Ua hōʻoia ʻoe ua hana ʻia nā ʻāpana e like me nā kikoʻī. I kēia manawa e hōʻoia e hana ʻoe i nā hana e pale aku i kēia mau ʻāpana i ke kaiapuni e manaʻo ai kāu poʻe kūʻai. #base
He mea nui ka passivation i ka hoʻonui ʻana i ke kūpaʻa ʻana i ka pala o nā ʻāpana a me nā ʻākoakoa i hana ʻia mai ke kila kila. Hiki i kēia ke hana i ka ʻokoʻa ma waena o ka hana kūpono a me ka hāʻule mua ʻana. Hiki i ka passivation hewa ke hana i ka pala.
ʻO ka passivation kahi hana ma hope o ka hana ʻana e hoʻonui ai i ke kūpaʻa kūlohelohe o nā mea kila kila kila mai kahi i hana ʻia ai ka mea hana. ʻAʻole kēia he descaling a pena paha.
ʻAʻohe manaʻo like e pili ana i ke ʻano hana pololei o ka passivation. Akā ua ʻike maopopo ʻia aia kahi ʻili oxide pale ma luna o ka ʻili o ke kila kila i passivated. Ua ʻōlelo ʻia he lahilahi loa kēia ʻili ʻike ʻole ʻia, ʻaʻole i emi ma mua o 0.0000001 ʻīniha ka mānoanoa, ʻo ia hoʻi ma kahi o 1/100,000 ka mānoanoa o ka lauoho kanaka!
ʻO kahi ʻāpana kila kila maʻemaʻe, i hana hou ʻia, i hoʻopili ʻia, a i ʻole i hoʻomoʻa ʻia e loaʻa koke i kēia ʻili oxide ma muli o ka ʻike ʻia ʻana i ka oxygen lewa. Ma lalo o nā kūlana kūpono, uhi piha kēia papa oxide pale i nā ʻili āpau o ka ʻāpana.
Eia nō naʻe, i ka hana maoli, hiki i nā mea haumia e like me ka lepo o ka hale hana a i ʻole nā ​​ʻāpana hao mai nā mea ʻokiʻoki ke kau ma luna o nā ʻāpana kila kila i ka wā e hana ai. Inā ʻaʻole e wehe ʻia, hiki i kēia mau kino haole ke hōʻemi i ka pono o ka ʻili pale mua.
I ka wā o ka mīkini ʻana, hiki ke wehe ʻia nā koena o ka hao manuahi mai ka mea hana a hoʻoili ʻia i ka ʻili o ka mea hana kila kila. I kekahi mau hihia, hiki ke ʻike ʻia kahi papa lahilahi o ka popo ma ka ʻāpana. ʻO ka ʻoiaʻiʻo, ʻo ia ka pala o ke kila mea hana, ʻaʻole ka metala kumu. I kekahi manawa hiki i nā māwae mai nā ʻāpana kila i hoʻokomo ʻia mai nā mea hana ʻoki a i ʻole kā lākou huahana pala ke hoʻopau i ka ʻāpana ponoʻī.
Pēlā nō, hiki i nā ʻāpana liʻiliʻi o ka lepo hao hao ke pipili i ka ʻili o ka ʻāpana. ʻOiai ke ʻano ʻālohilohi o ka metala i kona kūlana i pau ai, ma hope o ka ʻike ʻia ʻana i ka ea, hiki i nā ʻāpana hao ʻike ʻole ʻia ke hana i ka popo o ka ʻili.
Hiki i nā sulfides i hōʻike ʻia ke lilo i pilikia. Hana ʻia lākou ma ka hoʻohui ʻana i ka sulfur i ke kila kila e hoʻomaikaʻi i ka mīkini. Hoʻonui nā sulfides i ka hiki o ka alloy ke hana i nā ʻāpana i ka wā o ka mīkini ʻana, hiki ke wehe loa ʻia mai ka mea ʻoki. Inā ʻaʻole i passivated pono nā ʻāpana, hiki i nā sulfides ke lilo i wahi hoʻomaka no ka palaho o ka ʻili o nā huahana ʻoihana.
