AN ABSURDLY QUICK LOOK AT METAL ALLOYS

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AN ABSURDLY QUICK LOOK AT METAL ALLOYS
There are specifications for literally thousands
of alloys. What is available? How do we choose
an alloy for a given application?
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STEEL COMPANIES ORGANIZE ALLOYS LIKE THIS
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MATERIAL SPECIFICATIONS ABOUND
ASTM A or B plus digits (e.g., A 36, A 240,
A 516, B 443, B 811) plus (sometimes) other
identifiers ASME SA or SB plus
digits AISI Types 4 (or occasionally 5) digits
for low alloy steels, 3 digits (plus possibly a
letter) for stainless steels Aluminum
Association alloys 4 digits, first indicates
primary alloying element American Welding
Society (e.g., A5.14 ERNiCrMo-3) Unified
Numbering System (UNS) letter plus five
digits Proprietary specifications
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SOME GENERALIZATIONS ARE POSSIBLENOTABLE
PROPERTIES OF SOME ALLOY CLASSES
Low alloy steels Cast irons Stainless
steels Nickel-base alloys Titanium
alloys Aluminum alloys Magnesium
alloys Zirconium alloys Copper alloys
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MANY ALUMINUM ALLOYS CAN BE PRECIPITATION HARDENED
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PRECIPITATES IMPEDE DISLOCATION MOTION