AME 20217 Lab II B 2 Uniaxial Tension

AME 20217 - Lab II B 2 – Uniaxial Tension AME 20217 - Rumbach 1

B 1 - Longitudinal vs. Hoop Stress Hoop strain is always greater than longitudinal strain! AME 20217 - Rumbach 2

Boundary effects or “edge effects” Rigid end cap were not considered in theoretical derivation. AME 20217 - Rumbach 3

Senior Design Fabrication technique is critical! “Solderless” bread board AME 20217 - Rumbach Soldered bread board 4

Solid Mechanics – Hooke’s Law For a spring AME 20217 - Rumbach For any material 5

Beyond Hooke’s Law “Plastic” region “Linear-elastic” AME 20217 - Rumbach 6

Hot rolled vs. cold rolled steel samples Hot rolled: https: //www. youtube. com/watch? v=6 xn. Kmt_gs. Ls&authuser=0 Cold drawn: https: //www. youtube. com/watch? v=Xz. CQyw. Fwies&authuser=0 For Sale: https: //www. alibaba. com/product-detail/Top-Quality-Machinery-New-Design-Hot_60540176243. html AME 20217 - Rumbach 7

Stress-strain Curves Cold-rolled Steel AME 20217 - Rumbach Hot-rolled Steel 8

B 2 – Uniaxial Tensile Tests You will use an ATS load frame to measure a stress-strain curve of steel. BRING A FLASH DRIVE! AME 20217 - Rumbach 9

Linear Variable Displacement Transducer (LVDT) Inserting a steel rod into a solenoid changes its inductance. μ is “magnetic permeability” http: //www. ni. com/ AME 20217 - Rumbach http: //www. digikey. com/ 10

Extensometer Clips onto sample, measures change in length ΔL. AME 20217 - Rumbach 11

Load Cell Outputs a voltage proportional to force. http: //www. interfaceforce. com/index. php? mod=product&show=5 AME 20217 - Rumbach https: //en. wikipedia. org/wiki/Load_cell 12