Evaluation of creep-fatigue life and strength for AA7001-T6 under constant amplitude loading

Abstract

Aluminum alloys were widely used in the construction, automotive, marine, and aviation industries due to their low specific strength, ease of manufacture, and low weight. The fatigue behavior of aluminum alloys at different temperatures is investigated. Thanks to the rapid development of armament in recent years, 7XXX ultra-high strength aluminum alloys are now used more frequently because of their non-corrosive qualities and low weight. Aluminum alloy 7001-T6 behavior is examined at the Company State for Engineering, Rehabilitation, and Inspection (SIER) in Iraq, where chemical analysis of the AA7001 is supported. Most engineering components that operate at high temperatures will eventually fail from fatigue strain, creep damage is a time-dependent process that is primarily influenced by the history of stress and temperature applied to the component. When the two damaging factors combine their effects, This study used AA7001-T6 to conduct experiments on mechanical characteristics (UTS, YS, E, and ductility) and the interaction between creep and fatigue at four distinct temperatures: room temperature (25, 150, 280, and 330) °C, the UTS, YS, and E were lowered by 37.2, 37.2, and 24) %, respectively, as compared to the result at room temperature, but the ductility increased by 28.27 %. It has been noted that rising temperatures cause mechanical and fatigue characteristics to decline. Experimental S-N fatigue test findings showed a significant loss of fatigue strength, After 107cycles, the endurance fatigue limit was reduced from 208 MPa at (RT) to 184 MPa at 330 °C, an 11.5 % reduction. Overall, it can be said that AA7001-T6 demonstrates a significant drop in mechanical and fatigue properties at high temperatures

Identifying regularities of high temperature on constant and variable fatigue life of AA7075-Al2O3 nanocomposite fabricated by stir casting method

“…The high temperature reduced the mechanical properties, the (UTS) reduced from 233 MPa to198 MPa showing 15 % reduction percentage while the Al 2 O 3 improved (UTS) from 198 MPa to 236 MPa showing 16 % improvement and 15.7 % enhancement for (YS) at (150 °C), The same results were found by [6,8]. The improvement in the mechanical properties of the 6 wt % nanocomposite may be related to the less amount of porosity and uniformly distributed of nanocomposite into the matrix [8].…”

“…The paper [8] examined the fatigue properties of metal alloys at a variety of temperatures and discovered that at room temperature, UTS, YS, and E were lower, but ductility increased by 28.27 %. They investigated the influence of elevated temperatures on the fatigue and tensile properties of 7001-T6 aluminum alloy.…”