Lesson 4: Materials Selection & Strength
Duration of Days: 3.5
Lesson Objective
SWBAT:
Compare the tensile strength and density of common shop metals.
Calculate the total weight of a subsystem based on material choice and volume.
If Aluminum is lighter than Steel, why don't we build the whole chassis out of Aluminum?
How does "Work Hardening" affect the safety of a suspension part over time?
Tensile Strength, Density, Alloy, Fatigue, Work Hardening, Ductility, Brittle.
CT-CTE.TRANS.B.11 (Material properties); CT-CTE.MFG.B.07 (Volume/Weight math).
DOK Level: 2 (Application)
Students analyze the physical properties of materials to choose the best option based on strength-to-weight ratios.
Misconception: "Stronger is always better."
Correction: Excessively strong parts are often excessively heavy, which reduces efficiency.
Support: Use a "Material Sample Kit" for tactile comparison.
Extension: Conduct destructive tests on sample welds.
The Material Pitch: Present a material choice for their part and justify it with data points.