Author: G. H. Stevens Publisher: ISBN: Category : Languages : en Pages : 29
Book Description
Fatigue strength is presented of phenolic laminates 1/4, 1/8, and 1/16 inch in thickness under repeated load. Laminates were of CTL-91LB phenolic resin reinforced with 181-A1100 glass fabirc. Fatigue strength values were determined by applying axial loads parallel to the wary direction of the glass fabric reinforcement at 5, 25, and 900 cycles per minute and at mean stress levels of zero pounds per square inch, 25 and 50 percent of the compression control strength, and at 50 percent of the tension control strength. Specimens were evaluated at 73, 400, 500, 600, and 800 F. Results are presented in tables, and S-N curves (Maximum applied stress versus number of cycles to failure). (Author).
Author: George H. Stevens Publisher: ISBN: Category : Laminated plastics Languages : en Pages : 0
Book Description
This report covers fatigue tests made on representative laminates of CTL-91LD resin reinforced with 181-A1100 glass fabric. Fatigue tests with axial loads applied parallel to the warp direction and at zero mean stress were made at the rate of about five cycles per minute. Specimens were tested at room temperature (73 F.), 400, 500, 600, and 800 F. All the tests were made on a constant-load type machine and loading was to high stress levels. Starting with the average value found in the static control test, the loads were progressively lowered until a specimen would maintain the established load for about 200 cycles without failure. The specimens, with few exceptions, failed on that portion of the cycle, either in tension or compression, that had the lowest average value in the static control test. Fatigue tests at room temperature showed that at 80% of the tension-control strength, specimens would sustain about 200 cycles of repeated loading. At the elevated temperatures, however, there were no clearly indicated trends between 1 and 200 cycles because of strength-time-temperature variations. (Author).