Abstract
The process of stress-strain nonlinear deformation is fundamental to almost all branches of science and engineering. Although the mechanical mechanisms of such process are well studied, the governing atomic processes that take place inside solids during mechanical loading remains unclear. In this work, new equations to characterize the stress-strain nonlinear deformation from entropy changes on surface wetting are presented. The evolution of entropy changes during mechanical loading is calculated based on the Born-Oppenheimer approximation, wherein electronic, nuclear, electron-phonon, and phonon-phonon coupling interactions are treated independently. Further measurement and modelling of water contact angles at different strain loadings for NiTi, steel, and aluminum systems, within the elastic and the early plastic domain, are performed to validate the derived equation. These results may enable a paradigm shift from energy-force to entropy-centric research while offering exciting possibilities in NDT inspection, featureless fluid navigation, and anti-biofouling fields.
This research introduced a new mechano-wetting model, by considering Young's modulus as a linear function of strain and using the Born-Oppenheimer approach, that agreed with the experimental elastic/plastic deformation data of several bulk alloys. Subsequently, the surface entropy could be qualitatively measured and a new engineering technique to improve water collection from moist air was developed. [Display omitted]
•A derived theory relating surface wettability to mechanical straining using the Born-Oppenheimer approximation approach.•Young’s modulus is regarded as a non-linear function of tensile strain based on defect formation and entropy wetting model.•Report new equation to model surface entropy changes through surface wetting as a function of applied tensile strain.•First experimental report validating the entropy-wetting model in nonlinear stress-strain range on the surfaces of alloys.