1. Chess Project Project update presentation 3-20-08

2. Last Week Cast first metal pawns Cast first metal pawns Explored surface smoothing options Explored surface smoothing options Poured investment – failure Poured investment – failure Prepared metallographic samples Prepared metallographic samples Strategized regarding future goals Strategized regarding future goals

3. Wax Density Measurement Density measured using water displacement method Density measured using water displacement method Cast wax: Cast wax: d = 0.78 g/mL d = 0.78 g/mL Relevant when considering detatchment/floating of wax during investment stage Relevant when considering detatchment/floating of wax during investment stage

4. Poor Investment Decision Ceramic did not properly hardened, remained soft and wet for several days Ceramic did not properly hardened, remained soft and wet for several days Likely a problem with the amount of catalyst added (1.2% of powder weight, diluted in water by 3% weight) Likely a problem with the amount of catalyst added (1.2% of powder weight, diluted in water by 3% weight) Salvaged wax pieces, will reinvest over spring break Salvaged wax pieces, will reinvest over spring break

5. Pawn Polishing As-cast (left), sand-blasted (middle), and machine-polished (right) pawns are shown above. Note the difference in coloration. As-cast (left), sand-blasted (middle), and machine-polished (right) pawns are shown above. Note the difference in coloration.

6. Phase Diagram Composition of received material at ~40% zinc Composition of received material at ~40% zinc Some zinc is lost during casting (moves our composition left on the diagram) Some zinc is lost during casting (moves our composition left on the diagram)

7. As-Received Material Both beta and alpha phases present in considerable amounts Both beta and alpha phases present in considerable amounts Few voids in the material Few voids in the material 100x magnification 100x magnification

8. Cast Material Far less alpha phase present in our sample Far less alpha phase present in our sample Many voids visible Many voids visible 100x magnification 100x magnification

9. Phase Diagram

10. New Cast Sample Sample from thicket segment of material taken Sample from thicket segment of material taken More alpha expected to be found in the microstructure More alpha expected to be found in the microstructure Result of thicket cross section and slower cooling rate Result of thicket cross section and slower cooling rate

11. Upcoming Schedule Continue metallographic studies Continue metallographic studies Prepare more wax trees Prepare more wax trees Pour investment, prepare for a “casting week” to get the bulk of our castings completed Pour investment, prepare for a “casting week” to get the bulk of our castings completed Begin surface treatments of already cast pawns Begin surface treatments of already cast pawns