Molybdenum Alloys

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Molybdenum Alloys
In contrast to the other bcc refractory metals
molybdenum is a relatively abundant material in
the Earths crust and reasonable quantities of
fine grained material can be prepared by
consumable electrode melting or by powder
metallurgy followed by sintering.
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Molybdenum Alloys
Mo and W form a continuous series of solid
solutions and the resultant solution
strengthening increases the degree of strain
hardening that can be obtained by cold work Ti
and Zr are added to form a fine dispersion of
carbides in order to restrict the
recrystallization of Mo so that strain
hardening can be retained to higher
temperatures Mo-5Re and Mo-41Re alloys have been
developed for improved high-temperature strength
but such alloys are not regarded as cost
effective at the present time as Re is a
relatively scarce and expensive metal
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Microstructure of Mo Alloys
Fine grained structure of Mo prepared by powder
metallurgy and sintering
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Effect of Temperature on UTS of Mo Alloys
As the basis of dispersive strengthening is the
retention of cold work the advantages of
dispersive phase alloying disappear above the
recrystallization temperature of 1000-1300 oC
when pure Mo is just as strong
Key 1 TZM cold worked 2 Pure Mo cold worked 3
TZM recrystallized 4 Pure Mo recrystallized
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