Qhov siv ntau tshaj plaws hauv kev tsim khoom yog qhov nyuaj ntawm txoj kev nias-hauv, xws li Brinell hardness, Rockwell hardness, Vickers hardness thiab micro hardness. Tus nqi hardness tau txais feem ntau yog qhov tsis kam ntawm cov hlau nto rau cov yas deformation los ntawm kev nkag mus ntawm cov khoom txawv teb chaws.
Cov hauv qab no yog kev qhia luv luv txog ntau yam chav ntsuas qhov nyuaj:
1. Brinell hardness (HB)
Nias lub pob hlau tawv uas muaj qhov loj me (feem ntau yog 10 hli txoj kab uas hla) rau hauv qhov chaw ntawm cov khoom nrog qee qhov hnyav (feem ntau 3000kg) thiab khaws cia rau ib lub sijhawm. Tom qab tshem tawm cov khoom thauj, qhov piv ntawm cov khoom thauj mus rau thaj chaw indentation yog Brinell hardness value (HB), hauv kilogram force / mm2 (N / mm2).
2. Rockwell hardness (HR)
Thaum HB> 450 lossis cov qauv me dhau, Brinell hardness test tsis tuaj yeem siv thiab Rockwell hardness ntsuas yuav tsum tau siv hloov. Nws siv lub pob zeb diamond cone nrog lub kaum sab xis ntawm 120 ° lossis lub pob hlau nrog lub cheeb ntawm 1.59mm thiab 3.18mm los nias rau hauv qhov chaw ntawm cov khoom siv uas yuav tsum tau kuaj hauv qab qee qhov kev thauj khoom, thiab qhov nyuaj ntawm cov khoom siv tau los ntawm qhov tob ntawm qhov indentation. Raws li qhov nyuaj ntawm cov khoom siv kuaj, nws tuaj yeem qhia ua peb qhov sib txawv:
HRA: Nws yog qhov nyuaj tau los ntawm kev siv 60kg thauj khoom thiab lub pob zeb diamond cone indenter, thiab siv rau cov ntaub ntawv uas muaj qhov nyuaj heev (xws li cemented carbide, thiab lwm yam).
HRB: Nws yog qhov nyuaj tau los ntawm kev siv 100kg thauj khoom thiab lub pob hlau tawv nrog txoj kab uas hla ntawm 1.58 hli. Nws yog siv rau cov ntaub ntawv uas muaj qhov nyuaj qis dua (xws li hlau annealed, hlau cam khwb cia, thiab lwm yam).
HRC: Nws yog qhov nyuaj tau los ntawm kev siv 150kg thauj khoom thiab lub pob zeb diamond cone indenter, thiab siv rau cov ntaub ntawv uas muaj qhov nyuaj siab (xws li hlau tawv, thiab lwm yam).
3 Vickers hardness (HV)
Siv lub pob zeb diamond square cone indenter uas muaj qhov hnyav tsawg dua 120kg thiab lub kaum sab xis ntawm 136° los nias rau hauv qhov chaw ntawm cov khoom, thiab faib thaj chaw ntawm qhov chaw ntawm cov khoom los ntawm tus nqi thauj khoom, uas yog Vickers hardness HV tus nqi (kgf/mm2).
Piv nrog rau kev ntsuam xyuas Brinell thiab Rockwell hardness, Vickers hardness test muaj ntau yam zoo. Nws tsis muaj cov kev txwv ntawm cov xwm txheej tshwj xeeb ntawm kev thauj khoom P thiab indenter diameter D zoo li Brinell, thiab qhov teeb meem ntawm kev hloov pauv ntawm indenter; nws tsis muaj teeb meem tias tus nqi hardness ntawm Rockwell tsis tuaj yeem koom ua ke. Thiab nws tuaj yeem sim txhua yam khoom mos thiab tawv zoo li Rockwell, thiab nws tuaj yeem sim qhov nyuaj ntawm cov khoom nyias heev (lossis cov txheej nyias nyias) zoo dua li Rockwell, uas tsuas yog ua tau los ntawm Rockwell qhov nyuaj ntawm qhov chaw. Tab sis txawm tias nyob rau hauv cov xwm txheej zoo li no, nws tsuas yog tuaj yeem piv rau hauv Rockwell nplai, thiab tsis tuaj yeem koom ua ke nrog lwm qib hardness. Tsis tas li ntawd, vim Rockwell siv qhov tob indentation ua qhov ntsuas ntsuas, thiab qhov tob indentation yeej ib txwm me dua qhov dav indentation, yog li nws qhov yuam kev txheeb ze kuj loj dua. Yog li ntawd, cov ntaub ntawv Rockwell hardness tsis ruaj khov li Brinell thiab Vickers, thiab ntawm chav kawm tsis ruaj khov li Vickers precision.
Muaj qee qhov kev hloov pauv ntawm Brinell, Rockwell thiab Vickers, thiab muaj ib daim ntawv teev kev hloov pauv uas tuaj yeem nug tau.
Lub sijhawm tshaj tawm: Lub Peb Hlis-16-2023
