Measurement of residual stress in quenched 1045 steel by the nanoindentation method

In this paper, the residual stress in quenched AISI 1045 steel was measured by a recently developed nanoindentation technique. Depth control mode was adopted to measure the residual stress. It was found that residual compressive stress was generated in the quenched steel. The material around nanoindents exhibits significant pile-up deformation. A new method was proposed to determine the real contact area for pile-up material on the basis of invariant pile-up morphology of the loaded or unloaded states. The results obtained by the new method were in good agreement with the residual stresses measured by the classical X-ray diffraction (XRD) method.

Research Highlights
► A new method was proposed to measure the real contact area for pile-up materials.
► The real contact depth is defined as the sum of hmax and the pile-up height hp.
► The value of residual stress measured by the nanoindentation method was in good agreement with that by the XRD method.