The U. S. Patent and Trademark Office
(USPTO) has granted Lockheed Martin a patent for a new and innovative,
near-zero erosion, net-molded ceramic rocket nozzle throat for solid rocket
motors. The new ceramic material promises to improve solid rocket motor
affordability and performance compared to the current state-of-the-art 4D
carbon-carbon material.

In 1997, Lockheed Martin Space & Strategic Missiles, Sunnyvale, Calif.
initiated an advanced materials technology development project to assess the
feasibility of using ceramic materials in solid rocket motor nozzle throats
as part of an ongoing company-funded Independent Research and Development
(IRAD) program. The patent (Patent Number 6,510,694 B2) was issued on Jan.
28, 2003.

Propulsion design engineers with the Fleet Ballistic Missiles (FBM) program
teamed with materials scientists from the company’s Advanced Technology
Center in Palo Alto, Calif. to develop and static test a ceramic as a
low-erosion rocket nozzle throat material. FBM engineers are developing this
high-temperature advanced ceramic material for potential use in future
strategic missile-sized solid rocket motors, however, the new nozzle throat
material also holds promise for other applications including tactical
missiles and thrusters.

“This is a significant technology breakthrough,” said Joe Zegarski, solid
rocket motor advanced project lead at Lockheed Martin. “Other organizations
all over the world have been trying to develop a zero-erosion throat since
the early 1960’s. Our invention will help Lockheed Martin provide its
customers with more cost effective missile systems in the future.” In a
series of scale-up tests using throats specimens up to 2″ in diameter and
300 lb rocket motors containing either Class 1.3 or Class 1.1 propellants,
the Lockheed Martin ceramic demonstrated to have less than 0.1 mils/second
erosion rate and outperformed (i.e., had less erosion than) 4D Carbon-Carbon
by a factor of 20. The ceramic throat inserts were fabricated using a
net-molding technique, that is expected to provide a greater than 50%
reduction in fabrication cost and procurement lead-time compared to those of
Carbon-Carbon.

Additional tests of the cost saving ceramic throat technology are planned
for the future. The ATC recently fabricated the largest ceramic-lined nozzle
throat insert to date, a 5.2-inch throat insert that will be tested with an
800-pound, Class 1.1 solid rocket motor.

In January 2003, Technology Review–published by the Massachusetts Institute
of Technology (MIT)– for the third consecutive year ranked Lockheed Martin
first in the aerospace industry for the technological strength and
innovation of its patents. Last year, USPTO issued 199 patents to Lockheed
Martin from a total of 500 patent applications submitted by Lockheed Martin
engineers and scientists.

Space & Strategic Missiles is a part of Lockheed Martin Space Systems
Company, headquartered in Denver, Colo., one of the major operating units of
Lockheed Martin Corporation. Space Systems designs, develops, tests,
manufactures and operates a variety of advanced technology systems for
military, civil and commercial customers. Chief products include space
launch and ground systems, remote sensing and communications satellites for
commercial and government customers, advanced space observatories and
interplanetary spacecraft, fleet ballistic missiles and missile defense
systems.

Headquartered in Bethesda, Maryland, Lockheed Martin employs about 125,000
people worldwide and is a global enterprise principally engaged in the
research, design, development, manufacture and integration of advanced
technology systems, products, and services. The Corporation reported 2002
sales of $26.6 billion.