Damping Characteristics of Cold-Worked Al–Si Alloys

Abstract

The logarithmic decrement δ, the rigidity modulus G and the tensile strength σt have been studied on Al–Si alloys containing 0–15%Si when heat-treated or subsequently cold-worked. Measurements of δ and G were carried out at a frequency of 1 Hz by an inverted torsion pendulum method, and the σt was measured using an Instron-type testing machine.The δ values of the heat-treated alloys are very small and increase with Si concentration. The δ in the furnace-cooled state is larger than that in the water-quenched state. With further cold working, the values exhibit an abrupt increase with increasing degree of working.The G and σt values of the alloys in the heat-treated state increase with Si concentration. The G and σt show large values when furnace-cooled and water-quenched, respectively. With further cold working, the G decreases and the σt increases.