I nā hihia ʻelua, pono ka passivation e hoʻonui i ke kūpaʻa kūlohelohe o ke kila kila. Hoʻopau ia i nā mea haumia o ka ʻili e like me nā ʻāpana hao a me nā ʻāpana hao i nā mea ʻokiʻoki e hiki ke hana i ka popo a lilo paha i kumu hoʻomaka no ka pala. Hoʻopau pū ka passivation i nā sulfides i loaʻa ma ka ʻili o nā mea hao kila kila ʻoki hāmama.
Hāʻawi ke kaʻina hana ʻelua ʻanuʻu i ke kūpaʻa maikaʻi loa i ka pala: 1. Hoʻomaʻemaʻe, ke kaʻina hana nui, akā i kekahi manawa hoʻowahāwahā ʻia 2. ʻAuʻau ʻakika a passivation paha.
Pono ka hoʻomaʻemaʻe ʻana i mea nui mau. Pono e hoʻomaʻemaʻe pono ʻia nā ʻili mai ka momona, ka mea hoʻomaʻalili a i ʻole nā ​​​​​​ʻōpala ʻē aʻe e hōʻoia i ka pale ʻana i ka pala. Hiki ke holoi mālie ʻia nā ʻōpala mīkini a i ʻole ka lepo hale hana ʻē aʻe mai ka ʻāpana. Hiki ke hoʻohana ʻia nā mea hoʻomaʻemaʻe a i ʻole nā ​​​​​​mea hoʻomaʻemaʻe kalepa e wehe i nā aila hana a i ʻole nā ​​​​​​mea hoʻomaʻalili. Pono paha e wehe ʻia nā mea ʻē e like me nā oxides thermal ma o nā ʻano hana e like me ka wili ʻana a i ʻole ka pickling.
I kekahi manawa, e hōʻalo paha ka mea hoʻohana mīkini i ka hoʻomaʻemaʻe maʻamau, me ka manaʻo kuhihewa e hana ʻia ka hoʻomaʻemaʻe a me ka passivation i ka manawa like, ma ka hoʻoluʻu wale ʻana i ka ʻāpana i aila ʻia i loko o kahi ʻauʻau waikawa. ʻAʻole ia e hana. I ka ʻaoʻao ʻē aʻe, hana ka momona haumia me ka waikawa e hana i nā pehu ea. Hōʻiliʻili kēia mau pehu ma luna o ka ʻili o ka mea hana a hoʻopilikia i ka passivation.
ʻOi aku ka ʻino, ʻo ka haumia o nā hopena passivation, kahi i loaʻa i kekahi manawa nā chlorides kiʻekiʻe, hiki ke hana i kahi "flash". I ka hoʻohālikelike ʻana i ka hana ʻana i ka ʻili oxide i makemake ʻia me kahi ʻili ʻālohilohi, maʻemaʻe, a kū i ka corrosion, hiki i ka flash etching ke hopena i ka etching koʻikoʻi a i ʻole ka ʻeleʻele o ka ʻili - kahi ʻino i ka ʻili i hoʻolālā ʻia e hoʻomaikaʻi i ka passivation.
Hoʻopau ʻia nā ʻāpana kila kila Martensitic [magnetic, pale ʻino kūpono, ikaika hua a hiki i kahi 280 tausani psi (1930 MPa)] i nā mahana kiʻekiʻe a laila hoʻomaʻamaʻa ʻia e hāʻawi i ka paʻakikī i makemake ʻia a me nā waiwai mechanical. Hiki ke mālama ʻia nā mea hoʻohuihui paʻakikī (ʻoi aku ka ikaika a me ke kūpaʻa ʻana i ka pala ma mua o nā māka martensitic) i ka hopena, mīkini hapa, ʻelemakule i nā mahana haʻahaʻa, a laila hoʻopau.
I kēia hihia, pono e hoʻomaʻemaʻe pono ʻia ka ʻāpana me kahi degreaser a mea hoʻomaʻemaʻe paha ma mua o ka mālama ʻana i ka wela e wehe i kekahi koena o ka wai ʻoki. A i ʻole, hiki i ka coolant e waiho ana ma ka ʻāpana ke hana i ka oxidation nui. Hiki i kēia kūlana ke hana i nā decks ma nā ʻāpana liʻiliʻi ma hope o ka descaling me nā ʻano waikawa a i ʻole abrasive. Inā waiho ʻia ka coolant ma nā ʻāpana paʻakikī ʻālohilohi, e like me ka umu vacuum a i ʻole i loko o kahi lewa pale, hiki ke hana ʻia ka carburization o ka ʻili, e hopena ana i ka nalowale o ke kūpaʻa ʻana i ka corrosion.
