012524 ◽

2009 ◽

Vol 16 (02) ◽

pp. 223-229 ◽

Cited By ~ 4

Author(s):

TAO FENG ◽

HE-JUN LI ◽

QIAN-GANG FU ◽

XIAO-HONG SHI ◽

KE-ZHI LI

Keyword(s):

Weight Loss ◽

Oxidation Resistance ◽

Double Layer ◽

Protective Coating ◽

Argon Atmosphere ◽

Intermediate Temperature ◽

Carbon Composites ◽

Glass Film ◽

Coated Carbon ◽

Layer Coating

A novel Mo – Si – B double-layer coating was prepared for the carbon/carbon ( C / C ) composites by pack cementation in an argon atmosphere. The structures of the double-layer coatings were characterized by XRD and SEM. The as-received coating shows an excellent oxidation resistance at high and intermediate temperature. It could effectively protect C / C composites from oxidation for 30 h with a weight loss of 0.9% in air at 1873 K, and for 25 h with a weight loss of l.7% at 1173 K. The oxidation protective coating was principally due to producing eutectic glass film for decreasing oxygen diffusing through the penetrable cracks in the coating.

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ZrSiO4/SiC Oxidation Protective Coating for Carbon/Carbon Composites Prepared by Hydrothermal Electrophoretic Deposition

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1070 ◽

2012 ◽

Vol 512-515 ◽

pp. 1070-1073 ◽

Cited By ~ 3

Author(s):

Jia Liu ◽

Jian Feng Huang ◽

Li Yun Cao ◽

Yu Xin

Keyword(s):

Phase Composition ◽

Oxidation Resistance ◽

Cross Section ◽

Electrophoretic Deposition ◽

Protective Coating ◽

Loss Rate ◽

Deposition Process ◽

Carbon Composites

In order to improve the oxidation resistance of carbon/carbon (C/C) composites, a ZrSiO4coating on SiC pre-coated C/C composites was prepared by a hydrothermal electrophoretic deposition process. The phase composition, surface and cross-section microstructure, anti-oxidation property of the as-prepared ZrSiO4/SiC coating was investigated. Results show that hydrothermal electrophoretic deposition is an effective route to achieve crack-free ZrSiO4 outer coatings. The ZrSiO4/SiC coating can protect C/C composites from oxidation at 1773 K for 332 h with a weigh loss rate of only 4.83×10-5g/cm2·h.

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Formation and Oxidation Resistance of NbSi2 Coatings on Niobium by Pack Cementation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.280-283.907 ◽

2007 ◽

Vol 280-283 ◽

pp. 907-910 ◽

Cited By ~ 1

Author(s):

Ming Li ◽

Lixin Song ◽

Jun Le ◽

Xiao Wei Zhang ◽

Bao Gen Pei ◽

...

Keyword(s):

Phase Composition ◽

Oxidation Resistance ◽

Single Phase ◽

Element Distribution ◽

Pack Cementation ◽

Cross Sectional ◽

Pure Niobium ◽

Before And After ◽

Pack Cementation Process

NbSi2 coatings were formed on niobium by halide-activated pack cementation process. The as-coated niobium samples were oxidized in air up to 1723 K by thermogravimetry method. The surface and cross-sectional morphology, phase composition and element distribution of the NbSi2 coatings before and after oxidation were characterized by SEM, XRD and EPMA. The results show that the as-formed coatings consist of single phase of hexagonal NbSi2 and the oxidation resistance of pure niobium can be greatly improved by pack siliconizing.

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Improvement of Oxidation Resistance of Inconel 600 Alloy by Pack Cementation Process

International Journal of Advancements in Technology ◽

10.4172/0976-4860.1000208 ◽

2018 ◽

Vol 09 (03) ◽

Author(s):

Israa A Alkadir ◽

Mustafa Nash at Jawhar

Keyword(s):

Oxidation Resistance ◽

Pack Cementation ◽

Inconel 600 ◽

Inconel 600 Alloy ◽

Pack Cementation Process

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TaSi2 Oxidation Protective Coating for SiC Coated Carbon/Carbon Composites

Rare Metal Materials and Engineering ◽

10.1016/s1875-5372(11)60024-6 ◽

2011 ◽

Vol 40 (3) ◽

pp. 403-406 ◽

Cited By ~ 12

Author(s):

Shi Xiaohong ◽

Zeng Xierong ◽

Li Hejun ◽

Fu Qiangang ◽

Zou Jizhao

Keyword(s):

Protective Coating ◽

Carbon Composites ◽

Coated Carbon

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THE INFLUENCE OF SiC COATING PROCESS ON THE PROPERTIES OF C/C COMPOSITES

Surface Review and Letters ◽

10.1142/s0218625x07010317 ◽

2007 ◽

Vol 14 (04) ◽

pp. 817-820

Author(s):

MIN HUANG ◽

KE-ZHI LI ◽

HE-JUN LI ◽

QIAN-GANG FU ◽

GUO-DONG SUN

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Failure Mode ◽

Flexural Modulus ◽

Pack Cementation ◽

Bending Test ◽

Carbon Composites ◽

Coating Process ◽

Three Point Bending ◽

Coated Carbon

SiC coating for carbon/carbon composites was prepared by pack cementation method. The effects of coating process on the microstructure and the mechanical properties of C / C composites were analyzed by SEM and three-point bending test, respectively. As the infiltrated Si improved the interfaces bonding during the coating process, the flexural strength and flexural modulus of SiC -coated carbon/carbon composites were both increased by about 10% than the naked C / C composites. In addition, the mechanism of the change of failure mode of SiC coated C / C composites and naked C / C composites was addressed.

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