In-mold assembly can be used to create mesoscale articulating polymeric joints that enable the miniaturization of devices, reduction of production costs, and increase in throughput. One of the major challenges in miniaturizing devices using in-mold assembly is to develop appropriate characterization techniques and modeling approaches for the interaction between polymer melt flow fronts and prem...

Using the phenol-terminated polycarbonate blend as an example, we demonstrate that the hydrodynamic boundary conditions for a flow of an adsorbing polymer melt are extremely sensitive to the structure of the epitaxial layer. Under shear, the adsorbed parts (chain ends) of the polymer melt move along the equipotential lines of the surface potential whereas the adsorbed additives serve as the sur...

We employ a continuous theory of two-phase flow to investigate the influence of grain boundary tension on distribution and migration of melts through a viscous matrix. The ‘disaggregation melt fraction’, the volume fraction of partial melt at which grain boundaries are completely wetted, is crucial in determining the total interfacial force per unit volume. In partially molten aggregates with s...

Rates of ice mass loss at the calving margins of tidewater glaciers (frontal ablation rates) are a key uncertainty in sea level rise projections. Measurements are difficult because mass lost is replaced by ice flow at variable rates, and frontal ablation incorporates sub-aerial calving, and submarine melt and calving. Here we derive frontal ablation rates for three dynamically contrasting glaci...

Polymeric materials often exhibit complex combustion behaviours encompassing several stages and involving solid phase, gas phase and interphase. A wide range of qualitative, semi-quantitative and quantitative testing techniques are currently available, both at the laboratory scale and for commercial purposes, for evaluating the decomposition and combustion behaviours of polymeric materials. The...

An online numerical simulation is presented that is capable of predicting state variables such as flow rate, melt temperature, shear rate, and melt viscosity by using real time data from a nozzle pressure sensor. The simulation solves the non-Newtonian nonisothermal polymer flow into multicavity tools while executing rapidly enough for real time process control. Numerical accuracy and stability...

Chemical differentiation of rocky planets occurs by melt segregation away from the region of melting. The mechanics of this process, however, are complex and incompletely understood. In partially molten rocks undergoing shear deformation, melt pockets between grains align coherently in the stress field; it has been hypothesized that this anisotropy in microstructure creates an anisotropy in the...

The effects of filler content and its surface treatment with silane coupling agent on the melt shear viscosity of glass bead-filled polypropylene (PP) composites have been investigated using a capillary rheometer at a wide shear rate scope of 150 to 7200 s and temperature range of 160 to 200 C. The melt flow obeys power law, but the slopes of the flow curves have transitions at the shear rate o...

[1] Global observations of mid-ocean ridge (MOR) bathymetry demonstrate an asymmetry in axial depth across ridge offsets that is correlated with the direction of ridge migration. Motivated by these observations, we have developed two-dimensional numerical models of asthenospheric flow and melting beneath a migrating MOR. The modification of the flow pattern produced by ridge migration leads to ...