1993 Volume 32 Issue 4 Pages 233-241
In order to investigate the damage process and its nondestructive evaluation technique in carbon／epoxy laminates，the authors applied simulataneously the AE analysis，the stress pattem analysis using infrared thermal imaging and soft X ray radiography together for circularhole notched［0°／90°］2S laminate plates subjected to monotoneously tensile and cyclically fatigue－loading． The results are summarized as follows， （1）In tensile fracture process，the AE event occurs at the stage of67％of the ultimate stress and its AE event has wide amplitude distributions different from that in cyclically fatigue－10ading． （2）The initial stage of damage process occuring during fatigue loading for a［0°／90°］2S Iaminate－plate with a circular hole shaped notch has been suggested to be the transverse laminar cracks initiated at the edge of hole notch and its propagation accommanying delamination between matrix and fibers，by using both Qf infrared thermal imaging stress analysis and AE analysis．And，the facts suggested by NDT techniques have been connrmed by Xray radiography and scaming electron microscopic observations， （3）It’s concluded that the simultaneous use of the infrared thermal imaging stress analysis and AE analysis has been proposed as a possible NDT technique for monitQring of damage process in the composite materials such as carbon／epoxy Iaminates．
