GLTRS--Glenn
TITLE AND SUBTITLE:
Iridium-Coated Rhenium Radiation-Cooled Rockets

AUTHOR(S):
Brian D. Reed, James A. Biaglow, and Steven J. Schneider

REPORT DATE:
July 1997

FUNDING NUMBERS:
WU-632-1B-1B

PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES):
National Aeronautics and Space Administration
Lewis Research Center
Cleveland, Ohio 44135-3191

PERFORMING ORGANIZATION REPORT NUMBER:
E-10736

SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES):
National Aeronautics and Space Administration
Washington, DC 20546-0001

REPORT TYPE AND DATES COVERED:
Technical Memorandum

SPONSORING/MONITORING AGENCY REPORT NUMBER:
NASA TM-107453

SUPPLEMENTARY NOTES:
Prepared for the International Symposium on Rhenium and Rhenium Alloys sponsored by the Minerals, Metals, and Materials Society, Orlando, Florida, February 9-13, 1997. Responsible person, Brian D. Reed, organization code 5430, (216) 977-7489.

ABSTRACT:
Radiation-cooled rockets are used for a range of low-thrust propulsion functions, including apogee insertion, attitude control, and repositioning of satellites, reaction control of launch vehicles, and primary propulsion for planetary spacecraft. The key to high performance and long lifetimes for radiation-cooled rockets is the chamber temperature capability. The material system that is currently used for radiation-cooled rockets, a niobium alloy (C103) with a fused silica coating, has a maximum operating temperature of 1370 °C. Temperature limitations of C103 rockets force the use of fuel film cooling, which degrades rocket performance and, in some cases, imposes a plume contamination issue from unburned fuel. A material system composed of a rhenium (Re) substrate and an iridium (Ir) coating has demonstrated operation at high temperatures (2200 °C) and for long lifetimes (hours). The added thermal margin afforded by iridium-coated rhenium (Ir/Re) allows reduction or elimination of fuel film cooling. This, in turn, leads to higher performance and cleaner spacecraft environments. There are ongoing government- and industry-sponsored efforts to develop flight Ir/Re engines, with the primary focus on 440-N, apogee insertion engines. Complementing these Ir/Re engine development efforts is a program to address specific concerns and fundamental characterization of the Ir/Re material system, including (1) development of Ir/Re rocket fabrication methods, (2) establishment of critical Re mechanical property data, (3) development of reliable joining methods, and (4) characterization of Ir/Re life-limiting mechanisms.

SUBJECT TERMS:
Iridium; Rhenium, Radiation-cooled rockets; Rhenium joining; Iridium/rhenium
fabrication; rhenium properties; Satellite propulsion

NUMBER OF PAGES:
16

PDF AVAILABLE FROM URL:
1997/TM-107453.pdf
(155,776 KB)
This page contains an Adobe® Acrobat® Reader PDF file. The PDF documents have been created to show thumbnails of each page. If the thumbnails do not display properly, download the file to the hard drive and view through Acrobat® Reader. You can download Acrobat® Reader for free. click

NASA NASA GLTRS--Glenn

A service of the NASA Glenn Research Center Logistics and Technical Information Division

Suggestions or questions about this site can be directed to:

NASA official: Technical Publications Manager, Sue.E.Butts@nasa.gov

Web curator: Caroline.A.Rist@grc.nasa.gov

Privacy Policy and Important Notices