Dynamic Strain Rate Modeling for Multi Ply Boxboard under Rapid Compression
Dynamic strain rate modeling predicts multi-ply boxboard Z-direction compression and interlayer shear collapse during high-speed converting and package drops.
Viscoplastimodels
Rheological Characterization
Nonlinear stress relaxation patterns track the deformation behavior of complex polymer suspensions within high-shear coating environments. These viscoplastimodels simulate the threshold where internal molecular friction forces a transition from liquid flow to solid state deposition. Precise estimation of the yield point prevents uneven layer thickness during the transfer of aqueous binders onto cellulose substrates.
Material Consistency
Analytical solvers apply differential equations to plot the decay of internal tension across extended time intervals. Calculations involving viscoplastimodels determine how structural recovery prevents sagging or pinholing during the initial drying phase of the conversion line. A lower relaxation rate indicates higher resistance to leveling, which complicates the formation of a uniform film thickness.
Manufacturers adjust the solvent ratios or additives to shift the material response closer to the intended mechanical target. Higher initial strain resistance generally requires additional power input for the coating head rollers.
Operational Stability
Industrial production monitors the relationship between shear rate and torque to verify that the rheology remains within the specified operating window for gravure or blade application. Accurate viscoplastimodels provide the quantitative basis for balancing machine speed against the curing speed of the ink or adhesive. Deviations from the projected curve signal a change in the dispersed phase volume that will alter the absorption characteristics of the finished packaging material.
Consistent numerical results allow for tighter tolerances in the final coating weight of the product.