Ma hope o ka hoʻomaʻemaʻe pono ʻana, hiki ke hoʻokomo ʻia nā ʻāpana kila kila i loko o kahi ʻauʻau waikawa passivating. Hiki ke hoʻohana ʻia kekahi o nā ʻano hana ʻekolu - passivation me ka waikawa nitric, passivation me ka waikawa nitric me ka sodium dichromate, a me passivation me ka waikawa citric. ʻO ke ʻano hana e hoʻohana ai ma muli o ke ʻano o ke kila kila a me nā pae hoʻomaopopo i kuhikuhi ʻia.
Hiki ke hoʻopau ʻia nā papa nickel chromium kūpaʻa i ka palaho i loko o kahi ʻauʻau waikawa nitric 20% (v/v) (Kiʻi 1). E like me ka mea i hōʻike ʻia ma ka papa ʻaina, hiki ke hoʻopau ʻia nā kila kila kūpaʻa ʻole ma ka hoʻohui ʻana i ka sodium dichromate i kahi ʻauʻau o ka waikawa nitric e hoʻolilo i ka hopena i ʻoi aku ka oxidizing a hiki ke hana i kahi kiʻi passivating ma luna o ka ʻili metala. ʻO kekahi koho no ka hoʻololi ʻana i ka waikawa nitric me ka sodium chromate ʻo ia ka hoʻonui ʻana i ka nui o ka waikawa nitric i 50% ma ka nui. ʻO ka hoʻohui ʻana o ka sodium dichromate a me ke kiʻekiʻe o ka nui o ka waikawa nitric e hōʻemi ana i ka hiki ke loaʻa kahi flash i makemake ʻole ʻia.
ʻOkoʻa iki ke kaʻina hana passivation no nā kila kila hiki ke mīkini ʻia (i hōʻike ʻia ma ke Kiʻi 1) mai ke kaʻina hana no nā papa kila kila hiki ʻole ke mīkini ʻia. ʻO kēia no ka mea i ka wā passivation i loko o kahi ʻauʻau waikawa nitric ua wehe ʻia kekahi a i ʻole nā ​​​​sulfides i loaʻa ka sulfur hiki ke mīkini ʻia, e hana ana i nā inhomogeneities microscopic ma ka ʻili o ka workpiece.
ʻOiai ka holoi wai maikaʻi maʻamau hiki ke waiho i ke koena waikawa i loko o kēia mau discontinuities ma hope o ka passivation. E hoʻouka kēia waikawa i ka ʻili o ka ʻāpana inā ʻaʻole i hoʻopau ʻia a wehe ʻia paha.
No ka passivation kūpono o ke kila kila maʻalahi e mīkini, ua hoʻomohala ʻo Carpenter i ke kaʻina hana AAA (Alkaline-Acid-Alkaline), kahi e hoʻopau ai i ke koena waikawa. Hiki ke hoʻopau ʻia kēia ʻano passivation ma lalo o 2 mau hola. Eia ke kaʻina hana ʻanuʻu:
Ma hope o ka hoʻohemo ʻana i ka ʻaila, e hoʻomohu i nā ʻāpana i loko o ka hopena sodium hydroxide 5% ma 160°F a i 180°F (71°C a i 82°C) no 30 mau minuke. A laila holoi pono i nā ʻāpana i loko o ka wai. A laila e hoʻoluʻu i ka ʻāpana no 30 mau minuke i loko o kahi hopena waikawa nitric 20% (v/v) e loaʻa ana he 3 oz/gal (22 g/l) sodium dichromate ma 120°F a i 140°F (49°C) a i 60°C. ) Ma hope o ka wehe ʻana i ka ʻāpana mai ka ʻauʻau, holoi me ka wai, a laila e hoʻoluʻu i loko o kahi hopena sodium hydroxide no 30 mau minuke. E holoi hou i ka ʻāpana me ka wai a hoʻomaloʻo, e hoʻopau ana i ke ʻano AAA.
Ke lilo nei ka passivation waikawa citric i mea kaulana i waena o nā mea hana e makemake ana e pale i ka hoʻohana ʻana i nā waikawa mineral a i ʻole nā ​​​​​​mea hoʻonā i loaʻa ka sodium dichromate, a me nā pilikia hoʻolei a me ka hoʻonui ʻia o nā hopohopo palekana e pili ana i kā lākou hoʻohana. Ua manaʻo ʻia he launa maikaʻi ke kaiapuni i nā ʻano āpau.
