CERAMIC AND GLASS JOINING Sandia National Laboratories has developed an unequaled set of techniques for engineering ceramic-metal and glass-metal joints as a by-product of its national defense mission. Our approach combines the work of materials scientists, mechanical designers, and process engineers to insure that selected component designs are manufacturable, and that joining technology is effectively integrated early in the product design process. When joining is ignored until after the design is fixed, it is often a significant constraint rather than an enabling part of the process. Applications High temperature joining of engine components for the aerospace industry. Solid oxide, fuel cell joining. Sealing of housings for medical implants. Microelectronic packaging. Sensors for extreme environments such as oil logging. Lightweight electrical connectors for space applications. Heat exchangers. Manifolds and supports for ceramic filters. Membranes and filters for gas and liquid separations. Potential Benefits Sandia's proprietary finite element modeling (FEM) codes and fast super computers can efficiently test component designs without the need to build prototypes. Sandia's capability for developing novel ceramics, glasses and joining products and processes insures compatibility with candidate alloys, thus freeing component engineers from the constraints of current joining technology, and enabling the development of new products and devices with improved performance. Demonstrated Achievements High strength pyrotechnic actuators, similar to those used in automotive air bags, were developed to withstand 150,000 psi gas pressure bursts. The technology was subsequently patented and licensed to over 15 private companies for commercial development. Long-life lithium battery seals were developed with a lifetime of 25 years and are now the industry standard for lithium batteries. Sandia engineers developed a hermetic Si on quartz accelerometer using an electric field assisted bonding process at temperatures below 1000 C. A process for making hermetic seals to Al has been developed that reduces the weight of large electrical connectors and exhibits greater strength and reliability than alternatives. Patented hermetic Ti connectors were developed based on a class of borate sealing glasses that matched CTEs to titanium and that bond directly without adverse reactivity. Work under a CRADA with a major US company developed techniques for making Si3N4 joints that will survive 1000 C. These are the strongest ceramic joints at 1000 C ever reported. References Several patents issued and dozens of papers presented. Proprietary software for FEM calculations. A short course on joining has been developed by senior scientists from Sandia National Laboratories that is presented at national technical meetings and is available for presentation on-site at companies. Sandia is interested in partnering with industry to further develop reliability and failure analysis of glass and ceramic components. Companies interested in partnering with Sandia should bewilling to sponsor a collaborative project via a Cooperative Research and Development Agreement (CRADA) with Sandia. For further information please respond by mail or fax to Sheila Pounds by July 2, 1999 at Sandia National Laboratories, MS-1380, P. O. Box 5800, Albuquerque, New Mexico 87185-1380. Fax: (505) 843-4163. Please indicate the date and title of this CBD notice. E-MAIL: Sheila L. Pounds, slpound@sandia.gov. Posted 06/18/99 (W-SN344640).

Loren Data Corp. http://www.ld.com (SYN# 0467 19990622\SP-0001.MSC)