Elasticity mapping of delta precipitate in alloy 625 using atomic force acoustic microscopy with a new approach to eliminate the influence of tip condition

We describe a novel approach to eliminate the effect of change in tip condition on mapping of elastic properties by atomic force acoustic microscopy. The method involves simultaneous acquisition of two contact resonances and using the contact stiffness of the matrix in every scan line as reference for finding the indentation modulus of fine precipitates. The methodology is demonstrated by mapping the indentation modulus of a 200 nm wide delta precipitate in a nickel-base superalloy.