Master Bond EP21TCHT-1, a two component, thixotropic paste developed for sealing and bonding applications, has been employed in a variety of applications involving a range of substrates and service requirements and conditions.
The use of Master Bond EP21TCHT-1 has been referenced in a number of published research articles from institutes, such as NASA, Princeton University, and University of Florida. This system is a heat resistant epoxy that is serviceable over the temperature range of 4 K to +400 °F, and its properties remain unaffected under cryogenic conditions.
EP21TCHT-1 is a room temperature curing compound that is electrically insulative and thermally conductive. Passing NASA low outgassing testing, this system can be effectively used in vacuum environments.
The following table summarizes the many ways the Master Bond EP21TCHT-1 has been used in research laboratories and commercial applications:
|Magnet bonding and potting 1
||4 K to 478 K
|Sister-block bonding for a telescope 2
||Low outgassing, low CTE, high strength, and ability to be used at cryogenic temperatures.
|Mounting gratings for a telescope 3
||Silicon; titanium alloy; invar
||Operational temperature of 200 K
|Laser packaging assembly 4
||Glass; Si wafers with gold metallization
||4 K to 400 °F service temperature range
|Wire bonding in micro sensor packaging 5
||Gold; TO-39 header
|Mirror coating 6
||NASA low outgassing; used in environments of 10-9 torr
|Teflon wire coated with epoxy; used to secure the wire tie downs to the structure 7
||NASA low outgassing
|Sealing magnetic field coils 8
||Wrapped fiberglass braid
||Epoxy is intended to eliminate vacuum leaks
|Ionizer coating 9
||Ceramic; radioactive silver foil
|Bonding heat dissipation plate to housing wall of laser emitter module 10
||Electrically insulative, thermally conductive
|Solar cell package bonding and sealing 11
||Solar cell; aluminum
|Sealing a probe 12
||NASA low outgassing
|Bonding metal mounting blocks to lenses 13
||Fused silica; metal; zinc selenide; calcium fluoride; sapphire
||Provided really good bond strength, and broke the substrates in some bond strength tests
|Spectrograph camera assembly: Injected between spider and bushing 14
||Optical Lens, ICs, ultem, metals
||Flow; gap filling; precise alignment;
|Bonding heat sink components 15
||NASA low outgassing
|Sister block bonding for space based gravitational wave detectors 16
||Dimensional stability, bond strength
*1 - Teflon needs to be chemically etched for epoxies to adhere to it.
EP21TCHT-1 Application Highlight
The University of Florida carried out a study titled, “Stability Of Materials For Use In Space-Based Interferometric Missions.2” This paper discussed the application of hydroxide bonding for the assembly of instrumentation for space-based missions. For the Laser Interferometer Space Antenna (LISA) mission, a prototype telescope support structure was constructed.
Once the telescope was fabricated, it was identified that a hydroxide bonded strut was tilted. The strut can be dislodged by applying a small amount of force after exposure to -70 °C. The researchers tried to apply sister-block bonding in order to provide extra strength to the multiple struts in the structure, using an epoxy adhesive in combination with hydroxide bonding to adhere SiC to SiC for strut bonding.
