Powder Metal Bus Structure for a Nanosatellite. David Bellieveau & Catherine Price Mechanical Engineering Department

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1 Powder Metal Bus Structure for a Nanosatellite David Bellieveau & Catherine Price Mechanical Engineering Department Advisor: Professor Apelian Co-Advisor: Professor Looft

2 PANSAT Mission Statement The purpose of the student-led Powder metallurgy And Navigation SATellite (PANSAT) mission is to provide an opportunity for WPI students to learn about satellite design and to establish a framework for future satellite research at WPI

3 Project Goal Prove that Powder Metal (PM) components can be used to create the bus structure of a nanosatellite, while satisfying NASA's safety requirements.

4 Project Objectives Design a Nanosatellite Bus Structure Create a Die for PM Walls of Bus Structure Perform Tests on PM sample bars Tensile Testing Scanning Electron Microscope (SEM) Compare PM sample bar results to their wrought counterparts for structural integrity

5 Bus Structure Design 45cm x 41cm x 1cm 19.5cm x 16cm x 1cm The key component of the structure s design is modularity. One wall is comprised of two parts fastened together. This design came about because producing more PM components lowers production costs and the structure is now stackable.

6 Material Selection Material Options: Aluminum: Alcoa AB201* AMP 2712* Titanium: Ti 6V4Al Powders donated by: *Metal Powder Products Dynamet

7 Material Conditions Pressed Density Condition Treatment (g/cc) Ti (99%) All - CHIP Dynamet N/A Alcoa _ - HIP Bodycote 960ºF x 14,750 psi for 2hrs Ampal _ - HIP Bodycote 960ºF x 14,750 psi for 2hrs

8 PM Sample Bars Comparisson of All Five Materials Stress (ksi) Strain (%) Ti64 Alcoa Al 201 Ampal Al 2712 HIPed Alcoa HIPed Ampal UTS Ti64 It is clear in the above graph the ductility and strength shown by Titanium (blue line).

9 PM Sample Bars Comparisson of Aluminum Materials Stress (ksi) Strain (%) Alcoa Al 201 Ampal Al 2712 HIPed Alcoa HIPed Ampal UTS HIPed Ampal This graph compares just the Aluminum materials for a more detailed look. HIPed Ampal is much more ductile than the others.

10 PM Sample Bars Comparisson of Aluminum Materials Stress (ksi) Strain (%) Alcoa Al 201 Ampal Al 2712 HIPed Alcoa UTS HIPed Alcoa UTS Alcoa UTS Ampal This graph shows the thee Aluminums with the closest properties. Ampal 2712 has a higher UTS than the rest.

11 PM Versus Wrought Wrought Al6061-T6 Powder Metal HIPed Ampal Al6711 Powder Metal HIPed Alcoa Al201 Powder Metal Ampal Al6711 Powder Metal Alcoa Al201 Wrought Ti-6Al-4V Powder Metal Ti-6Al-4V Density (g/cc) Ultimate Tensile Strength (MPa) Yield Strength (MPa) Elongation at Fracture (%) Modulus of Elasticity (GPa) The table above highlights important comparable data gained through testing and researching the listed materials. A few points of interest to acknowledge in this particular table are Ti64 is approximately 3-4 times stronger than all of the Aluminum materials. Also, the PM Titanium is even stronger than it s wrought counterpart.

12 PM Fracture Surface This image show the grain boundaries of the Aluminum powder. This signifies the powders are sintered. Alcoa 201 at 100X.

13 PM Fracture Surface This image shows the dimples formed by the powder particles. Dimples indicate ductility /ductile fracture. Titanium 64 at 250X.

14 PM Fracture Surface This image shows a single pellet fused with the rest of the component. HIP Ampal 2712 at 1000X.

15 Recommendations PANSAT will be continued through January by two WPI students. All of our data and progress will be transformed to these students, with the following conclusion and recommendations: Conclusion: Pushing the use of Titanium 6V4Al for the BUS Structure Benefits: Provides 3-4 times stronger than tested Aluminum specimens. Recommendation: Size down thickness of walls by _ Benefits: Provides same mass budget as Aluminum with twice the strength.

16 Acknowledgements Special Thanks to: Susan Abkowitz, Dynamet Technology, Inc. Chaman Lall, Metal Powder Products Jane L. LaGoy, Bodycote HIP, Inc. Bill Weir, WPI Machine Shop Steve Derosier, WPI Machine Shop Qingyue Pan, WPI Materials Lab Sumanth Shankar, WPI SEM Lab