R·I·T Kate Gleason College of Engineering Design of a Tensile Load Frame for a Scanning Electron Microscope Senior Design Project Project Manager - Robert Rinefierd Faculty Mentor - Dr. Elizabeth Debartolo

R·I·T – Senior Design Kate Gleason College of Engineering Team Members Project Manager – Robert Rinefierd Lead Engineer – Evan Kastner Mechanical Engineers –Nicholas Currier, Evan Kastner, Robert Rinefierd, Blaine Stuart Industrial Engineer –Kennedy Mogwai Computer Engineer –Evan Brunner

R·I·T – Senior Design Kate Gleason College of Engineering Agenda Project Overview Objectives and Specifications Final Design Manufacturing and Assembly Production Report Recommendations

R·I·T – Senior Design Kate Gleason College of Engineering Project Overview Design and construct a load frame to apply tensile loads to specimens inside the Scanning Electron Microscope (SEM) in the CIMS Materials Science Lab The load frame should be lightweight, modular, and easy to carry between buildings Developed for Mechanical Engineering Department faculty and students performing metallographic research Funded by the Mechanical Engineering department

R·I·T – Senior Design Kate Gleason College of Engineering Objectives and Specifications Performance –200 lbs Compression, 2000 lbs Tension –Position and Load Control –Live Displays Implementation –Cylindrical Threaded Specimen –Remove Part of Position Frame Evaluation –Pass Fatigue and Stress Calculations Safety –Vacuum –Electrical Grounding

R·I·T – Senior Design Kate Gleason College of Engineering Design Constraints Spatial constraints Vacuum compatibility CIMS Materials Lab owns the SEM; Mechanical Engineering department will own the load frame –Load frame to mount to existing position fixture –Limited to existing ports for vacuum feedthrough Budget - $7,500

R·I·T – Senior Design Kate Gleason College of Engineering Existing SEM Load Frames Lehigh University concept –Tension, bending, compression –Spur gears and worm gears US Patent –Temperature controlled Southwest Research Institute (Dr. Davidson) –Fatigue testing capability Custom designs for individual applications Provided general ideas

R·I·T – Senior Design Kate Gleason College of Engineering Final Design Six basic Modules Motor and Gear Box Drivetrain Gripping Base and frame Control system Vacuum interface Motor and gearboxSpecimen Lead screwFixed end and base Grip and collar Free end GearsLoad cell

R·I·T – Senior Design Kate Gleason College of Engineering Motor and Gearbox Selection Motor Specifications: –Vacuum Rating – torr –Maximum torque of 2 in·lb, driven at ~1 in·lb Gearbox Specifications: –Vacuum Rating – torr –Reduction Ratio – 700:1 –Maximum torque output of 1040 in·lb Cost is high, but parts are necessary

R·I·T – Senior Design Kate Gleason College of Engineering Drivetrain - Gears Consists of two 2.5” diameter spur gears and a 1” diameter pinion gear. Gearing reduction of 2.5 Case hardened 8620 steel Spur gears transmit torque to the power screws though keys.

R·I·T – Senior Design Kate Gleason College of Engineering Drivetrain - Power Screws ACME G threaded rods with end machining - self locking capability Gray iron ACME nuts inserted in free end Keyway Gear shaft Bearing shaft ACME thread

R·I·T – Senior Design Kate Gleason College of Engineering Drivetrain – Bearings and Nuts Fixed end – bearing bores for shafts Bearings and washers to reduce friction and add stability Free end – ACME nuts instead of taps

R·I·T – Senior Design Kate Gleason College of Engineering Grip Design 3/8 – 24 threaded grip Load cell acts as opposite grip Easy to change samples Standard ASTM threaded samples Test Area –Gage length of 1 inch –Diameter of ¼ inch CollarGripLoad Cell

R·I·T – Senior Design Kate Gleason College of Engineering Base and Frame Purpose –Interface between load frame and SEM –Mounting surface for stage –Hold SEM position resolution device Function –Matched bolt holes –Designed to withstand 100 lb external force (leaning) while it sits on a table.

R·I·T Kate Gleason College of Engineering Control System- Physical Layout

R·I·T – Senior Design Kate Gleason College of Engineering Controls Control through LabView End user definable USB Minilab 1008 Stock or freeware libraries Hard emergency stop

R·I·T – Senior Design Kate Gleason College of Engineering Vacuum Interface Available port 2 ¾ “ Flange Vacuum chamber Pro/E Model

R·I·T – Senior Design Kate Gleason College of Engineering Stress Analysis Selected hand calculations for major components

R·I·T – Senior Design Kate Gleason College of Engineering Stress Analysis Verified preliminary calculations done for major parts Shear stress, Von Mises stress, and displacement in gears, free end, and ACME shafts Load conditions were maximum possible

R·I·T – Senior Design Kate Gleason College of Engineering Design for Manufacture and Assembly Assembly sequence DFA Index – 6.23% Minimum Number of Parts - 15 Theoretical number of parts -61 Estimated cost - $

R·I·T – Senior Design Kate Gleason College of Engineering Manufacturing and Assembly Manufacturing Plan –Machine sequence –Tolerances –Quality checks –Total hours –Pro/E drawings –Cutting speed and feed rates –Machine tools

R·I·T – Senior Design Kate Gleason College of Engineering Cost Analysis

R·I·T – Senior Design Kate Gleason College of Engineering Production Report Early March: –Completed of all aspects of mechanical design –Submitted purchase order for components Mid-March: –Completion of detailed design including FEA analysis –Design for assembly analysis April: –Fabrication of steel components –Development of control system with LabView –Submit order for all additional standard components May: –Assembly and troubleshooting Early June: –Motor and gearbox expected to arrive for assembly –Electromechanical integration and system troubleshooting

R·I·T – Senior Design Kate Gleason College of Engineering Recommendations Weight of load frame may be an issue Alignment – threads are general fit rather than precision fit Position resolution - encoder Optimize control system after motor arrives

R·I·T – Senior Design Kate Gleason College of Engineering Acknowledgements Dr. DeBartolo – Faculty Mentor Dave Hathaway and Steve Kosciol Dave Fister, Mike Haselkorn, Newton Green – NCR³ Charlie Clark and Frank Rheaume – Gleason Works Ron Foster – Empire Magnetics

R·I·T – Senior Design Kate Gleason College of Engineering Questions and Discussion