Thermal modeling of an epoxy encapsulation process

Baca, R G; Schutt, J A

Title: Thermal modeling of an epoxy encapsulation process

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Abstract

The encapsulation of components is a widely used process at Sandia National Laboratories for packaging components to withstand structural loads. Epoxy encapsulants are also used for their outstanding dielectric strength characteristics. The production of high voltage assemblies requires the encapsulation of ceramic and electrical components (such as transformers). Separation of the encapsulant from internal contact surfaces or voids within the encapsulant itself in regions near the mold base have caused high voltage breakdown failures during production testing. In order to understand the failure mechanisms, a methodology was developed to predict both the thermal response and gel front progression of the epoxy the encapsulation process. A thermal model constructed with PATRAN Plus (1) and solved with the P/THERMAL (2) analysis system was used to predict the thermal response of the encapsulant. This paper discusses the incorporation of an Arrhenius kinetics model into Q/TRAN (2) to model the complex volumetric heat generation of the epoxy during the encapsulation process. As the epoxy begins to cure, it generates heat and shrinks. The total cure time of the encapsulant (transformation from a viscous liquid to solid) is dependent on both the initial temperature and the entire temperature history. Because the rate of cure ismore »« less

Authors:: Baca, R G; Schutt, J A

Publication Date:: Tue Jan 01 00:00:00 EST 1991

Research Org.:: Sandia National Labs., Albuquerque, NM (United States)

Sponsoring Org.:: USDOE; USDOE, Washington, DC (United States)

OSTI Identifier:: 5327762

Report Number(s):: SAND-90-3048C; CONF-9110196-2
ON: DE91017845

DOE Contract Number:: AC04-76DP00789

Resource Type:: Conference

Resource Relation:: Conference: PATRAN users conference, Newport Beach, CA (United States), 1-3 Oct 1991

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; 42 ENGINEERING; ENCAPSULATION; Q CODES; EPOXIDES; DIELECTRIC PROPERTIES; THERMODYNAMIC PROPERTIES; TRANSFORMERS; COMPUTER PROGRAM DOCUMENTATION; ELECTRICAL INSULATION; FAILURES; GELS; MATHEMATICAL MODELS; COLLOIDS; COMPUTER CODES; DISPERSIONS; ELECTRICAL EQUIPMENT; ELECTRICAL PROPERTIES; EQUIPMENT; ORGANIC COMPOUNDS; ORGANIC OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; 360603* - Materials- Properties; 990200 - Mathematics & Computers; 426000 - Engineering- Components, Electron Devices & Circuits- (1990-)

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                    Baca, R G, and Schutt, J A. Thermal modeling of an epoxy encapsulation process.  United States: N. p., 1991. 
        Web.

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                    Baca, R G, & Schutt, J A. Thermal modeling of an epoxy encapsulation process.  United States.

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                    Baca, R G, and Schutt, J A. 1991.  
        "Thermal modeling of an epoxy encapsulation process".  United States.

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@article{osti_5327762,

  title        = {Thermal modeling of an epoxy encapsulation process},

  author       = {Baca, R G and Schutt, J A},

  abstractNote = {The encapsulation of components is a widely used process at Sandia National Laboratories for packaging components to withstand structural loads. Epoxy encapsulants are also used for their outstanding dielectric strength characteristics. The production of high voltage assemblies requires the encapsulation of ceramic and electrical components (such as transformers). Separation of the encapsulant from internal contact surfaces or voids within the encapsulant itself in regions near the mold base have caused high voltage breakdown failures during production testing. In order to understand the failure mechanisms, a methodology was developed to predict both the thermal response and gel front progression of the epoxy the encapsulation process. A thermal model constructed with PATRAN Plus (1) and solved with the P/THERMAL (2) analysis system was used to predict the thermal response of the encapsulant. This paper discusses the incorporation of an Arrhenius kinetics model into Q/TRAN (2) to model the complex volumetric heat generation of the epoxy during the encapsulation process. As the epoxy begins to cure, it generates heat and shrinks. The total cure time of the encapsulant (transformation from a viscous liquid to solid) is dependent on both the initial temperature and the entire temperature history. Because the rate of cure is temperature dependent, the cure rate accelerates with a temperature increase and, likewise, the cure rate is quenched if the temperature is reduced. The temperature and conversion predictions compared well against experimental data. The thermal simulation results were used to modify the temperature cure process of the encapsulant and improve production yields.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/5327762},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Jan 01 00:00:00 EST 1991},

  month        = {Tue Jan 01 00:00:00 EST 1991}

}

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