Dislocation Density-Based Finite Element Method Modeling of Ultrasonic Consolidation

摘要: A dislocation density based constitutive model has been developed and implemented into a crystal plasticity quasi‐static finite element framework. This approach captures the statistical evolution of structures grain fragmentation at bonding interface when sufficient boundary conditions pertaining to Ultrasonic Consolidation process are prescribed. Hardening is incorporated using statistically stored geometrically necessary densities (SSDs GNDs), which analogs isotropic kinematic hardening respectively. The GND considers strain‐gradient thus renders size‐dependent. calibrated experimental data from published refereed literature then validated for Aluminum 3003 alloy. Introduction As direct result ongoing research efforts in ultrasonic consolidation (UC) worldwide [1], it become apparent that new modeling UC needed. provides better understanding effects parameter changes on refinement, plastic deformation during will enable researchers predict materials bond, how mechanical properties UC-produced parts can be improved, design next generation equipment. continuum made strongly dependent upon micromechanics bonded [1]. Interfacial-scale microstructures studied fundamentally electron microscopy [1] used correlate atomic mesoscopic mechanisms their counterparts. density-based Finite Element Model (FEM) capture distribution dislocations, partials various as inputs macroscopic profiles function energy input characteristics. These characteristics parameters machine, namely vibration amplitude, normal force, frequency, welding speed, sonotrode geometry temperature. Problem Formulation It shown material sheets subjected undergo inhomogeneous through thickness Classical theories do not fully explain this phenomenon [2]. Therefore, study strain localization refinement interfaces required. following steps lead calculation these localized strains effects. Large Deformation Quasi-Static Crystal Plasticity Description map space time described by total gradient tensor F (Figure 1). Applying Kroner-Lee assumption, decomposed elastic Fe Fp tensors multiplicative operator theory