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Accurate evaluation of the elastic modulus of thermal-sprayed coatings is very important to ensure the safety and durability of industrial components, but it seems difficult via conventional technique. Although indentation technique is available to estimate the local modulus of coatings, it does not reflect the effects of porosity or cracks. Impulse excitation technology (IET) is a simple and accurate method to evaluate the elastic modulus of bulk materials. It was used to determine the modulus of thermal-sprayed coatings via relative method in this work. An analytical relationship among the moduli of the coating, the substrate and the coating/substrate system was derived. Thus, the modulus of coatings was obtained via the measured modulus of the samples before and after coating. Experiments on Q235 steels coated with NiCr coatings, were carried out to investigate the effect of atomization gases on the elastic modulus of NiCr coatings. The results indicated that the elastic modulus of NiCr coating prepared by air atomization (NiCr-Air) was higher than that of NiCr coating prepared by N2 gas atomization (NiCr-N2). The reasons for this were the formation of Ni(Cr2O4) reinforced NiCr alloy laminated composite, and the laminated composite structure had a positive influence on the elastic modulus.