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The ability to learn is a gift The capacity to learn is a skill The willingness to learn is a choice - Rebec of Ginaz. tensile. yield. tensile/yield. Re: question from last class - Mech prop data for annealed plain carbon steels. Also from last class: Densities of some materials:
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The ability to learn is a gift The capacity to learn is a skill The willingness to learn is a choice - Rebec of Ginaz
tensile yield tensile/yield Re: question from last class - Mech prop data for annealed plain carbon steels
Also from last class: Densities of some materials: Al alloys 2.63-2.82 gm/cm3 steels 6.92-9.13 Ti alloys 4.43-4.70 Mg alloys 1.77-1.78 Cu alloys 7.47-8.94 glasses 2.4-2.7 HDPE 0.96 PMMA 1.22 epoxies 1.25
Lotus versatile vehicle architecture system (VVA) Almost completely "aluminum" - high pressure die-castings, stampings, and extrusions Advanced Materials & Processes, July 2005, p 29 Al???
OK…..which "aluminum" is it? 1050 1145 2014 2024 2219 2618 3003 3004 3105 4032 4043 5005 5052 5083 5154 5182 5262 5652 6010 6061 6262 6463 7005 7050 7072 7075 7175 7178 7475 7229 . . .
Does NOT contain 0.61% carbon OK…..which "aluminum" is it? 1050 1145 2014 2024 2219 2618 3003 3004 3105 4032 4043 5005 5052 5083 5154 5182 5262 5652 6010 6061 6262 6463 7005 7050 7072 7075 7175 7178 7475 7229 Alloy designation NOT same as steels In fact, no carbon at all in ordinary Al alloys
1050 1145 2014 2024 2219 2618 3003 3004 3105 4032 4043 5005 5052 5083 5154 5182 5262 5652 6010 6061 6262 6463 7005 7050 7072 7075 7175 7178 7475 7229
Number Major alloy addition 1xxx - 2xxx Cu 3xxx Mn 4xxx Si 5xxx Mg 6xxx Mg & Si 7xxx Zn 8xxx other Here’s the scoop -
Yield strength Tensile strength Low-strength 30 ksi 60 ksi steel Pure aluminum 5 ksi 13 ksi Al alloy 2024-T4 47 ksi 68 ksi So, does alloying affect the properties? Al alloy containing 4.4% Cu (say 2024) can be heat treated to strength level much higher than that of pure Al
So, does alloying affect the properties? Al alloy containing 4.4% Cu (say 2024) can be heat treated to strength level much higher than that of pure Al Yield strength Tensile strength Low-strength 30 ksi 60 ksi steel Pure aluminum 5 ksi 13 ksi Al alloy 2024-T4 47 ksi 68 ksi What’s this??
T4 designates a heat treatment (Al alloys only) "solution heat-treated, quenched, and naturally aged to a substantially stable condition"
T4 designates a heat treatment (Al alloys only) "solution heat-treated, quenched, and naturally aged to a substantially stable condition" How do we know this works?…….& why does it make the material stronger?
A portion of the Al-Cu "phase diagram" How do we know it works? We consult a road map for the material system
A new concept - the solid solution A single Cu-Zn alloy is formed Then, where are the Zn atoms??