Kev kho cua sov ntawm aluminium guardrail castings suav nrog kev tswj cov cua sov kom sov rau qee lub sijhawm thiab txias ntawm qee tus nqi los hloov cov qauv ntawm cov hlau. Lub hom phiaj kawg yog txhawm rau txhim kho cov khoom siv hluav taws xob ntawm cov hlau, txhim khu kev tiv thaiv corrosion, txhim kho kev ua haujlwm, thiab ua tiav qhov kev ruaj ntseg.
Nrog steel nrog cov ntsiab lus siab carbon, siab hardness yog tam sim ntawd tau tom qab quenching, thaum plasticity tsawg heev. Txawm li cas los xij, qhov no tsis yog qhov teeb meem rau aluminium alloys. Tom qab quenching, lub zog thiab hardness ntawm aluminium alloy tsis tam sim ntawd nce, thiab lub plasticity tsis tsuas yog txo, tab sis kuj nce. Tab sis rau qhov no quenched alloy, tom qab ib lub sij hawm ntawm lub sij hawm, nws lub zog thiab hardness yuav ho nce, thaum nws plasticity yuav pom zoo txo. Qhov tshwm sim uas lub zog thiab hardness ntawm aluminium alloy ho nce nrog lub sij hawm tom qab quenching yog hu ua kev laus. Kev laus tuaj yeem tshwm sim nyob rau hauv chav tsev kub, hu ua natural aging, los yog nyob rau ntawm qhov kub thiab txias siab tshaj li chav tsev kub, hu ua kev laus laus.
Lub hnub nyoog hardening ntawm aluminium alloys yog ib qho txheej txheem tseem ceeb, uas tsis tsuas yog nyob ntawm qhov muaj pes tsawg leeg thiab cov txheej txheem kev laus ntawm cov hlau, tab sis kuj nyob ntawm qhov tsis xws luag los ntawm qhov shrinkage ntawm cov hlau thaum lub sij hawm tsim khoom, tshwj xeeb tshaj yog cov naj npawb thiab dispersion ntawm voids. dislocations. Nws yog dav ntseeg hais tias lub hnub nyoog hardening yog tshwm sim ntawm solute atom segregation tsim ib tug hardened cheeb tsam.
Thaum quenching cua sov, voids yog tsim nyob rau hauv lub alloy. Vim tias qhov txias txias sai, cov voids no tsis tuaj yeem raug tshem tawm hauv lub sijhawm thiab "nrawm" rau hauv cov khoom siv lead ua. Cov voids nyob rau hauv supersaturated solid solutions feem ntau yog txuam nrog solute atoms. Vim lub xeev tsis ruaj khov ntawm supersaturated solid tov, nws yuav tsum tau hloov mus rau lub xeev equilibrium. Lub hav zoov ntawm voids accelerates qhov diffusion tus nqi ntawm cov atoms solute, yog li accelerating lub segregation ntawm solute atoms.