1. Landing Gear Alloy and Composite Analysis By David Cobler

2. Problem The landing gear for the Lunar Lander Satcube must take up the minimum amount of space required and be as light as possible.

3. Solution Analyze various Alloys and Composites for a material that is very strong and light weight. – Aircraft grade Aluminum – Aluminum-Lithium Alloy 8090 – Beryllium-Aluminum Alloy 363 – Titanium Ti-6-2-4-2 – Carbon-Epoxy

4. Comparison Criteria Material Properties – Focusing mainly on Yield Strength and Density Availability and Cost

5. Aircraft Aluminum Somewhat light weight Low strength Many suppliers Cheap Yield Strength Modulus Of ElongationDensity 11.0 ksi10600 ksi0.100 lb/in³ %Elongation @ Break Poisson's Ratio Shear Strength 20.00%0.3318000 psi

6. Aluminum-Lithium Alloy 8090 Lighter than Aircraft Aluminum Much stronger than Aircraft Aluminum Not Readily Available Very Expensive Yield Strength Modulus Of ElongationDensity 53.7 ksi11200 ksi0.0918 lb/in³ %Elongation @ Break Poisson's Ratio Shear Strength 7.00%0.30539200 psi

7. Beryllium-Aluminum Alloy 363 Lightest Aluminum Alloy Not as strong as Al-Li Not Readily Available Expensive Permanent and or fatal respiratory hazards when machining Yield Strength Modulus Of ElongationDensity 30.990 ksi29300 ksi0.0780 lb/in³ %Elongation @ Break Poisson's Ratio Shear Strength 3.00%0.235900 psi

8. Titanium Ti-6-2-4-2 Not very light weight Very strong Specialty Suppliers Somewhat Pricy Yield Strength Modulus Of ElongationDensity 144.0 ksi17,400 ksi0.164 lb/in³ %Elongation @ Break Poisson's Ratio Shear Strength 3.00%0.32100,000 psi

9. Carbon-Epoxy Sheet Extremely light weight Very strong Specialty suppliers Relatively Cheap Yield Strength Modulus Of ElongationDensity 87.0 ksi10200 ksi0.0578 lb/in³ %Elongation @ Break Poisson's Ratio Shear Strength 0.80%None Found13100 psi

10. Overall Comparison Yield Strength 11.0 ksi 144000 psi 87000 psi 53700 psi 30990 psi Density 0.100 lb/in³ 0.164 lb/in³ 0.0578 lb/in³ 0.0918 lb/in³ 0.0780 lb/in³ Yield Strength/Density 110ksi/(lb/in³) 878ksi/(lb/in³) 1505ksi/(lb/in³) 584ksi/(lb/in³) 397ksi/(lb/in³) Aircraft Aluminum Titanium Ti-6-2-4-2 Carbon Fiber Epoxy Aluminum Lithium alloy 8090 Beryllium-aluminum The Beryllium and Lithium Alloys are to expensive, unavailable, or warrant health risks that do not make them appropriate. Aircraft Aluminum is the Cheapest material at about 15$ per ft^2 Carbon-Epoxy was found around 65$ per ft^2 Titanium was found to be much higher and ranging in prices.

11. Questions?