Creep in interlaminar shear of an Hi-Nicalon™/SiC–B₄C composite at 1300℃ in air and in steam

Abstract

Creep behavior in interlaminar shear of an advanced SiC/SiC composite with a self-healing matrix was investigated at 1300℃ in laboratory air and in steam. The composite was processed via chemical vapor infiltration (CVI). The composite has a self-healing oxidation-inhibited matrix comprising alternating layers of silicon carbide and boron carbide and is reinforced with laminated woven Hi-Nicalon™ fibers. Fiber preforms were coated with pyrolytic carbon followed by a boron carbon overlay. The interlaminar shear properties were evaluated at 1300℃. The creep behavior was examined for interlaminar shear stresses ranging from 13 to 20 MPa in air and in steam. Primary and secondary creep regimes were observed in all tests conducted in air and in steam. Creep run-out (defined as 100 h at creep stress) was achieved at 13 MPa in air and in steam. Presence of steam had little influence on creep strain rates and creep lifetimes. However, larger creep strains were accumulated in steam than in air. The retained properties of all specimens that achieved creep run-out were characterized. Composite microstructure and damage and failure mechanisms were investigated.

The anti‐oxidation mechanism of SiCf/SiC–B4C modified with Al2O3 in wet atmosphere based on machine learning

“…However, a large amount of water vapor (15–20 vol.%) 2 would be produced in the operation of aircraft engine due to the hydrocarbon combustion. In this situation, the self‐healing glass phase B 2 O 3 and SiO 2 , especially B 2 O 3 , will be volatilized because the water vapor damages the network structure of glass phase, decreasing the service life of SiC f /SiC–B 4 C self‐healing composites 4–7 . Therefore, it is necessary to improve the oxidation resistance of these composites by improving the stability of self‐healing glass phase (B 2 O 3 and SiO 2 ) under water vapor atmosphere.…”

Machine learning and a computational fluid dynamic approach to estimate phase composition of chemical vapor deposition boron carbide

“…Ceramic matrix composites (CMC) are ideal hightemperature materials because of their high-temperature resistance, wear resistance, low thermal conductivity, prevent further oxidation [5][6][7][8][9], it is a good candidate for oxidation protective materials, and it is usually added to modify the interface and matrix of CMC.…”

Machine learning and a computational fluid dynamic approach to estimate phase composition of chemical vapor deposition boron carbide

“…The common material systems of CMC are carbon fiber-reinforced silicon carbide ceramic matrix composite ,carbon fiber-reinforced carbon ceramic matrix composite and silicon carbide fiber-reinforced silicon carbide ceramic matrix composite (Cf/SiC , Cf/C and SiCf/SiC) [3,4]. Because boron carbide (BxC) can react with oxygen to generate boron oxide glass phase (B2O3, HBO3 and H3BO3) and then seal cracks to prevent further oxidation [5][6][7][8][9], it is a good candidate for oxidation protective materials, and it is usually added to modify the interface and matrix of CMC.…”