On food and cooking the science and lore of the kitchen ( PDFDrive ) 1490
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surface,andtheironnevergetsthe
opportunitytorust.
Thischemicalstabilityisboughtataprice.
Stainlesssteelismoreexpensivethancast
ironandcarbonsteel,andit’sanevenpoorer
heatconductor.Theadditionoflargenumbers
offoreignatomsapparentlyinterfereswith
electronmovementbycausingstructuraland
electricalirregularitiesinthemetal.The
transferofheatinastainlesspancanbe
evenedoutbycoatingtheundersideofthepan
withcopper,orbyinsertingacopperor
aluminumplateinthepanbottom,orby
makingthepanoutoftwoormorelayers,
withagoodconductorjustunderthesurface.
Ofcoursetheserefinementsaddfurthertothe
costoftheutensil.Still,thesehybridsarethe
closestthingwehavetotheidealchemically
inertbutthermallyresponsivepan.
Tin
Tinwasprobablyfirstusedincombination
withcoppertomakethemechanicallytougher
alloycalledbronze.Todaytinisgenerally
foundonlyasanontoxic,unreactiveliningin
copperutensils.Thislimitedroleistheresult
oftwoinconvenientproperties:alowmelting
point,450ºF/230ºC,thatcanbereachedin
somecookingprocedures,andasoftnessthat
makesthemetalverysusceptibletowear.The
tinalloycalledpewter,whichusedtocontain
someleadandnowismadewith7%antimony
and2%copper,isnotmuchusedtoday.
