Most Commonly Used Materials

1. Most Commonly Used Materials The following 25 materials are the most commonly used materials in the design of mechanical products; in themselves they represent the broad range of other materials. Steel and Cast Iron • 1020 (plain carbon steel, hot-rolled or cold-drawn) • 1040 (plain carbon steel, hot-rolled or cold-drawn) • 4140 (heat-treated alloy steel, chromium-molybdenum) • 4340 (heat-treated alloy steel, nickel-chromium-molybdenum) • S30400 (stainless steel) • S316 (stainless steel) • O1 (tool steel) • ASTM20-60 (gray cast iron) Product Design and Manufacturing, SJSU

2. Aluminum and Copper Alloys • 2024 (aluminum, O, T3, T4 or T6) • 3003 (aluminum, H12 or H16) • 6061 (aluminum, T6) • 7075 (aluminum, T6) • C268 (copper) Other metals • Titanium 6-4 • AZ63A (magnesium) Most Commonly Used Materials Product Design and Manufacturing, SJSU

3. Ceramics • Alumina • Graphite Composite materials • Douglas fir • Fiberglass • Graphite/epoxy Most Commonly Used Materials Plastics • ABS • Polycarbonate • Nylon 6/6 • Polypropylene • Polystyrene Product Design and Manufacturing, SJSU

4. Application of Most Commonly Used Materials Component Material Product Design and Manufacturing, SJSU

5. Application of Most Commonly Used Materials Component Material Product Design and Manufacturing, SJSU

6. Material Component Application of Most Commonly Used Materials Product Design and Manufacturing, SJSU

7. Properties of Most Commonly Used Materials Ultimate Strength in tension Product Design and Manufacturing, SJSU

8. Properties of Most Commonly used Materials Yield strength Product Design and Manufacturing, SJSU

9. Properties of Most Commonly used Materials Fatigue endurance limit (strength under cyclic loading) Product Design and Manufacturing, SJSU

10. Properties of Most Commonly used Materials Density Product Design and Manufacturing, SJSU

11. Cost of Most Commonly used Materials Product Design and Manufacturing, SJSU

12. Example – Materials for table legs Luigi Tavolino, furniture designer, conceives of a lightweight table of daring simplicity: a flat sheet of toughened glass supported on slender, unbraced, cylindrical legs. The legs must be solid and as light as possible (to make the table easier to move). They must support the table top and whatever is placed upon it without buckling.What materials could one recommend. Product Design and Manufacturing, SJSU

13. Objective function Example – Materials for table legs The Model The leg is a slender column of density ρ and modulus E. The load P and its length l are determined by design (fixed). The radius r of the leg is a variable. We wish to minimize the mass m of the leg. Product Design and Manufacturing, SJSU

14. = Material properties The weight is minimized by selecting the subset of materials with the greatest value of the material index. Example – Materials for table legs The constraint is that the legs must support a design load without buckling. Euler’s buckling equation where I = πr4/4 Solving for the free variable , r, and substituting it into the equation for m gives, Product Design and Manufacturing, SJSU

15. The thinnest leg is that made of the material with the largest value of the material index. Two material indices, To minimize the weight, both have to be maximize. Example – Materials for table legs Solving the Euler’s formula for r, gives an equation for the thinnest leg which will not buckle: Material properties Product Design and Manufacturing, SJSU

16. Procedure for deriving material indices Product Design and Manufacturing, SJSU

17. Modulus of Elasticity (E) vs. Density (ρ) Charts Constant guidelines Product Design and Manufacturing, SJSU

18. Modulus of Elasticity (E) vs. Density (ρ) Charts Product Design and Manufacturing, SJSU

19. Modulus of Elasticity (E) vs. Density (ρ) Charts Product Design and Manufacturing, SJSU

20. Product Design and Manufacturing, SJSU

21. Summary of materials for table legs Product Design and Manufacturing, SJSU