Effect of Moisture Absorption on Hot/Wet Compressive Strength of T800HIPMR-15 Carbon/Polyimide

Abstract

The objective of this study is to statistically investigate the effect of moisture absorption on the hot/wet compressive strength of a T800H/PMR-15 carbon/polyimide composite with a quasi-isotropic stacking sequence. Compression tests on the moisture absorbed specimens were conducted at 260'C. These tests clarified the compression fracture mode, the effect of moisture absorption on hot/wet compressive strength, statistical properties and a design allowable of hot/wet compressive strength, the effectiveness of a traveler coupon to monitor moisture absorption, and the relationship between specimen thickness and hot/wet compressive strength. Important results are as follows: (1) hot/wet compressive strength was closely related with the residual moisture content measured immediately after the test, and (2) the coefficient of variation of hot/wet compressive strength was approximately twice as large as that of room temperature/dry compressive strength.

Keywords

carbon/polyimide moisture absorption compression tests statistical investigation hot/wet compressive strength fracture modes statistical properties design allowable traveler coupon specimen thickness

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