Many of the components we work with are encapsulated in either highly filled epoxies or in foams of varying density. Encapsulation is performed for a variety of reasons, including high voltage standoff, shock and vibration isolation, stress relief, environmental isolation, etc.
We not only perform encapsulation, but we conduct research into the component-encapsulation adhesive bond, fracture of the adhesive bond, the stress developed during cure, cure kinetics of the encapsulant material, and the effect of inclusions on the bulk stress field. We have worked to develop more environmentally friendly substitutes for the traditional epoxies and foams. We can help you choose an encapsulant material, develop a cure schedule that minimizes stress on the components, test the encapsulant, and actually perform the encapsulation.
- Encapsulation:Foams, elastomers, and rigid resins (epoxies, silicones and polyurethanes) are used to protect electrical devices from shock and vibration. These encapsulants provide rugged protection and help to ensure a long service life for the component. We have the expertise to design molds, fixture parts and perform the encapsulation.
- Large Scale Foaming: We have experience foaming oversized objects; often in complicated geometries.
Materials Selection: We will work with you to select materials that have the desired properties, a processing routine compatible with the components being encapsulation, a chemistry that is compatible with the components, and minimal environmental hazards.
- Cleaning/Surface Preparation: We use a variety of surface preparation techniques such as: solvent cleaning (both traditional and alternative), plasma cleaning, sandblasting, chemical etching and priming.
Encapsulant Research: We perform research into the stresses developed as a result of curing, the mechanisms behind interface debonding, and flow visualization of the filler materials. We have worked to develop simple tools for characterizing the flow parameters of a highly filled polymer.
- Abrasive blasters
- Microprocessor controlled ovens
- Autoclaves up to 4 ft. diameter x 8 ft. long
- High shear planetary mixer
- UV Curing
- Walk-in oven
- Dry wall (walk-in hood)
- Vacuum casting equipment
- Plasma cleaner
- Terpene based cleaning system
- Class 100 clean bench
- Gradient cure apparatus
- Environmental temperature cycling with optional humidity control
- As a result of flow visualization experiments, modified the encapsulation process for the neutron generator - dramatically increasing the yield and cutting the process fill time.
- Validated encapsulation cure stress models for the neutron generator that were used to decrease the cure time by a factor of two.
- Development of simple tools for characterizing the flow properties of flip-chip underfill encapsulation material.
- Development of a desktop model for the flow of flip-chip packaging underfill material through a solder bump field. The model predicts the flow pattern and formation of voids.
- Small lot production of multiple components (Manganin Foil Gauges, Neutron Generators, Current Stacks, and Thermal Batteries) under weapons reserve quality guidelines.
- Sandia President's Quality Award (Gold) for small lot production of active ceramics.
John A. Emerson