Ukukwazi kwezinto zetsimbi ukuxhathisa ukunyanzeliswa komphezulu ngezinto ezinzima kubizwa ngokuba lukhuni. Ngokweendlela ezahlukeneyo zovavanyo kunye nobubanzi besicelo, ubulukhuni bunokwahlulwa bubulukhuni beBrinell, ukuqina kweRockwell, ukuqina kweVickers, ukuqina konxweme, ubulukhuni obuncinci kunye nobunzima obuphezulu bobushushu. Kukho ubulukhuni obuthathu obusetyenziswa ngokuqhelekileyo kwimibhobho: iBrinell, Rockwell, kunye nokuqina kweVickers.
A. Ukuqina kweBrinell (HB)
Sebenzisa ibhola yentsimbi okanye ibhola ye-carbide yobubanzi obuthile ukucinezela kwindawo yesampulu kunye novavanyo oluchaziweyo lwamandla (F). Emva kwexesha elichaziweyo lokubamba, susa amandla okuvavanya kwaye ulinganise i-indentiation diameter (L) kumphezulu wesampuli. Ixabiso le-Brinell hardness yi-quotient efunyenwe ngokwahlula amandla ovavanyo ngomphezulu wendawo ye-indented sphere. Icaciswe kwi-HBS (ibhola yentsimbi), iyunithi yi-N/mm2 (MPa).
Ifomula yokubala yile:
Kwifomula: F–amandla ovavanyo acinezelwe kumphezulu wesampulu yesinyithi, N;
I-D-Diameter yebhola yentsimbi yokuvavanya, mm;
d–i-avareji yedayamitha yokuhlenga-hlengisa, mm.
Umlinganiselo wobunzima beBrinell uchaneke ngakumbi kwaye unokwethenjelwa, kodwa ngokuqhelekileyo i-HBS ifaneleka kuphela kwizinto zetsimbi ezingaphantsi kwe-450N / mm2 (MPa), kwaye ayifanelekanga kwintsimbi eqinile okanye iipleyiti ezincinci. Phakathi kwemigangatho yemibhobho yentsimbi, ukuqina kweBrinell yeyona nto isetyenziswa kakhulu. Idayamitha ye-indentation d isoloko isetyenziselwa ukubonisa ubulukhuni bemathiriyeli, eqondakalayo kwaye ifanelekile.
Umzekelo: 120HBS10/1000130: Kuthetha ukuba ixabiso lobulukhuni beBrinell elilinganiswa ngokusebenzisa ibhola yensimbi ye-10mm ububanzi phantsi kovavanyo lwamandla e-1000Kgf (9.807KN) kuma-30s (imizuzwana) yi-120N/mm2 (MPa).
B. Ukuqina kweRockwell (HR)
Uvavanyo lobulukhuni be-Rockwell, njengovavanyo lobulukhuni be-Brinell, yindlela yovavanyo lokungeniswa. Umahluko kukuba ilinganisa ubunzulu be-indent. Oko kukuthi, phantsi kwesenzo sokulandelelana kwamandla ovavanyo lokuqala (Fo) kunye novavanyo olupheleleyo lwamandla (F), i-indenter (i-cone okanye ibhola yensimbi yentsimbi yensimbi) icinezelwe kumphezulu wesampuli. Emva kwexesha elichaziweyo lokubamba, amandla aphambili ayasuswa. Amandla ovavanyo, sebenzisa umlinganiselo wentsalela wobunzulu bobunzulu bokwenyuka (e) ukubala ixabiso lobulukhuni. Ixabiso layo linani elingaziwa, elimelwe yi-symbol HR, kwaye izikali ezisetyenzisiweyo zibandakanya izikali ze-9, ezibandakanya i-A, B, C, D, E, F, G, H, kunye no-K. Phakathi kwazo, izikali eziqhelekileyo ezisetyenziselwa ukuvavanya ubulukhuni bensimbi ngokuqhelekileyo ziyi-A, B, kunye ne-C, ezizezi, i-HRA, i-HRB, kunye ne-HRC.
