Cov khoom siv hlau uas muaj cov yam ntxwv ntawm cov xim hlau feem ntau yog tsim los ntawm ob lossis ntau dua hlau los yog hlau-raws li ntxiv ntawm lwm yam tsis yog hlau los ntawm cov txheej txheem alloying (melting, mechanical alloying, sintering, vapor deposition, etc.) hu ua alloys. Tab sis cov hlau yuav tsuas muaj ib qho hlau, xws li hlau. (Steel yog cov ntsiab lus dav dav rau ferroalloys nrog cov ntsiab lus carbon ntawm 0.02% thiab 2.00% los ntawm huab hwm coj)
Ntawm no peb yuav tsum nco ntsoov tias cov hlau tsis yog cov ntsiab lus sib xyaw ua ke, lossis txawm tias cov khoom siv ntshiab, xws li ib-theem intermetallic compound alloy. Cov ntsiab lus alloying ntxiv tuaj yeem tsim cov kev daws teeb meem, cov khoom sib txuas, thiab tsim cov tshuaj tiv thaiv endothermic lossis exothermic, yog li hloov cov hlau. Qhov xwm ntawm matrix.
Kev tsim cov alloys feem ntau txhim kho cov khoom ntawm cov ntsiab lus. Piv txwv li, lub zog ntawm cov hlau yog ntau dua li ntawm nws cov ntsiab lus tseem ceeb, hlau. Cov khoom ntawm lub cev ntawm cov hlau, xws li qhov ntom ntom, reactivity, Young' s modulus, hluav taws xob conductivity thiab thermal conductivity, tej zaum yuav zoo ib yam li cov ntsiab lus ntawm cov hlau, tab sis lub zog tensile thiab shear lub zog ntawm cov hlau. feem ntau muaj feem xyuam rau cov khoom ntawm cov khoom siv. nrog qhov sib txawv loj. Qhov no yog vim qhov kev npaj ntawm atoms nyob rau hauv lub alloy thiab lub caij yog txawv heev.
Ib qho me me ntawm qee lub caij yuav muaj kev cuam tshuam zoo rau cov khoom ntawm cov hlau. Piv txwv li, impurities hauv ferromagnetic alloys tuaj yeem hloov cov khoom ntawm cov hlau.
Tsis zoo li cov hlau ntshiab, feem ntau cov alloys tsis muaj qhov chaw ruaj khov. Thaum qhov kub thiab txias yog nyob rau hauv lub melting kub ntau, qhov sib tov yog nyob rau hauv lub xeev ntawm coexistence ntawm cov khoom thiab kua. Yog li ntawd, nws tuaj yeem hais tau tias qhov chaw melting ntawm cov hlau yog qis dua li ntawm cov khoom siv hlau. Saib eutectic sib tov. Ntawm cov hlau alloys, tooj dag yog ib qho alloy ntawm tooj liab thiab zinc; bronze yog ib qho alloy ntawm tin thiab tooj liab, siv rau cov pej thuam, ornaments thiab pawg ntseeg tswb. Qee cov txiaj ntsig siv alloys (xws li nickel alloys).