Fatigue Performance of 2017-T4 AL. alloy Under sub-zero Temperature by Using Electromechanical Freezing System

Abstract

The effects of sub-zero(-22C o ) cyclic rotating bending on the S-N behavior and cumulative damage are reported for 207-T4 aluminum alloy .Experimental characterization of fatigue behavior showed that the S-N curves behavior may described by the following Basquin's formulas:At room temperature (RT) And At sub-zero temperature (-22C o ) From the above equation, the fatigue behavior can be change at and . Slightly increase in fatigue life results above 204 MPa and slightly decrease in fatigue below the 204 MPa stress level. A non-linear experimental law is introduced for the accumulation of damage at sub-zero temperature variable fatigue. This law gave conservative and safe fatigue life time prediction when applying to the data of variable fatigue at low temperature (-22 C o ).