ʻO ka hiki o kahi mea metala ke kū'ē i ka indentation o ka ʻili e nā mea paʻakikī ua kapa ʻia ʻo ia he paʻakikī. Wahi a nā ʻano hoʻāʻo like ʻole a me ka laulā o ka noi, hiki ke hoʻokaʻawale ʻia ka paʻakikī i ka paʻakikī Brinell, ka paʻakikī Rockwell, ka paʻakikī Vickers, ka paʻakikī Shore, ka paʻakikī micro a me ka paʻakikī wela kiʻekiʻe. ʻEkolu mau paʻakikī i hoʻohana pinepine ʻia no nā paipu: ʻo Brinell, Rockwell, a me Vickers hardness.
A. Paʻakikī Brinell (HB)
E hoʻohana i kahi pōpō kila a i ʻole ka pōpō carbide o kekahi anawaena e kaomi i loko o ka ʻili laʻana me ka ikaika hoʻāʻo i kuhikuhi ʻia (F). Ma hope o ka manawa paʻa i kuhikuhi ʻia, e wehe i ka ikaika hoʻāʻo a ana i ke anawaena indentation (L) ma ka ʻili laʻana. ʻO ka waiwai paʻakikī Brinell ka quotient i loaʻa ma ka puʻunaue ʻana i ka ikaika hoʻāʻo ma ka ʻāpana ʻili o ka sphere indented. I hōʻike ʻia ma HBS (pōpō kila), ʻo ke anakahi ʻo N/mm2 (MPa).
ʻO ke ʻano helu:
Ma ke ʻano haʻilula: F–ka ikaika hoʻāʻo i kaomi ʻia i loko o ka ʻili o ka hāpana metala, N;
D–Ke anawaena o ka pōpō kila no ka hoʻāʻo ʻana, mm;
d–ʻawelike ke anawaena o ke komo ʻana, mm.
ʻOi aku ka pololei a me ka hilinaʻi o ke ana ʻana o ka paʻakikī Brinell, akā ma ke ʻano laulā, kūpono wale ʻo HBS no nā mea metala ma lalo o 450N/mm2 (MPa), a ʻaʻole kūpono no ke kila paʻakikī a i ʻole nā papa lahilahi. Ma waena o nā kūlana paipu kila, ʻo ka paʻakikī Brinell ka mea i hoʻohana nui ʻia. Hoʻohana pinepine ʻia ke anawaena indentation d e hōʻike i ka paʻakikī o ka mea, he mea maʻalahi a maʻalahi hoʻi.
Laʻana: 120HBS10/1000130: ʻO ia hoʻi, ʻo ka waiwai paʻakikī Brinell i ana ʻia ma ka hoʻohana ʻana i kahi pōpō kila 10mm ke anawaena ma lalo o ka ikaika hoʻāʻo o 1000Kgf (9.807KN) no 30s (kekona) he 120N/mm2 (MPa).
B. Paʻakikī Rockwell (HR)
ʻO ka hoʻāʻo paʻakikī Rockwell, e like me ka hoʻāʻo paʻakikī Brinell, he ʻano hoʻāʻo indentation. ʻO ka ʻokoʻa, ʻo ia ke ana ʻana i ka hohonu o ka indentation. ʻO ia hoʻi, ma lalo o ka hana kaʻina o ka ikaika hoʻāʻo mua (Fo) a me ka ikaika hoʻāʻo holoʻokoʻa (F), ua kaomi ʻia ka indenter (cone a i ʻole ka pōpō kila o ka wili kila) i loko o ka ʻili o ka laʻana. Ma hope o ka manawa paʻa i kuhikuhi ʻia, ua wehe ʻia ka ikaika nui. Hoʻāʻo ikaika, e hoʻohana i ka hoʻonui hohonu indentation koena i ana ʻia (e) e helu i ka waiwai paʻakikī. ʻO kona waiwai he helu inoa ʻole, i hōʻike ʻia e ka hōʻailona HR, a ʻo nā unahi i hoʻohana ʻia he 9 mau unahi, me A, B, C, D, E, F, G, H, a me K. I waena o lākou, ʻo nā unahi i hoʻohana pinepine ʻia no ka hoʻāʻo paʻakikī kila ʻo A, B, a me C, ʻo ia hoʻi ʻo HRA, HRB, a me HRC.
