Editing Inconel (section)

==Properties==
When heated, Inconel forms a thick and stable [[Passivation (chemistry)|passivating]] oxide layer protecting the surface from further attack. Inconel retains strength over a wide temperature range, attractive for high-temperature applications where [[aluminium]] and [[steel]] would succumb to [[Creep (deformation)|creep]] as a result of thermally induced crystal vacancies (see [[Arrhenius equation]]). Inconel's high temperature strength is developed by [[solid solution strengthening]] or [[precipitation strengthening]], depending on the alloy. In [[age hardening|age-hardening]] or precipitation-strengthening varieties, small amounts of [[niobium]] combine with [[nickel]] to form the [[intermetallic]] compound Ni<sub>3</sub>Nb or [[Superalloy#Families of superalloys|gamma double prime]] (γ″). Gamma prime forms small cubic crystals that inhibit [[Slip (materials science)|slip]] and creep effectively at elevated temperatures. The formation of gamma-prime crystals increases over time, especially after three hours of a heat exposure of  {{Convert|850|C|F}}, and continues to grow after 72 hours of exposure.<ref>{{cite web|url=http://www.doitpoms.ac.uk/miclib/full_record.php?id=716|title=DoITPoMS - Full Record|website=www.doitpoms.ac.uk}}</ref>