Question: If you had to choose a metal to make a crankshaft which
would you use.
Moldex uses 4340. Carol Smith's "Engineer to Win" says that
it is an excellent metal. However, they say that there is a 4340
modified metal that is superior in some respects but possibly not
in others. This Modified 4340 has a trace of Vanadium which is
supposed to give it more grain streingth.
Does it matter who makes/processes metal? i.e. which
foundry?
The book indicates that 4340 should not be hardened to
Rockwell C of ?43-46- it becomes very brittle.
After the Crank is made and testing of hardness is done
can the actual crank be tested or should Coupons treated
simultaneously with the Crank be tested instead? Does the
hardness testing injure the metal?
Any metallurgists with advice?
Thanks,
Mordy Dunst
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