Ixabiso lobulukhuni libalwa kusetyenziswa le fomula ilandelayo:
Xa uvavanya ngezikali zika-A no-C, HR=100-e
Xa uvavanya ngesikali B, HR=130-e
Kwifomula, u-e - ukunyuswa kobunzulu obushiyekileyo buchazwa kwiyunithi echaziweyo ye-0.002mm, oko kukuthi, xa i-axial displacement ye-indenter iyunithi enye (0.002mm), ilingana nokutshintsha kobunzima be-Rockwell ngenani elinye. Ixabiso elikhulu le-e, lisezantsi ubulukhuni besinyithi, kwaye ngokuphambeneyo.
Umda osebenzayo wezikali zintathu zingasentla umi ngolu hlobo lulandelayo:
HRA (diamond cone indenter) 20-88
HRC (diamond cone indenter) 20-70
I-HRB (ububanzi be-1.588mm ibhola yensimbi) 20-100
Uvavanyo lobulukhuni be-Rockwell yindlela esetyenziswa ngokubanzi ngoku, phakathi kwayo i-HRC isetyenziswa kwimigangatho yentsimbi yombhobho okwesibini kuphela kwi-Brinell ubulukhuni be-HB. Ubunzima beRockwell bunokusetyenziselwa ukulinganisa imathiriyeli yentsimbi ukusuka ekuthambileyo kakhulu ukuya kokuqina kakhulu. Yenza ukusilela kwendlela yeBrinell. Ilula kunendlela yeBrinell kunye nexabiso lobunzima linokufundwa ngokuthe ngqo kwi-dial yomshini wobunzima. Nangona kunjalo, ngenxa ye-indentation yayo encinci, ixabiso lobunzima alichanekanga njengendlela yeBrinell.
C. Vickers ubunzima (HV)
Uvavanyo lobulukhuni beVickers lukwayindlela yovavanyo lokungeniswa. Icinezela i-indenter yedayimane yephiramidi ene-engile equkiweyo ye-1360 phakathi kweendawo ezichaseneyo kwindawo yovavanyo kumandla ovavanyo akhethiweyo (F), kwaye iyisuse emva kwexesha elichaziweyo lokubamba. Nyanza, yenza umlinganiselo wobude beediagonal ezimbini zokuhlenga-hlengisa.
Ixabiso lobulukhuni beVickers yi-quotient yovavanyo lwamandla olwahlulwe ngummandla wokungeniswa komphezulu. Ifomula yayo yokubala yile:
Kwifomula: HV–Vickers isimboli yobulukhuni, N/mm2 (MPa);
F-amandla ovavanyo, N;
d–intsingiselo ye-arithmetic yeediagonal ezimbini ze-indentation, mm.
I-test force F esetyenziswe kwi-Vickers ubulukhuni yi-5 (49.03), 10 (98.07), 20 (196.1), 30 (294.2), 50 (490.3), 100 (980.7) Kgf (N) kunye namanye amanqanaba amathandathu. Ixabiso lobunzima linokulinganiswa Uluhlu luyi-5 ~ 1000HV.
Umzekelo wendlela yokubonakalisa: 640HV30/20 ithetha ukuba ixabiso lobulukhuni beVickers elilinganiswe ngamandla ovavanyo lwe-30Hgf (294.2N) ye-20S (imizuzwana) yi-640N/mm2 (MPa).
Indlela yokuqina yeVickers ingasetyenziselwa ukumisela ukuqina kwemathiriyeli yesinyithi ecekeceke kakhulu kunye namaleko angaphezulu. Ineenzuzo eziphambili zeBrinell kunye neendlela zeRockwell kwaye zinqoba iintsilelo zabo ezisisiseko, kodwa ayilula njengendlela ye-Rockwell. Indlela yeVickers ayifane isetyenziswe kwimigangatho yepayipi yensimbi.
Ixesha lokuposa: Apr-03-2024