Case Studies

A plastic clip used to retain a patient support failed, resulting in an occupant death. Veryst was asked to determine the cause of failure.

Polymer foams may exhibit extreme strain rate-dependence due to their structure. The low stiffness means testing the materials at high strain rates is particularly difficult. Veryst has developed multiple test methods to test and model these materials.

Obtaining accurate results from finite element analyses of polymers is not easy. Polymers are often highly temperature- and rate-dependent, exhibiting significant stress-relaxation, creep, and recovery. In this forming case study, Veryst examines the steps required to produce an accurate constitutive model of an example polymer, polyether ether ketone (PEEK), and shows the consequences of oversimplification.

All commercial FE packages provide material models for polymers, but Veryst Engineering’s PolyUMod® material library has advanced material models at the leading edge of polymer mechanics. We demonstrate the accuracy of a PolyUMod material model with native material models from Abaqus, ANSYS, and LS-DYNA.

Cold forging often results in the development of high residual stresses that might lead to premature cracking of the cold forged component. Machining, which often follows cold forging, results in the re-distribution of residual stresses. We developed an FE-based strategy capable of predicting the residual stresses in the final machined configuration of cold forged components.

Manufacturing medical diagnostic kits involves drying reagents to be reconstituted later, during use. For this project, Veryst simulated reagent dry-down of a small volume of liquid in a microwell to investigate the effect of process parameters including oven temperature and humidity.

Designing an assembly process using a thermoset adhesive can be challenging without an understanding of the adhesive curing kinetics. Veryst engineers use FTIR spectroscopy to analyze curing and optimize processing steps.

Materials that have been deformed past their yield point and into the plastic strain region often display permanent deformation upon removal of load. How much of this deformation is truly permanent? Veryst has developed a method to measure the residual strain of materials following unloading as a function of time.

Radio frequency tissue ablation is a commonly used and minimally invasive tissue treatment procedure. Accurately modeling this kind of coupled multiphysics problem is often challenging. Veryst developed a COMSOL Multiphysics model accounting for heat transfer, electric field, and fluid flow to study the RF tissue ablation problem where an electrode is targeting a tissue close to a blood vessel.