Final rept.,FKramer,Irvin R. ;DAAG46-70-C-0102, ARPA Order- 188AMMRCCR-71-2/6(*aluminum alloys, crack propagation), (*titanium alloys, crack propagation), (*steel, crack propagation), (*crack propagation, metals), stresses, fatigue(mechanics), surface properties, vanadium alloys, deformationaluminum alloy 2014, plastic deformation, steel 4130, titanium alloy 6al 4vThe crack propagation of 2014-T6 aluminum, titanium (6Al-4V), and 4130 steel (YS = 180,000 psi) was measured under plane stress and plane strain, and a comparison was made to determine the effect of eliminating or decreasing the surface layer on the cracking resistance of the specimens. It was also shown that when specimens of 2014-T6 aluminum, titanium (6Al-4V), and 4130 steel were fatigued, the surface-layer stress increased. The number of cycles required to initiate a propagating crack was determined.