ʻOiai ʻo ka passivation waikawa citric e hāʻawi ana i nā pono kaiapuni hoihoi, ʻo nā hale kūʻai i kūleʻa me ka passivation waikawa inorganic a ʻaʻohe hopohopo palekana e makemake paha e noho i ke ala. Inā he hale kūʻai maʻemaʻe kēia mau mea hoʻohana, aia nā lako i ke kūlana maikaʻi a maʻemaʻe, ʻaʻohe waihona ferrous o ka hale hana i ka coolant, a ke hana nei ke kaʻina hana i nā hopena maikaʻi, ʻaʻole paha he pono maoli no ka hoʻololi.
Ua ʻike ʻia he mea pono ka passivation ʻauʻau citric acid no nā ʻano kila kila like ʻole, me kekahi mau papa kila kila like ʻole, e like me ka mea i hōʻike ʻia ma ke Kiʻi 2. No ka maʻalahi, ua hoʻokomo pū ʻia ke Kiʻi 2.1 i ke ʻano kuʻuna o ka passivation me ka waikawa nitric. E hoʻomaopopo ʻia ua hōʻike ʻia nā ʻano waikawa nitric kahiko ma ke ʻano he pakeneka ma ka nui, ʻoiai ua hōʻike ʻia nā ʻano waikawa citric hou ma ke ʻano he pakeneka ma ke kaumaha. He mea nui e hoʻomaopopo i ka wā e hana ai i kēia mau kaʻina hana, he mea nui ka kaulike akahele o ka manawa hoʻomohu, ka mahana ʻauʻau, a me ka noʻonoʻo ʻana e pale aku i ka "ʻālohilohi" i wehewehe ʻia ma luna.
ʻOkoʻa ka passivation ma muli o ka nui o ka chromium a me nā ʻano hana o kēlā me kēia ʻano. E nānā i nā kolamu no ke Kaʻina Hana 1 a i ʻole ke Kaʻina Hana 2. E like me ka mea i hōʻike ʻia ma ke Kiʻi 3, ʻoi aku ka liʻiliʻi o nā ʻanuʻu o ke Kaʻina Hana 1 ma mua o ke Kaʻina Hana 2.
Ua hōʻike ʻia nā hoʻokolohua hale hana he ʻoi aku ka maʻalahi o ke kaʻina hana passivation citric acid i ka "paila" ma mua o ke kaʻina hana nitric acid. ʻO nā mea e kōkua ana i kēia hoʻouka kaua ʻana, ʻo ia ka mahana ʻauʻau kiʻekiʻe loa, ka manawa hoʻomoʻa lōʻihi loa, a me ka haumia ʻauʻau. Loaʻa nā huahana i hana ʻia me ka citric acid i loaʻa nā mea pale i ka corrosion a me nā mea hoʻohui ʻē aʻe e like me nā mea hoʻomaʻū a ua hōʻike ʻia e hōʻemi i ka hiki ke "flash corrosion".
ʻO ke koho hope loa o ke ʻano passivation e pili ana i nā pae ʻae i hoʻonohonoho ʻia e ka mea kūʻai aku. E ʻike iā ASTM A967 no nā kikoʻī. Hiki ke kiʻi ʻia ma www.astm.org.
Hoʻokō pinepine ʻia nā hoʻāʻo e loiloi i ka ʻili o nā ʻāpana passivated. ʻO ka nīnau e pane ʻia, "Hoʻopau anei ka passivation i ka hao manuahi a hoʻonui i ke kūpaʻa ʻana o ka corrosion o nā alloys no ka ʻoki ʻakomi?"
He mea nui e kūlike ke ʻano hoʻāʻo me ka papa e loiloi ʻia ana. ʻAʻole e hala nā hoʻāʻo paʻakikī loa i nā mea maikaʻi loa, ʻoiai ʻo nā hoʻāʻo nāwaliwali loa e hala i nā ʻāpana ʻoluʻolu ʻole.
