Quantifying microstructurally small fatigue crack growth in an aluminum alloy using a silicon-rubber replica method

A variation of the replica method is presented for quantifying microstructurally small fatigue crack growth rates in a rolled aluminum alloy. Repliset®, a two-part silicon-rubber compound, was employed to make surface impressions on notched specimens subjected to interrupted cyclic loading. Employing the high resolution capability of the scanning electron microscope, this replication method characterized fatigue crack growth rates of the 7075-T651 aluminum alloy for cracks as small as 10 μm in length.

► A novel method for generating small fatigue crack growth data was developed.
► Crack rates were measured on notched specimens subjected to cyclic loading.
► This method can capture crack growth from cracks as small as 10 μm.