Kev siv ntau tshaj plaws hauv kev tsim khoom yog qhov nyuaj ntawm kev nias-hauv txoj kev, xws li Brinell hardness, Rockwell hardness, Vickers hardness thiab micro hardness.Qhov tau txais hardness tus nqi tseem ceeb sawv cev rau qhov tsis kam ntawm cov hlau nto rau cov yas deformation los ntawm kev nkag ntawm cov khoom txawv teb chaws.
Cov hauv qab no yog cov lus qhia luv luv rau ntau yam hardness units:
1. Brinell hardness (HB)
Nias lub pob steel ntawm ib qho me me (feem ntau yog 10mm hauv txoj kab uas hla) rau hauv qhov chaw ntawm cov khoom siv nrog ib qho kev thauj khoom (feem ntau 3000kg) thiab khaws cia rau ib lub sijhawm.Tom qab tshem tawm cov load, qhov piv ntawm qhov load mus rau qhov chaw indentation yog Brinell hardness tus nqi (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 ntsuas Rockwell hardness yuav tsum tau siv hloov.Nws siv lub pob zeb diamond lub khob nrog lub kaum sab xis ntawm 120 ° lossis lub pob hlau nrog txoj kab uas hla ntawm 1.59mm thiab 3.18mm los nias rau hauv qhov chaw ntawm cov khoom yuav tsum tau kuaj nyob rau hauv ib tug tej yam load, thiab hardness ntawm cov khoom yog tau los ntawm qhov tob ntawm indentation.Raws li qhov hardness ntawm cov khoom siv kuaj, nws tuaj yeem hais tawm hauv peb qhov sib txawv:
HRA: Nws yog qhov hardness tau los ntawm kev siv 60kg load thiab pob zeb diamond cone indenter, thiab yog siv rau cov ntaub ntawv uas tsis tshua muaj siab hardness (xws li cemented carbide, thiab lwm yam).
HRB: Nws yog lub hardness tau los ntawm kev siv 100kg load thiab hardened steel pob nrog ib txoj kab uas hla ntawm 1.58mm.Nws yog siv rau cov ntaub ntawv nrog qis hardness (xws li annealed steel, cam khwb cia hlau, thiab lwm yam).
HRC: Nws yog lub hardness tau los ntawm kev siv 150kg load thiab pob zeb diamond cone indenter, thiab yog siv rau cov ntaub ntawv uas muaj hardness siab (xws li hardened steel, thiab lwm yam).
3 Vickers hardness (HV)
Siv lub pob zeb diamond square cone indenter nrog lub load tsawg dua 120kg thiab lub vertex lub kaum sab xis ntawm 136 ° los nias rau hauv cov khoom nto, thiab faib qhov chaw ntawm cov khoom indentation qhov chaw los ntawm tus nqi thauj khoom, uas yog Vickers hardness HV tus nqi ( kgf/mm2).
Piv nrog rau Brinell thiab Rockwell hardness tests, Vickers hardness test muaj ntau yam zoo.Nws tsis muaj qhov txwv ntawm cov xwm txheej tshwj xeeb ntawm load P thiab indenter txoj kab uas hla D zoo li Brinell, thiab qhov teeb meem ntawm deformation ntawm indenter;los yog nws tsis muaj teeb meem uas tus nqi hardness ntawm Rockwell tsis tuaj yeem koom ua ke.Thiab nws tuaj yeem kuaj cov ntaub ntawv mos thiab tawv zoo li Rockwell, thiab nws tuaj yeem kuaj qhov tawv ntawm qhov nyias nyias (lossis nyias txheej) zoo dua li Rockwell, uas tsuas yog ua tau los ntawm Rockwell nto hardness.Tab sis txawm nyob rau hauv cov xwm txheej zoo li no, nws tsuas tuaj yeem muab 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 raws li qhov ntsuas ntsuas, thiab qhov indentation qhov tob yog ib txwm me dua qhov dav indentation, yog li nws cov txheeb ze yuam kev kuj loj dua.Yog li ntawd, Rockwell hardness cov ntaub ntawv tsis ruaj khov li Brinell thiab Vickers, thiab ntawm chav kawm tsis ruaj khov li Vickers precision.
Muaj qee qhov kev hloov pauv kev sib raug zoo ntawm Brinell, Rockwell thiab Vickers, thiab muaj cov lus hloov dua siab tshiab uas tuaj yeem nug.
Post lub sij hawm: Mar-16-2023