My attempts at Q measurement full-wave/half-wave aluminum_properties.html Strain of 0.00155 (125 microns) - is this peak or peak-to-peak? Give test instrumentation (Clarke-Hess?) The existance of an endurance limit generally correlates with the linearity of the stress-strain curves and a sharply defined yield point. (Juvinall[1], p.ÿ201; Grosskreutz[1], p.ÿ42) If this is the case, then most aluminums should not have a fatigue limit. However, Maennig[1] indicates (p.ÿ614) that the high-strength age-hardening aluminum alloys may have a true fatigue limit (at conventional test frequencies) at 10^11 to 10^13 cycles (i.e., 1400 hours to 140,000 hours at 20 kHz) for stresses of about 20 MPa (2900 lbf/in2). Lesuer, Donald - 'Experimental Investigations of Material Models for Ti-6Al-4V Titanium and 2024-T3 Aluminum' (high strain rate tests) Fig 2 shows anisotropic 2D etched microstructure of 2024-T3. Juvinall shows fatigue graphs for 2024 (p. 272) & 7075 (p. 273) up to 10^9 cycles. Boyer (p. 335) notes that 2024 is better under fluctuating stress. Note: ultrasonic startup & decay - considered fluctuating? Should include hatch_p376__grain_directionality_in_rolled_al7075t6_1c.png? What is source of this image? Effect of temperature on modulus - See my black 3-ring binder, tab M --> cubic regression equation See Temp_A24.plt and Temp_A75.plt --> Aloco data -------------- To do -------------- 4/Dec/2017 11:48 Include data for Culp Poisson tests on large dia spool horns 20/Nov/2017 18:02 Look for Al in Ogden fatigue book. 3/22/2015 - Replace all refs to "Aerospace" aluminum.