In physics the truth is rarely perfectly clear, and that is certainly the case with human affairs. Hence, what is not surrounded by uncertainty cannot be the truth

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In physics the truth is rarely perfectly clear,
and that is certainly the case with human
affairs. Hence, what is not surrounded by
uncertainty cannot be the truth Richard
Feynman
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OK, then, what about "ceramic" tools?
Most from Al2O3 - pressed to near-net shape
sintered at 1600-1700 C - ground on diamond
wheels
At high temps, high hardness, wear resistance Can
use for mat'ls w/ up to RC66
Very brittle Cost 2X that of carbide tools
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Types White - C is all in CM Grey - C as
graphite flakes Ductile (nodular) - C as
graphite nodules
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White - C is all in CM very brittle,
wear resistant, not machinable,
limited use
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Carburizing - pack gas - add C from CO gas
Nitriding - add N from NH3
Case must be Q T, except for nitrided
Carbonitriding - add C N from CO NH3
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Ford uses SAE 1050 steel with manganese content
modified from 0.80 to 1.10 in rear axle
shafts. Normally 0.60-0.90 Mn YS 49 ksi, TS
90 ksi, EL 15 (hot-rolled) YS 80 ksi, TS
120 ksi (QT) depends on
heat treat conditions
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Assignment Review today's classnotes a. cast
irons b. case hardening c. Jominy test d.
Jominy curves e. quench severities Read in
text pp. 339-345, 219-220, 531-532 see
photos on pp. 91, 446