Mechanical description of interfacial slips for quartz crystal microbalances with viscoelasticliquid loading

Abstract

Acoustic wave devices, such as quartz crystal microbalances (QCM), are extended toapplications in liquid environments. An interfacial slip phenomenon is expected to occur atthe interface between the surface of a quartz crystal sensor and the contactedliquid environment. Assumptions of continuous displacement and stress at theliquid–solid interface mask the physical details of the contact interface. In thispaper, the motion equations of the interfacial particles are employed to replace theinterfacial continuous displacement and continuous stress assumptions. The electricalimpedance of QCM in the liquid environment is derived based on this proposedmodeling. The comparison of the present result with that of the continuous stress anddisplacement model is presented. The slip parameter, which is defined as theamount of displacement transmission between the quartz crystal top surface andbottom liquid particles, is presented as a function of the contact properties. Theeffects of interactive force strength, liquid viscosity and attached-particles sizeare included in the numerical studies. The detailed modeling of the interface isuseful in interpreting the slip phenomenon between the sensor surface and theliquid.