Field repair and replacement part fabrication of military components using ultrasonic consolidation cold metal deposition
conference contributionposted on 15.04.2014, 13:58 by Lee-Ann Schwope, Ross Friel, Kenneth E. Johnson, Russell Harris
Timely repair and replacement of military components without degrading material properties offers tremendous opportunities for cost and schedule savings on a number of military platforms. Effective field-based additive manufacturing repair approaches have proven difficult to develop, as conventional additive metal deposition technologies typically include a molten phase transformation and controlled inert deposition environments. The molten stage of laser and electron beam based additive processes unfortunately results in large dimensional and microstructural changes to the component being repaired or re-fabricated. As a result, high residual stresses and unpredictable ductility profiles in the repair area, or the re-fabricated part, make the final product unsafe for redeployment. Specifically, the heat affected zone associated with traditional deposition-based repair methods can produce a low strength, non-homogenous region at the joint; these changes in the materials properties of the repaired parts are detrimental to the fatigue life, and are a major concern where cyclic loading is experienced. The use of solid state high power Ultrasonic Consolidation (UC) technologies avoids the liquid-solid transition complexity and creates a predictable “cold” bond. This method then allows for strong, homogenous structures to be manufactured and repaired in the field and opens the door for the use of high strength repair material that may reduce the frequency of future failure itself. In addition, UC further offers the opportunity to provide enhanced functionality and ruggedness to a component either during repair or from original manufacture by allowing the embedding of passive and functional elements into the new fabricated component or feature.
- Mechanical, Electrical and Manufacturing Engineering