INVESTIGATION OF PLANE-BENDING FATIGUE BEHAVIOR OF 1100-H14 ALUMINUM ALLOY

Abstract

In this study, the high-cycle fatigue behavior of aluminum 1100-H14 alloy has been investigated. The main purpose of this study is the investigation of the effects of the rolling direction on tensile and plane-bending fatigue properties at room temperature. A cantilever plane-bending test machine was specially designed and manufactured for this purpose. Aluminum plates were cut in longitudinal and transverse orientations to the rolling direction. The fatigue tests using different deflection amplitudes were conducted under deflection-control and fully-reversed loading (R=-1). Tests were continued up to 107 cycles to obtain S-N curves for aluminum alloy plates. Besides the fatigue tests, in addition tensile tests were performed to determine the mechanical properties of the specimens. As a result, it was observed that tensile strength and yield strength are affected by rolling direction in 2% of average at the room temperature. However, the effect of rolling direction on fatigue strength is greater than 30% in low-cycle region, while decreased nearly zero in high-cycle fatigue region. With respect to the results of the fatigue tests in high-cycle region (HCF, approximate to 10(7)), the reduction of fatigue traces, similarity of the micro-structure and stable growth direction of the samples of the different texture structures show that the fatigue strength does not affected by the rolling direction. According to results, 1100-H14 aluminum is recommended for use in low cycle region and designs in which are not required to have high fatigue strength. Also, to help the designers of the practical applications, empirical formulas were given between the tensile and fatigue strengths.