Tom qab cov ntsiab lus alloying tau ntxiv rau cov hlau, lawv muaj nyob hauv cov hlau hauv peb daim ntawv tseem ceeb. Ntawd yog: ua ib qho kev daws teeb meem nrog hlau; tsim carbide nrog carbon; thiab tsim intermetallic compounds nyob rau hauv high alloy steel.
1. Dissolved nyob rau hauv hlau
Yuav luag tag nrho cov ntsiab lus alloying (tshwj tsis yog Pb) tuaj yeem yaj hauv cov hlau los ua alloy ferrite lossis alloy austenite. Raws li lawv cov teebmeem ntawm -Fe lossis -Fe, cov ntsiab lus alloying tuaj yeem muab faib ua ob pawg: nthuav dav austenite theem cheeb tsam thiab shrinking austenite theem cheeb tsam.
Cov ntsiab lus uas nthuav cov theem theem - tseem hu ua austenite stabilizing cov ntsiab lus, feem ntau yog Mn, Ni, Co, C, N, Cu, thiab lwm yam. Lawv ua rau A3 point (-Fe -Fe hloov pauv point) poob thiab A4 point ( -Fe kev hloov pauv taw tes) nce, yog li nthuav dav qhov muaj nyob ntawm -theem. Ntawm lawv, Ni, Mn, thiab lwm yam, thaum ntxiv rau qee qhov nyiaj, tuaj yeem nthuav cov theem theem mus rau hauv qab chav tsev kub, ua rau theem cheeb tsam ploj mus, uas yog hu ua lub caij uas nthuav dav cov theem theem. Qee lwm cov ntsiab lus (xws li C, N, Cu, thiab lwm yam), txawm hais tias lawv nthuav dav thaj tsam ntawm theem, tsis tuaj yeem nthuav dav rau hauv chav tsev kub, yog li lawv raug hu ua cov ntsiab lus uas ib feem nthuav dav cheeb tsam.
Cov ntsiab lus uas txo cov theem hauv cheeb tsam - tseem hu ua ferrite stabilizing cov ntsiab lus, feem ntau muaj xws li Cr, Mo, W, Ti, Al, Si, B, Nb, Zr, thiab lwm yam. Lawv nce A3 taw tes thiab txo qhov A4 point (tshwj tsis yog chromium, thaum cov ntsiab lus chromium tsawg dua 7%, A3 taw tes txo qis; Raws li lawv cov kev ua haujlwm sib txawv, lawv tuaj yeem muab faib ua cov ntsiab lus uas kaw tag nrho cov theem cheeb tsam (xws li Cr, Mo, W, V, Ti, Al, Si, thiab lwm yam) thiab cov ntsiab lus uas txo cov theem cheeb tsam (xws li B. , Nb, Zr, etc.).
2. Carbide-forming alloying ntsiab yuav muab faib ua ob pawg: carbide-forming ntsiab thiab non-carbide-forming ntsiab raws li lawv affinity nrog carbon nyob rau hauv steel.
Cov ntsiab lus uas tsis yog-carbide tsim muaj xws li: Ni, Co, Cu, Si, Al, N, B, thiab lwm yam. Lawv yog cov yaj hauv ferrite thiab austenite. Cov ntsiab lus carbide feem ntau muaj xws li: Mn, Cr, W, V, Nb, Zr, Ti, thiab lwm yam. Ib txhia ntawm lawv yog yaj nyob rau hauv matrix theem nyob rau hauv steel, thiab ib co daim ntawv alloy cementite. Thaum cov ntsiab lus siab, cov hlau alloy tshiab tuaj yeem tsim tau.
