The present work encompasses the investigation of Low Cycle Fatigue (LCF) of aluminum alloy AA6061 in three conditions, annealing (O), T4 and T651. AA6061-O has the higher value of transition fatigue life (N T ) because it has the highest ductility, while the fatigue strength exponent and fatigue ductility exponent are within the range of metallic materials. The SEM morphology for specimens at strain closer to true tensile stress show multi-crack origins with secondary cracks and large final fracture zone. The striations are very clear for O-condition.

In this paper a new mechanism for deep drawing was proposed to produce circular cup from thin plate without blank holder. In this technique the die assembly includes punch, die and die-punch. A 2D axisymmetric finite element model was built using DEFORM software. Effect of die geometry (half-cone angle) on maximum load, thickness distribution, strain distribution and effect of clearance ratio between punch and (die-punch) on the wrinkling of the cup were investigated. Three half-cone angles of die (15o, 30o and 45o) were used for forming sheet metal of brass (CuZn37) which had initial thickness of (1mm) at four clearance ratio (c/t) for die of 30o half-cone angle. Finite element model results showed good agreement with experimental results. Die of 30o half-cone angle with clearance ratio (c/t) of 0.9 gave the best product without wrinkling. The main advantage of this technique compared to the conventional deep drawing is that the circular cup can be carried out in single action press with limit drawing ratio (LDR) of 1.86 and blank diameter to blank thickness ratio (d/t) < 86.

This research involved studying the effect of shot peening, by steel balls, on Low Cycle Fatigue (LCF) of aluminum alloy AA 2024-T4 at different peening times (5, 10, 15, 20 & 30 min.). Shot peening helped to increase the tensile and yield strength (?_u, ?_y) to reach the highest values at the time of 15 minutes and then declined. Strain hardening coefficient (n) increased to some extent, which recorded an indication of the possibility of continued cyclic hardening behavior of the alloy during LCF after the peening. LCF tests showed that un-peened AA 2024-T4 was more resistant especially at rates lower than 9x10³ cycles, then for 15 min. shooting, a pronounced improvement in LCF life down to the number of cycle’s equal to10⁵ cycles. SEM showed that the size of dimples, length of secondary cracks and the voids increased for peened specimens were especially at high cyclic strains near the strains of ?_u.

Foamed asphalt refers to a bituminous mixture of road-building aggregates and foamed bitumen, produced by a cold mix process. There are a lot of related issue that has not been sufficiently investigated so far. It is worthwhile to overview the main theoretical and practical results in the field in several countries including those of the authors of the paper. It is clear that the foamed asphalt is usually characterized by high quality and reasonable cost, can be used in cold road pavement rehabilitation, in addition to it the technique is environ-mentally friendly preserving natural resources. Using foamed bitumen reduces the emissions of carbon dioxide and gases resulting from combustion, especially when it is used as a cold rehabilitation binder and mixed with re-claimed asphalt pavement materials.

This research ensured the effects of radius variation on fatigue – life of AA6061-T6 and annealed alloy, AA6061-O. Five different sizes of radius (1, 2, 4, 8, and 16) mm were studied using Neuber notch factor (Kf) instead of the theoretical stress concentration factor (Kt). The numerical modeling was adopted using ANSYS Workbench 15 to evaluate the radius size effectiveness on strain and stress distribution, while the experimental procedure carried out to determine the strain-life constants for analytical calculations. The results show that the reduction in the radius leads to increase stress, while the strain remains close to each other with the variations of radius for both alloys. The decrement in stress and strain values for annealed specimens were observed in comparison with base alloy. The transition life (NT) was decreased whenever the radius decreased in both alloys. The fatigue life of annealed specimens increased for all values of radius compared to the specimens without annealed. The comparison of the fatigue life between the experimental and numerical results shows that the experimental results have more than those obtained by numerical estimation and this indicated the validity of the numerical approach.