Question

16. Use the Modulus-Relative cost chart of to find, from among the materials that appear on it (a) the cheapest material with a modulus greater than 1 GPa (b) the cheapest metal (c) the cheapest polymer (d) whether magnesium alloys are more or less expensive than aluminium alloys (e) whether PEEK (a high performance engineering polymer) is more or less expensive than PTFE Technical ceramics Modulus-Relative cost/vol WC Stainless SiC SgN B,C 1000 W alloys Silicon 20 steels Carbon steels AIN Zinc alloys Cast irons Al alloys Metals Non-technical ceramics 100 Tilalloys Soda glass Storie Brick Concrete Silica glass Lead alloys CFRP Mg alloys Composites grain GFRP 10 Epoxies Natural materials PMMA Acetal PS PP PEEK PC Wood -Polymers -Polyurethanes I grain Rigid polymer foams Foams ABS lonomers PE: PTFE Leather Flexible polymer loams 0.1 EVA Polyurethane Silicone elastomers 0.01 Elastomers MFA, 07 0.01 0.1 1 10 100 Relative cost per unit volume, Cy R 17. Which material properties do you need to minimise/maximise to avoid thermal shock? Young's modulus, E (GPa)

Answer 1

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