Interactive dissection simulation is an important research topic in the virtual reality (VR) community. There are many efforts on this topic; however, most of them focus on building a realistic simulation system regardless of the cost, and they often require expensive workstations and specialized haptic devices which prevent broader adoption. We show how to build a realistic dissection simulation at an affordable cost, which opens up applications in elementary education for virtual dissections which are currently not feasible. In this thesis, we present a fast and robust haptic system for interactive dissection simulations of finite elements based deformable objects which supports two type of haptic interactions: point contacts and cuts. We design a semi-progressive virtual dissection scheme of deformable objects in a real-time application. The quality and performance of visual/haptic feedback is demonstrated on a low-end commercial desktop PC with a haptic device.

Semi-solid deformation mechanisms are important in a range of manufacturing and natural phenomena, which range from squeeze casting to magma flows. In this thesis, using high speed synchrotron X-ray tomography and a bespoke precision thermo-mechanical rig, a four dimensional (3D plus time) quantitative investigation was performed to study the mechanical / rheological behavior of semi-solid Al-Cu alloys. Various deformation techniques, namely, isothermal semi-solid compression, extrusion and indentation were used. The time-resolved dynamic 3D images were analyzed with the help of novel image quantification techniques including digital volume correlation and image-based simulations of fluid flow. The quantified dynamics at a microstructural scale was then linked with macroscopic mechanical properties. The qualitative and quantitative analyses revealed a range of important semi-solid micromechanical mechanisms including the occurrence and effects of dilatancy, associated liquid flow through the equiaxed microstructure, intra-dendritic deformation, and strain localization during semi-solid deformation, not only shedding new insights into the mechanisms of deformation-induced solidification defect formation (solute segregation, porosity and hot tearing) of semi-solid alloys at both a macroscopic and microscopic level, but also providing benchmark cases for semi-solid deformation models and theories. The experimental methodology, techniques and analysis procedures developed in this thesis are generic in nature and can be applied to a wide range of research fields.

The continuous casting process is a widely used technique in modern steel plants. However, it is a complicated process that is not well understood. The objective of this research is to model the porosity and macrosegregation due to shrinkage related effects and solid deformation in the continuous casting of steel. Solid phase movements due to bulging and variable roll gap are modeled with a simple algebraic equation based on assumed slab surface deflection. A simplified single domain fluid flow model is derived to predict the pressure field. When liquid pressure drops to zero, porosity starts to form. The distribution of porosity is calculated using the porosity equation which is based on the mass conservation. A macrosegregation model based on the species conservation is derived. With the relative velocity calculated from the pressure results and the solid velocity, macrosegregation is obtained. Since the solid phase velocity is not zero and mixture density is not assumed to be constant, porosity and macrosegregation due to both solid deformation and shrinkage effects are incorporated. In order to validate the model, the pressure field of a three-dimensional pure metal solidification system is simulated. The results show the feasibility of the proposed model to predict the fluid flow. The porosity and macrosegregation prediction for different casting conditions are performed. The results confirm the necessity of including solid phase deformation in the prediction of porosity and centerline macrosegregation. The results also reveal the relations between different operating conditions (such as degree of bulging, soft reduction, and casting speed) and the porosity/macrosegregation defects in the final product.