After exploring various epoxy compounds, the researchers selected Master Bond EP21TCHT-1 for the sister-block bonding application. This thixotropic paste provided a combination of advantageous properties, including:
- High strength
- Cryogenic serviceability
- Low outgassing
- Low CTE
- Fast room temperature cure
Here, Master Bond EP21TCHT-1 was cured at room temperature for two days, and applied without the need for any surface preparation. Shear strength tests revealed noticeable improvement in results over hydroxide bonding, and confirmed the suitability of applying the Master Bond EP21TCHT-1 thixotropic paste for sister-block bonding.2
1 Wood, Gary J., Andrew Buffalino, Ezekiel Holliday, Barry Penswick, David Gedeon. Free-Piston Stirling Power Conversion Unit For Fission Surface Power, Phase I Final Report. Prepared under Contract NNC08CA65C for National Aeronautics and Space Administration. July 2010. August 25, 2016. http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100031133.pdf
2 Preston, Alix. Stability Of Materials For Use In Space-Based Interferometric Missions. N.P. August 2010. August 2016. http://ufdcimages.uflib.ufl.edu/UF/E0/04/14/95/00001/preston_a.pdf
3 Van Amerongen, Aaldert, Hélène Krol, Catherine Grèzes-Besset, R.W.M. Hoogeveen, Ianjit Bhatti, Dan Lobb, Bram Hardenbol,R.W.M. Hoogeveen. State Of The Art In Silicon Immersed Gratings For Space. ResearchGate. May 19, 2015. July 5, 2016. https://www.researchgate.net/publication/268294938_State_of_the_art_in_silicon_immersed_gratings_for_space
4 Mercado , Emmanuel . Low-Temperature Characterization Of A 1.55-µm Multiple-Quantum-Well Laser Down To 10 K. N.P. May 2013. July 2016. https://repository.unm.edu/bitstream/handle/1928/23201/REVISED%20FINAL.pdf?sequence=1
5 Shu, Huihua. Applications Of Poly (3-Hexylthiophene) Thin Film As A Hydrazine-Sensitive Chemiresistor. N.P. Dec 15, 2006. July 2016. https://etd.auburn.edu/bitstream/handle/10415/570/SHU_HUIHUA_8.pdf?sequence=1
6 Gaunt, Robert, Scott Roberts, Andre Anthony. 2003. “Mechanism For Transmitting Movement In Up To Six Degrees-Of-Freedom.” U.S. Patent 6,543,740 B2, filed September 4, 2001 and issued April 8, 2003. July 2016
7 Owens, Jeremy J. Captain, USAF. Final Assembly, Testing And Processing Of The Rigidizable Inflatable Get-Away-Special Experiment (Rigex) For Spaceflight Qualification. Department Of The Air Force, Air University, Air Force Institute Of Technology, Wright-Patterson Air Force Base, Ohio. Approved For Public Release; Distribution Unlimited. September 2007. July 2016. http://www.dtic.mil/dtic/tr/fulltext/u2/a522020.pdf
8 Hsu, Scott C. Experimental Study of Ion Heating and Acceleration During Magnetic Reconnection. N.P. June 2000. July 2016. http://www.osti.gov/scitech/servlets/purl/750977
9 Denson, Stephen Charles. Improving the Sensitivity and Resolution of Miniature Ion Mobility Spectrometers with a Capacitive Trans Impedance Amplifier. The University of Arizona. 2005. July 5, 2016. http://hdl.handle.net/10150/195646.
10 Liu, Daming, Edmund L. Wolak, Serge Cutillas, 2014. “High Reliability Laser Emitter Modules.” U.S. Patent 8,644,357 B2, filed January 11, 2011 and issued February 4, 2014. http://www.google.ci/patents/US8644357.
11 Zhang, Hongxi, Weiping Lin, Michiharu Yamamoto, 2015. “Packaged luminescent solar concentrator panel for providing high efficiency low cost solar harvesting” U.S. Patent 20150194555 A1, filed Dec 30, 2014 and issued July 9, 2015. http://www.google.ch/patents/US6543740
12 Carter, Troy Alan. Experimental studies of fluctuations in a reconnecting current sheet. Princeton University. November 2001.
13 Echols, Chris. KIRMOS Test Report 06.00 Adhesive Qualification Tests. UCLA. December 4, 2003.
14 Tuttle, Sarah E., Richard D. Allen, Taylor S. Chonis, Mark E. Cornell, Darren L. DePoy, Gary J. Hill, Hanshin Lee, Jennifer L. Marshall, Travis Prochaska, Marc D. Rafal, Richard D. Savage, Brian L. Vattiata. Initial Results from VIRUS Production Spectrographs. University of Texas at Austin, Texas A&M University. http://instrumentation.tamu.edu/files/SPIE/Tuttle_VIRUS_results.pdf
15 Tischler, Tobias. CBM Micro Vertex Detector mechanical integration and cooling. Goethe University Frankfurt. 2011. https://indico.cern.ch/event/144152/contributions/1379153/attachments/133920/190034/MontStOdile_CBMMVDmechanicalintegrationandcooling_TTischler.pdf
16 Sanjuan, J., D. Korytov, G. Mueller, R. Spannagel, C. Braxmaier et al. AIP Review of Scientific Note: Silicon carbide telescope dimensional stability for space-based gravitational wave detectors Instruments. American Institute of Physics. 2012. http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20140009255.pdf
This information has been sourced, reviewed and adapted from materials provided by Master Bond Inc.
For more information on this source, please visit Master Bond Inc.