Yttrium silicate coating system for oxidation protection of C/C–Si–SiC composites: Electrophoretic deposition and oxygen self-diffusion measurements

The use of carbon fibre reinforced carbon composites in oxidizing atmospheres is limited to temperatures below 400 °C. To benefit from their excellent mechanical strength that is still preserved at high temperatures, suitable oxidation protection coating systems have to be developed. Composites which are capillary infiltrated with Si and coated with SiC via chemical vapour deposition show significantly enhanced oxidation resistance. For the increase of service temperature above 1300 °C, high temperature stable materials with low oxygen diffusivities such as yttrium silicates have to complement the SiC coating. The electrophoretic deposition performed under constant current conditions leads to relatively high green densities and therefore good sinterability of the applied coatings. In this work we present the preparation of suspensions, their characterization regarding particle size and electrophoretic mobility for yttrium silicate powder prepared by the solid state method. Depending on particle charge and conductivity of the investigated suspensions iodine is employed to increase particle charge. The use of current densities between 0.5-5mA/cm² leads to smooth and homogeneous layers. Layers sintered as low as 1400 °C for 2h already show promising protection of the C/C-Si-SiC substrate during thermogravimetric analysis.

Download Full-text

Synthesis and Electrophoretic Deposition of an Yttrium Silicate Coating System for Oxidation Protection of C/C-Si-SiC Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.494.451 ◽

2005 ◽

Vol 494 ◽

pp. 451-456 ◽

Cited By ~ 5

Author(s):

Christos Argirusis ◽

Tanja Damjanović ◽

M. Stojanović ◽

Günter Borchardt

Keyword(s):

Electrophoretic Deposition ◽

Oxygen Permeability ◽

Pechini Method ◽

Yttrium Silicate ◽

Low Thermal Expansion ◽

Deposition Voltage ◽

Coating Method ◽

Sic Composites ◽

Controlled Deposition ◽

Sic Coatings

Due to favorable chemical and mechanical properties of yttrium silicate coatings (low Young’s modulus, low thermal expansion coefficient, low evaporation rate and oxygen permeability, good erosion resistance), this material is a promising complement to SiC coatings for protecting C/C-Si-SiC composites. For the preparation of silicate powders, the Pechini method was used. As a coating method, electrophoretic deposition from stable suspensions based on isopropanol was chosen. Under controlled deposition voltage and duration, coatings of various thicknesses were deposited. The deposited layers were characterized by SEM and EDX analysis. The protectiveness of these coatings was tested by isothermal thermogravimetry.

Download Full-text

Improvement of the electromagnetic shielding properties of C/SiC composites by electrophoretic deposition of carbon nanotube on carbon fibers

Carbon ◽

10.1016/j.carbon.2016.07.070 ◽

2016 ◽

Vol 109 ◽

pp. 149-153 ◽

Cited By ~ 73

Author(s):

Hui Mei ◽

Daoyang Han ◽

Shanshan Xiao ◽

Tianming Ji ◽

Jian Tang ◽

...

Keyword(s):

Carbon Nanotube ◽

Carbon Fibers ◽

Electrophoretic Deposition ◽

Electromagnetic Shielding ◽

Shielding Properties ◽

Sic Composites

Download Full-text

Effect of heat treatment on the microstructure and strength of yttrium silicate matrix-modified SiCf/SiC composites

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2021.09.031 ◽

2021 ◽

Author(s):

Fang He ◽

Yongsheng Liu ◽

Jingxin Li ◽

Binghui Zhang ◽

Ning Dong ◽

...

Keyword(s):

Heat Treatment ◽

Silicate Matrix ◽

Yttrium Silicate ◽

Sic Composites

Download Full-text

Application of Electrophoretic Deposition for Interfacial Control of High-Performance SiC Fiber-Reinforced SiC Matrix (SiCf/SiC) Composites

Nanotechnology ◽

10.4018/978-1-4666-5125-8.ch068 ◽

2014 ◽

pp. 1448-1463 ◽

Cited By ~ 1

Author(s):

Katsumi Yoshida

Keyword(s):

Mechanical Properties ◽

Electrophoretic Deposition ◽

High Performance ◽

Carbon Coating ◽

Interfacial Debonding ◽

Fabrication Process ◽

The Novel ◽

Fiber Pullout ◽

Sic Fiber ◽

Sic Composites

This chapter reviews the novel fabrication process of continuous SiCf/SiC composites based on electrophoretic deposition (EPD). EPD process is very effective for achieving relatively homogeneous carbon coating with the thickness of several tens to hundreds nanometers on SiC fibers. Carbon interface with the thickness of at least 100 nm formed by EPD acts effectively for inducing interfacial debonding and fiber pullout during fracture, and the SiCf/SiC composites show excellent mechanical properties. From these results, it is demonstrated that the fabrication process based on EPD method is expected to be an effective way to control the interfaces of SiCf/SiC composites and to obtain high-performance SiCf/SiC composites.

Download Full-text