Ua helu ʻia ka waiwai paʻakikī me ka hoʻohana ʻana i kēia ʻano hana:
I ka hoʻāʻo ʻana me nā unahi A a me C, HR=100-e
I ka hoʻāʻo ʻana me ka unahi B, HR=130-e
Ma ke ʻano haʻilula, e - ua hōʻike ʻia ka hoʻonui hohonu indentation koena ma ke anakahi i kuhikuhi ʻia o 0.002mm, ʻo ia hoʻi, i ka wā e hoʻokahi anakahi (0.002mm) ka neʻe ʻana o ka axial o ka indenter, ua like ia me ka loli o ka paʻakikī Rockwell e hoʻokahi helu. ʻO ka nui o ka waiwai e, ʻo ka haʻahaʻa o ka paʻakikī o ka metala, a ʻo ka hope.
ʻO ka laulā kūpono o nā unahi ʻekolu i luna penei:
HRA (mea hoʻokomo ʻōniʻoniʻo daimana) 20-88
HRC (mea hoʻokomo ʻōniʻoniʻo daimana) 20-70
HRB (ʻāpana pōpō kila anawaena 1.588mm) 20-100
ʻO ka hoʻāʻo paʻakikī ʻo Rockwell kahi ʻano hana i hoʻohana nui ʻia i kēia manawa, ma waena o ia mea i hoʻohana ʻia ai ʻo HRC i nā kūlana paipu kila ʻelua wale nō ma hope o ka paʻakikī ʻo Brinell HB. Hiki ke hoʻohana ʻia ka paʻakikī ʻo Rockwell e ana i nā mea metala mai ka palupalu loa a i ka paʻakikī loa. Hoʻopiha ia i nā hemahema o ke ʻano Brinell. ʻOi aku ka maʻalahi ma mua o ke ʻano Brinell a hiki ke heluhelu pololei ʻia ka waiwai paʻakikī mai ka dial o ka mīkini paʻakikī. Eia naʻe, ma muli o kona indentation liʻiliʻi, ʻaʻole pololei ka waiwai paʻakikī e like me ke ʻano Brinell.
C. Paʻakikī Vickers (HV)
ʻO ka hoʻāʻo paʻakikī Vickers he ʻano hoʻāʻo indentation nō hoʻi. Hoʻokomo ia i kahi indenter daimana pyramidal huinaha me kahi kihi i hoʻokomo ʻia o 1360 ma waena o nā ʻili kū'ē i loko o ka ʻili hoʻāʻo ma kahi ikaika hoʻāʻo i koho ʻia (F), a wehe iā ia ma hope o ka manawa paʻa i kuhikuhi ʻia. Ikaika, e ana i ka lōʻihi o nā diagonals ʻelua o ka indentation.
ʻO ka waiwai paʻakikī Vickers ka quotient o ka ikaika hoʻāʻo i puʻunaue ʻia e ka ʻāpana ʻili indentation. ʻO kāna ʻano helu:
Ma ke ʻano haʻilula: hōʻailona paʻakikī HV–Vickers, N/mm2 (MPa);
Ka ikaika hoʻāʻo F, N;
d–ka awelika helu o nā diagonals ʻelua o ke kaha komo ʻana, mm.
ʻO ka ikaika hoʻāʻo F i hoʻohana ʻia ma ka paʻakikī Vickers he 5 (49.03), 10 (98.07), 20 (196.1), 30 (294.2), 50 (490.3), 100 (980.7) Kgf (N) a me nā pae ʻeono ʻē aʻe. Hiki ke ana ʻia ka waiwai paʻakikī. ʻO ka laulā he 5 ~ 1000HV.
Laʻana o ke ʻano hōʻike: ʻO 640HV30/20 ke ʻano o ka waiwai paʻakikī Vickers i ana ʻia me ka ikaika hoʻāʻo o 30Hgf (294.2N) no 20S (kekona) he 640N/mm2 (MPa).
Hiki ke hoʻohana ʻia ke ʻano paʻakikī Vickers e hoʻoholo ai i ka paʻakikī o nā mea metala lahilahi loa a me nā papa ʻili. Loaʻa iā ia nā pono nui o nā ʻano Brinell lāua ʻo Rockwell a lanakila i ko lākou mau hemahema kumu, akā ʻaʻole ia he maʻalahi e like me ke ʻano Rockwell. ʻAʻole hoʻohana pinepine ʻia ke ʻano Vickers i nā kūlana paipu kila.
Ka manawa hoʻouna: ʻApelila-03-2024
