Ablative Materials Seminar Report

Ablative Material Seminar Report Download
Advances in aeronautics and astronautics have been closely associated with significant increases in operational temperatures. In chemical combustion systems, flame temperatures are approaching 5500°F and higher. Gas temperatures at least twice that high are being encountered in the boundary layer of hypersonic atmospheric entry vehicles. These extremely high-temperature conditions may lead to the thermal destruction of an exposed vehicle or a component unless suitable protection is provided.

Protection of a structure in a very high-temperature environment may be accomplished with ease through the use of a new class of engineering materials. These thermally protective materials are known as "ablators" or "ablative materials". They are applied to the exterior of a load-bearing structure and thereby isolate it from the hyperthermal environment. The structure is thus maintained near its initial temperature at which it exhibits optimum strength characteristics.

Ablative materials are unique in that they accommodate virtually any temperature or heat flux condition, automatically control the surface temperature, greatly restrict any internal flow of heat, and expend thousands of Btu's of energy for each pound of material. These capabilities are the result of a self-regulating, orderly, and gradual removal of exposed surface material, which takes place during the interaction of the high-temperature environment with the material.