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88 SMT Magazine • August 2016 and emphasized the importance of miniatur- izing circuitry with high density interconnect technology. The roadmap also addresses spin-in opportunities and legislation threats posed by REACH and RoHS. The REACH regulations and their impact on space hardware were also covered by Asen- sio Zapata of Airbus-Toulouse, their surface treatment and M&P expert. Of particular im- portance to the space industries will be the ex- clusion of hexavalent chromium whose sunset date is expected to be September 2017. This is of significant concern due to such chemicals being used extensively for the corrosion protection of spacecraft electronics and structures. The work- horse, Alodine 1200, employed throughout spacecraft hardware for surface corrosion pro- tection, or as a primer for paints, also has a low contact resistance which is ideal for the ground- ing of spacecraft electronics constructed from aluminium based alloys. Zapata's laboratory research covered many coatings and indicated that alternative Cr+6 -free conversion coatings, such as SurTec R 650, may have suitable proper- ties for passivating aluminium along with low contact resistance—this coating has a faintly visible blue coloration. Engineers Ángel Bustos and Iñaki Hernanz, from SENER, Spain described an extensive veri- fication program where a space-approved ad- hesive staking compound was used to provide more robustness to 3D-Plus EEPROMs solder- mounted onto PCBs (Figure 4). Without special component-lead bending design such adhesives can over-stress solder joints due to their high thermal expansion coefficients (during both assembly/curing and subjection to thermal cy- cling during verification tests). Of particular importance is the application point of the glue – by trial and error this location was optimized in order to satisfy both the vibration and the thermal cycling test environments stipulated by ECSS-Q-ST-70-38 (the European space standard: "High-reliability soldering for surface-mount and mixed Technology"). The development of a thermally conductive carbon fiber reinforced polymer (CFRP) manu- factured electronic box for space applications was described by Luis Pina on behalf of teams from Portugal and Germany (led by INEGI, Uni- versity of Porto), a study financed by ESA. The CFRP test structure represented a mass saving of 23% when compared to a similarly shaped aluminum housing. The electrical conductivity (Figure 5) and thermal conduction of the CFRP material was enhanced by adding carbon nano- tubes to a special epoxy resin system developed by Huntsman for "low outgassing under vacu- Figure 4: Populated PCB that included 3D-Plus EEPROMs for SMT Verification testing. (SENER) Figure 5: Electrical resistivity measurements being performed on a prototype CFRP electronic housing: Resistance between metallic base-plate and bonding studs < 0.1Ω. Resistance between housing surface and bonding stud (shown above) < 1 Ω. Maximum resistance between two arbitrary points on this housing <10 Ω. (INEGI). 7TH ELECTRONIC MATERIALS AND PROCESSES FOR SPACE WORKSHOP