Thin Film Morphology and Tribology Study in a Compliant Contact

作者：Yating Huang, Yongbao Wei, Lifei Zhang, Yongquan Xiao, Cleusia Saraiva, Zhihua Pang, Caixia Zhang · 发表于：Biosurface and Biotribology · 年份：2025 · DOI：10.1049/bsb2.70014 · 被引用次数：3 · 研究领域：Temporomandibular Joint Disorders、Dysphagia Assessment and Management、Advanced Sensor and Energy Harvesting Materials

ABSTRACT Sensory properties of food, such as creaminess and smoothness, enhance the overall consumption experience. These properties are also linked to swallowing difficulties in elderly individuals. The direct characterisation of lubrication under soft oral conditions remains a challenge. In this study, relative optical interference intensity (ROII) technique was employed to measure the lubrication film thickness under compliant contact with improved image processing to correct the accuracy loss due to the interface's low reflectivity. Interferogram analysis revealed that oil exhibited a hydrodynamic lubrication state at a low entrainment speed. The minimum film thickness occurred near the edge of the contact zone. The whey protein isolate (WPI) reached to a soft‐elastohydrodynamic state until the entrainment speed exceeded 7.5 mm/s. The variation in the Stribeck curve was influenced by the shape of the soft contacts. Both oil and WPI exhibited the state of soft‐elastohydrodynamic lubrication when a compliant PDMS pin slid on a rigid steel disc, consistent with the film thickness measurements. When a rigid steel ball slid on a PDMS pad, the hydrodynamic state was delayed. These findings provide new insights into the in vitro development of oral soft friction and enhance our understanding of oral sensory perception.