Paper number 191

CHARACTERISATION OF OVEN CURED PMC RADOME PANEL FOR AIR BORNE APPLICATION

Niranjanappa A.C.¹, and Dwarakadasa E.S.²

1 Centre for Air Borne Systems, Defence Research & Development Organisation
Yemalur PO., Bangalore - 560 037, India
2 Structure Property Correlation Group, Department of Metallurgy,
Indian Institute of Science, Bangalore - 560 012, India

Summary

In radome manufacturing, prepregs (pre-impregnated composites), which contain the required amount of resin (B-stage) in the fabric are more popular, because they offer ease of handling, better resin control and dimensional tolerance [1]. For curing of prepregs, autoclave is recommended to obtain uniform resin flow and better compaction. However, due to certain reasons, use of an oven for curing of a high technology large size airborne radome was necessitated. Curing is a critical operation in obtaining the optimum properties in the material for a radome. Due to the change in curing from autoclave to oven, there was a need for establishing the most suitable cure cycle for oven curing. In this paper the characterisation process performed to achieve the optimum oven cure cycle has been presented. Both destructive and non-destructive tests have been carried out to assess the properties of cured components. Samples cured in different cure cycles were tested as per ASTM standards [2] and results compared with the properties of an autoclave cured reference sample. Based on this characterisation process one cure cycle, which gave properties close to those of autoclave cured sample has been selected for the application.

Keywords

autoclave, C-Scan, cure cycle, drum peel, fexural strength, ILSS, oven, radome, sandwich.