Development and Testing of Thin Film Shape Memory Effect Optical Membranes

Development of self-deploying, large scale SME membranes, suitable for use in the near term as light collectors and radiators, and in the far term as optical mirrors, requires signficant advances in the materails science of thin film SME materials. Scaleable processing to large (>4m diameter) membranes cannot easily be done for TiNi, however the Shape Memory Alloy AuCd can be processed due to the low reactivity of its constituents. AuCd remains relatively unexplored as a bulk alloy due to cost and as a thin film due to novelty, consequently the material science requires investigation to mature the technology rapidly. In this program, SCT and partners UCLA and Northrop Grumman Space Technologies proposes to accelerate development of AuCd in the polyimide membranes Upilex and CP1. Two different routes will be addressed, on is the development of AuCd from multi-layers using electrodeposition and another using a proprietary thermal spray facility, under development at SCT. After characterization at UCLA, NGST will subject the materials to high radiation environments and measure vapor pressures to start space qualification of the material. Process development of large membranes on the order of 1m will then occur.Large scale development of a deployable mirror will be attempted at the end of the program to demonstrate scaleability.