skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: FY2014 LX-21 Aging and Compatibility


Abstract not provided.

 [1];  [1];  [1];  [1];  [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Technical Report
Country of Publication:
United States

Citation Formats

Gash, Alexander E., Fowzia, Zaka, Montgomery, Jennifer, Turner, Heidi, Glascoe, Elizabeth, and Harley, Stephen. FY2014 LX-21 Aging and Compatibility. United States: N. p., 2015. Web. doi:10.2172/1184156.
Gash, Alexander E., Fowzia, Zaka, Montgomery, Jennifer, Turner, Heidi, Glascoe, Elizabeth, & Harley, Stephen. FY2014 LX-21 Aging and Compatibility. United States. doi:10.2172/1184156.
Gash, Alexander E., Fowzia, Zaka, Montgomery, Jennifer, Turner, Heidi, Glascoe, Elizabeth, and Harley, Stephen. 2015. "FY2014 LX-21 Aging and Compatibility". United States. doi:10.2172/1184156.
title = {FY2014 LX-21 Aging and Compatibility},
author = {Gash, Alexander E. and Fowzia, Zaka and Montgomery, Jennifer and Turner, Heidi and Glascoe, Elizabeth and Harley, Stephen},
abstractNote = {Abstract not provided.},
doi = {10.2172/1184156},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2015,
month = 3

Technical Report:

Save / Share:
  • In order to design a thermoelectric (TE) module suitable for long-term elevated temperature use, the Department 8651 has conducted parametric experiments to study material compatibility and thermal aging of TE materials. In addition, a comprehensive material characterization has been preformed to examine thermal stability of P- and N-based alloys and their interaction with interconnect diffusion barrier(s) and solder. At present, we have completed the 7-days aging experiments for 36 tiles, from ambient to 250 C. The thermal behavior of P- and N-based alloys and their thermal interaction with both Ni and Co diffusion barriers and Au-Sn solder were examined. Themore » preliminary results show the microstructure, texture, alloy composition, and hardness of P-(Bi,Sb){sub 2}Te{sub 3} and N-Bi{sub 2}(Te,Se){sub 3} alloys are thermally stable up to 7 days annealing at 250 C. However, metallurgical reactions between the Ni-phosphor barriers and P-type base alloy were evident at temperatures {ge} 175 C. At 250 C, the depth (or distance) of the metallurgical reaction and/or Ni diffusion into P-(Bi,Sb){sub 2}Te{sub 3} is approximately 10-15 {micro}m. This thermal instability makes the Ni-phosphor barrier unsuitable for use at temperatures {ge} 175 C. The Co barrier appeared to be thermally stable and compatible with P(Bi,Sb){sub 2}Te{sub 3} at all annealing temperatures, with the exception of a minor Co diffusion into Au-Sn solder at {ge} 175 C. The effects of Co diffusion on long-term system reliability and/or the thermal stability of the Co barrier are yet to be determined. Te evaporation and its subsequent reaction with Au-Sn solder and Ni and Co barriers on the ends of the tiles at temperatures {ge} 175 C were evident. The Te loss and its effect on the long-term required stoichiometry of P-(Bi, Sb){sub 2}Te{sub 3} are yet to be understood. The aging experiments of 90 days and 180 days are ongoing and scheduled to be completed in 30 days and 150 days, respectively. Material characterization activities are continuing for the remaining tiles.« less
  • A materials study of high reliability electronics cleaning is presented here. In Phase 1, mixed type substrates underwent a condensed contaminants application to view a worst- case scenario for unremoved flux with cleaning agent residue for parts in a silicone oil filled environment. In Phase 2, fluxes applied to copper coupons and to printed wiring boards underwent gentle cleaning then accelerated aging in air at 65% humidity and 30 O C. Both sets were aged for 4 weeks. Contaminants were no-clean (ORL0), water soluble (ORH1 liquid and ORH0 paste), and rosin (RMA; ROL0) fluxes. Defluxing agents were water, solvents, andmore » engineered aqueous defluxers. In the first phase, coupons had flux applied and heated, then were placed in vials of oil with a small amount of cleaning agent and additional coupons. In the second phase, pairs of copper coupons and PWB were hand soldered by application of each flux, using tin-lead solder in a strip across the coupon or a set of test components on the PWB. One of each pair was cleaned in each cleaning agent, the first with a typical clean, and the second with a brief clean. Ionic contamination residue was measured before accelerated aging. After aging, substrates were removed and a visual record of coupon damage made, from which a subjective rank was applied for comparison between the various flux and defluxer combinations; more corrosion equated to higher rank. The ORH1 water soluble flux resulted in the highest ranking in both phases, the RMA flux the least. For the first phase, in which flux and defluxer remained on coupons, the aqueous defluxers led to worse corrosion. The vapor phase cleaning agents resulted in the highest ranking in the second phase, in which there was no physical cleaning. Further study of cleaning and rinsing parameters will be required.« less
  • The addition of a hydrogen transfer system (Carle Instruments) to a Hewlett-Packard 5880A gas chromatograph has enabled us to quantitate hydrogen in addition to other gases produced during compatibility testing of explosives. This report describes our particular modification and gives results which describe its capabilities. 9 refs., 4 figs., 3 tabs.
  • An aging and compatibility study has been conducted with the MC1442 thermal battery igniter to determine the effects of a hydrogen atmosphere on the energetic materials. Igniters were aged up to one (1) year at 70/sup 0/C in a 50/50 hydrogen/helium and also a pure helium atmosphere to simulate a 25-year aging environment at the normal thermal battery storage temperature. Functional testing with the igniter, including an all-fire Langley sensitivity format, function time and photographic flame profile measured no deviations from baseline samples. Analytical testing for changes in the energetic materials during aging measured less than 5% reaction of themore » nitrocellulose and no detectable reaction of the LMNR/KC10/sub 3/ ignition mixture. The hydrogen atmosphere reacted with the nitrocellulose at a rate greater than two times that observed for the helium-aged igniters. Since igniter performance was not affected by aging in hydrogen or helium, it was concluded that the MC1442 would function reliably in a thermal battery environment containing hydrogen.« less