Foreign Object Damage Phenomenon by Steel Ball Projectiles in a SiC/SiC Ceramic Matrix Composite at Ambient and Elevated Temperatures

Abstract

Foreign object damage (FOD) phenomenon of a gas‐turbine grade SiC/SiC ceramic matrix composite (CMC) was determined at 25° and 1316°C using impact velocities ranging from 115 to 440 m/s by 1.59‐mm diameter steel ball projectiles. Two types of target‐specimen support were employed at each temperature: fully supported and partially supported. For a given temperature, the degree of impact damage increased with increasing impact velocity, and was greater in partial support than in full support. The elevated‐temperature FOD resistance of the composite, particularly in partial support at higher impact velocities ≥350 m/s, was significantly less than the ambient‐temperature counterpart, attributed to a weakening effect of the composite. In full support, frontal contact stresses played a major role in generating composite damage; whereas, in partial support both frontal contact and backside tensile stresses were combined sources of damage generation. Formation of cone cracks initiating from impact site was also one of the key damage features. The SiC/SiC composite was able to survive higher energy impacts without complete structural failure, as compared with gas‐turbine grade AS800 and SN282 monolithic silicon nitrides.

Erosive Wear Mechanism of New SiC/SiC Composites by Solid Particles

“…Considerable effort has been expended develop methods for evaluating silicon carbide (SiC) or erosion-related ceramic and ceramic composite materials used in engineering components in such applications as gas turbine parts, sealing bearings, and burner parts [42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58]. These applications may involve solid-particle impact and erosive wear, and it is therefore necessary to have some knowledge of behaviours and mechanisms before the materials can be used with confidence.…”

“…These applications may involve solid-particle impact and erosive wear, and it is therefore necessary to have some knowledge of behaviours and mechanisms before the materials can be used with confidence. However, most studies have focused on particulate composites, and recently little research has been carried out on advanced fibre-reinforced SiC/SiC composites, particularly with regards to impact and erosive wear [41,[55][56][57][58]. Continuous SiC fibre-reinforced SiC matrix (SiC f /SiC) composites are a promising candidate for a structural application, particularly under extreme conditions, such as high temperature and wear-resistant environments [55][56][57][58][59][60][61][62][63][64][65][66][67].…”

STUDY OF EROSIVE WEAR BEHAVIOUR ONSIC/SICCOMPOSITES

“…Composite is sometimes the only and inevitable choice to answer the purpose, due mainly to the brittle nature of ceramics [1][2][3][4][5][6][7][8][9][10] well-known as fracture mechanisms subjected to most of wear contacts, especially under sliding 1-2 and erosion [3][4][5][6] . In addition, the impact performances of monolithic SiC ceramics and SiC/SiC composites in the range of impact energy of 0.05 J to 0.0067 J clearly show not only the limitation of monolithic but also strongly supports the greatest needs of composites for the structural applications 7 ( Fig.…”

“…1). SiC/SiC composites manufactured by the route of the CVI and the LPS, both commercially available, were evaluated in order to clarify a crucial fabrication factor for average 500 μm of FOD damages 3-7 compared to the above mentioned impact assessment 7,9 . Erosive wear behaviours of the CVI and the LPS composites depicted in Figure 2 evidently show that the crucial fabrication factor against SPE is that the strength of the matrix rather than the other constituents of composites, namely, fibre bundles and PyC interfaces.…”

“…SiC fibrereinforced SiC matrix (SiC/SiC) composite is one of the cutting edges of material science, which perfectly meets the constant demands of superior material in the nuclear energy system and the aerospace propulsion system regarding energy science [1][2][3][4][5][6][7][8][9] . Wear is one of significantly important phenomena to control for the higher durability and reliability of mechanical components [1][2][3][4][5][6][7] .…”