Yuav ua li cas txiav txim siab yog tias cov khoom muaj qhov tsis kam rau cov qoob loo loj hlob

Kev tiv thaiv rau kev loj hlob ntawm cov khoom siv feem ntau yog kev ua haujlwm ntawm nws cov tshuaj muaj pes tsawg leeg, microstructural nta thiab kub stability. Qhov no tuaj yeem ntsuas los ntawm peb qhov loj me hauv qab no:

 

1. Tshuaj muaj pes tsawg leeg tsom xam: Muaj cov ntsiab lus tseem ceeb microalloying

Ti (Titanium), Nb (Niobium), V (Vanium): Cov ntsiab lus no tsim cov carbides ruaj khov (TiC, NbC, VC) uas pin cov ciam teb ntawm qhov kub thiab txias thiab yog li txwv tsis pub cov qoob loo loj hlob.

Al (Aluminium): Deoxidises los muab kev faib tawm ntawm AlN uas cuam tshuam cov coarsening ntawm austenite nplej ntawm cua sov, ib qho tshwj xeeb ntawm "intrinsically fine{0}}grained steel."

W (tungsten), Mo (molybdenum): Daim ntawv siab melting point carbides (piv txwv li WC, Mo2C) thiab txhim kho cov thermal stability ntawm matrix thiab ua rau lub grain ciam tsiv teb tsaws.

Tswv yim tswv yim: Txheeb xyuas daim ntawv pov thawj ntawm cov khoom zoo los yog daim ntawv qhia muaj pes tsawg leeg. Feem ntau ua tau zoo rau kev loj hlob qoob loo yog ua tiav thaum: Ti $\\ge$0.015%, Nb $\\ge$0.02%, V$\\ge$0.1% lossis Al $\\ge$0.02%.

 

2. Microstructure Nta: Thawj grain loj thiab theem ob particles faib

Kev Txiav Txim Siab: Cov khoom siv tiv thaiv kev loj hlob ntawm cov nplej

Kev faib tawm ntawm Precipitated Phase Fine thiab tawg ua ke carbide lossis nitride hais (<1μm) uniformly distributed along grain boundaries.

Initial Grain Size: Fine thawj nplej (GB/T 6394 ntsuam xyuas Ntau dua lossis sib npaug rau 5, nyiam dua 8-10).

Microstructure Homogeneity: Tsis muaj cov khoom siv sib xyaw lossis cov nplej tsis sib xws, tshwj xeeb tshaj yog txhawb nqa zoo -cov qauv nplej tom qab austenitization.

Txoj Kev Tshawb Nrhiav: Kev soj ntsuam ntawm hom thiab kev faib tawm ntawm cov theem precipitated siv metallographic microscopy + zog dispersive spectroscopy (EDS), thiab kev txiav txim siab raws li qhov ntsuas qhov loj me.

 

3. Kev lees paub ntawm qhov kub siab ruaj khov: kev ntsuas kub thiab kev ntsuas kev ua haujlwm

High-Temperature Holding Test: The material is heated to 900–1100°C, kept for many hours, cooled, and the grain size is measured. The grains do not coarsen much (still >= qib 5) uas qhia tias muaj zog tiv thaiv kev loj hlob ntawm cov nplej.

Creep thiab Durability Strength Test: Tus cwj pwm deformation raug tshawb xyuas nyob rau hauv qhov kub thiab txias loads. Cov ntaub ntawv uas muaj kev tiv thaiv rau cov qoob loo loj hlob zoo li yuav muaj qis dua qis dua thiab lub sijhawm tawg ntev dua.

Thermal Cycling Simulation: Cov qauv no raug rov ua cua sov thiab txias nyob rau hauv simulated kub khiav xwm txheej los soj ntsuam qhov microstructure stability thiab muaj nyob ntawm cov muaju sib xyaw lossis Widmanstätten.

Basic Principple Zener Pinning Effects-Pib theem ob tuaj yeem thaiv lub cev txav ntawm cov ciam teb, uas yog cov txheej txheem tseem ceeb ntawm kev tiv thaiv kev loj hlob ntawm cov nplej.

 

4. Cov txheej txheem xaiv cov khoom siv tswv yim

Nyiam "microalloyed" los yog "intrinsically fine grained" steels (eg, H13+Ti, Al-Killed H13);

Xav kom cov neeg muab khoom siv los muab cov txiaj ntsig kev ntsuas metallographic thiab cov ntawv sib xyaw los tsim cov ntsiab lus ntawm cov ntsiab lus tseem ceeb thiab cov thawj microstructure;

Ua cov qauv kuaj xyuas cov khoom tseem ceeb los tiv thaiv kev siv cov khoom tsis zoo los yog microstructure aberrant.