GENNEXT MATERIALS & TECHNOLOGIES LLC — National Aeronautics and Space Administration SBIR Phase I: Z10

Description

The fusion welds of dissimilar refractory metals suffer from many limitations including shrinkage cavities, solidification cracking, embrittlement due to impurities, inferior strength and ductility, increased fabrication cost etc. GenNext Materials and Technologies, LLC proposes to develop dissimilar refractory metal friction welds for fabricating hollow cathodes free from these limitations.nbsp;nbsp;To achieve the improved weld performance, life time, manufacturing reliability and cost savings, the proposed joining technique, viz., friction welding, has inherent advantages over the state-of-the-art joining methods, including:The hollow cathode structural dissimilar refractory materials can be joined readily and reliablyThe absence of melting and solidification eliminates cavities, cracking and embrittlement in the friction welds nbsp;The mechanical alloying of the dissimilar metals leads to solid solution formation eliminating brittle phases and improvement in weld reliabilityThe friction welding process enables lowering the hollow cathode manufacturing cost due to superior performance and prolonged life of welds, short weld cycles and simple joint preparations