Experiment and FEM study of one-way mixing of elastic waves with quadratic nonlinearity

•The mixing waveforms change clearly as frequency deviation increases.•The critical limit of frequency deviation for aluminum is obtained within ±7%±7%.•Received amplitude of mixing wave increases with increasing mixing distance from experiments.•A special angle of mixing wave from FEM decreases linearly with increasing mixing distance.

This paper investigates frequency deviation during imperfect resonant conditions through FEM simulations and experimental measurements using a one-way mixing technique. Waveforms of resonant waves are determined to change significantly from a diamond shape to certain toneburst trains as frequency deviation increases. The critical limit of frequency deviation for aluminum is obtained within ±7%. In the case of quasi-collinear mixing, scanning experimental results show that the received amplitude of the mixing wave increases with increasing mixing distance, and a special angle of the mixing wave in FEM simulations is found to explain this trend.