Technical Report of National Aerospace Laboratory. Effect of Moisture Absorption on Hot/Wet Compressive Strength of T800H/PMR-15 Carbon/Polyimide

摘要

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 moisture absorbed specimens were conducted at 260 deg C. These tests clarified the compression fracture mode, the effect of moisture absorption on the hot/wet compressive strength, statistical properties and a design allowable of hot/wet compressive strength, the effectiveness of a traveler coupon in monitoring moisture absorption, and the relationship between specimen thickness and hot/wet compressive strength. Important results were as follows: (1) Hot/wet compressive strength was found to be closely related to residual moisture content measured immediately after the test, and (2) The coefficient of variation of hot/wet compressive strength was found to be approximately twice as large as that of room temperature/dry compressive strength.