Comparison of thermal deformations of carbon fiber-reinforced phenolic matrix ablators by arc-plasma wind tunnel heating and quasi-static heating

Abstract

Thermal deformation mechanisms of ablators were elucidated using two types of different pore-size materials under quasi-static heating (QS) conditions. When the material has small pores (Material 1), large expansion in the thickness at temperatures higher than 500°C occurred by buckling of fiber bundles caused by mismatch strain between the fiber and matrix when the matrix shrunk. In contrast, when large pores are included in the matrix (Material 2), the cracking in the matrix relaxed the mismatch strain and suppressed the buckling. Next, the deformation of Material 1 after arc-plasma wind tunnel heating (AP) tests was examined to identify the causes of thermal deformation. In this environment, expansion also occurred. However, in addition to the fiber bundle buckling, delamination leads to larger expansion than that in QS. The temperature generating expansion in AP tests was higher than that in QS tests. This behavior is caused by reaction rate slower than rapid heating rate.

Design of New Carbon-Phenolic Ablators: Manufacturing, Plasma Wind Tunnel Tests and Finite Element Model Rebuilding

“…Four points bending tests provided information about the mechanical properties and enlighten an higher stiffness and strength for the RF samples. The PWT tests, conducted in the DLR facility at different heat fluxes, show that these ablators are adequate for the exposure at an heating flux of 6 MW/m 2 guarantying an important fall of temperature of more than 2400 °C from the exposed surface to the back of the samples, considering a total thickness of 4 cm and an exposure time of about 30 s, which is a performance comparable to the more common carbon-phenolic ablators like PICA, ASTERM or ZURAM [9,46,[61][62][63]. A comparison of the Sapienza Ablative Material with these well-known ablators is proposed in Table 7 showing comparable performance when tested at 6 MW/m 2 , according to literature data.…”

Experimental system and method of aerobic thermal environment simulation based on laser heating

“…There are challenges in observing the heating morphology of the specimen because quartz lamps can block the surface of the specimen when heated. Arc wind tunnel heating 16 offers an effective means to simulate diverse aerodynamic heating test environments. However, the substantial cost associated with large-scale wind tunnel experimental equipment, along with high operational and maintenance expenses, restricts its utilisation primarily to experimental research involving large-scale structural components.…”

Thermal plasticity deformation buckling analysis on the carbon fiber-reinforced aluminum matrix composite material

“…Nevertheless, the pilot holes have destroyed the structure integrity and caused the stress concentration of connecting structures to reduce the connection strength and fatigue life of the structures. As the composite materials are more and more applied in the primary load-carrying structure of aircraft, composite materials and the fatigue-resistant manufacturing have been widely concerned 1 .…”