ʻOi aku ka maikaʻi o ka loiloi ʻana i nā kila kila kila PH a me ka maʻalahi o ka mīkini ʻana o 400 series i loko o kahi keʻena i hiki ke mālama i ka 100% humidity (laʻana pulu) no 24 mau hola ma 95°F (35°C). ʻO ka ʻāpana kea ka ʻili koʻikoʻi loa, ʻoi aku hoʻi no nā māka ʻoki manuahi. ʻO kekahi kumu no kēia, ʻo ia ka huki ʻia ʻana o ka sulfide i ke kuhikuhi mīkini ma kēia ʻili.
Pono e kau ʻia nā ʻili koʻikoʻi i luna, akā ma ke kihi o 15 a 20 degere mai ke kū pololei, i mea e ʻae ai i ka nalowale ʻana o ka makū. ʻAʻole e popo ka mea i hoʻoneʻe pono ʻia, ʻoiai e ʻike ʻia paha nā kiko liʻiliʻi ma luna.
Hiki ke loiloi ʻia nā pae kila kila Austenitic ma o ka hoʻāʻo ʻana i ka makū. Ma kēia hoʻāʻo, pono e loaʻa nā kulu wai ma luna o ka ʻili o ka laʻana, e hōʻike ana i ka hao manuahi ma ke alo o kekahi ʻōpala.
Pono nā kaʻina hana passivation no nā kila kila kila a me nā kila lima i hoʻohana pinepine ʻia i nā hopena citric a i ʻole nitric acid i nā kaʻina hana like ʻole. Ma ke kiʻi 3 ma lalo nei hāʻawi i nā kikoʻī e pili ana i ke koho ʻana i ke kaʻina hana.
(a) E hoʻoponopono i ka pH me ka sodium hydroxide. (b) E nānā i ke kiʻi 3(c) ʻO Na2Cr2O7 he 3 oz/gal (22 g/L) sodium dichromate i loko o 20% nitric acid. ʻO kahi koho ʻē aʻe i kēia hui ʻana he 50% nitric acid me ka ʻole o ka sodium dichromate.
ʻO kahi ala wikiwiki e hoʻohana ai iā ASTM A380, Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems. Hoʻokomo pū ka hoʻāʻo ʻana i ka holoi ʻana i ka ʻāpana me kahi hopena keleawe sulfate/sulfuric acid, e mālama ana iā ia i ka pulu no 6 mau minuke, a me ka nānā ʻana i ke kāpili keleawe. A i ʻole, hiki ke hoʻokomo ʻia ka ʻāpana i loko o ka hopena no 6 mau minuke. Inā heheʻe ka hao, hana ʻia ke kāpili keleawe. ʻAʻole pili kēia hoʻāʻo i nā ʻili o nā ʻāpana hana meaʻai. Eia kekahi, ʻaʻole pono e hoʻohana ʻia ma nā kila martensitic 400 series a i ʻole nā ​​​​kila ferritic chromium haʻahaʻa no ka mea hiki ke loaʻa nā hopena maikaʻi ʻole.
I ka wā ma mua, ua hoʻohana ʻia ka hoʻāʻo pīpī paʻakai 5% ma 95°F (35°C) e loiloi i nā laʻana passivated. He paʻakikī loa kēia hoʻāʻo no kekahi mau cultivars a ʻaʻole pono ia e hōʻoia i ka pono o ka passivation.
E hōʻalo i ka hoʻohana ʻana i nā chloride keu, kahi e hiki ai ke hoʻoulu i nā lapalapa weliweli. E hoʻohana wale i ka wai kiʻekiʻe me ka emi ma mua o 50 mau ʻāpana i ka miliona (ppm) chloride i nā manawa hiki. ʻO ka wai piula wai ka mea maʻamau, a i kekahi mau hihia hiki iā ia ke kū i kekahi mau haneli ʻāpana i ka miliona o nā chloride.
He mea nui e hoʻololi pinepine i ka ʻauʻau i ʻole e nalowale ka hiki ke passivation, hiki ke alakaʻi i nā hahau uila a me ka hōʻino ʻana i nā ʻāpana. Pono e mālama ʻia ka ʻauʻau i ka mahana kūpono, no ka mea, hiki i nā mahana i kāohi ʻole ʻia ke hana i ka pala kūloko.
He mea nui e hahai i kahi papa hana hoʻololi hoʻonā kikoʻī loa i ka wā o ka hana nui ʻana e hōʻemi i ka hiki ke haumia. Ua hoʻohana ʻia kahi hāpana kaohi e hoʻāʻo i ka pono o ka ʻauʻau. Inā ua hoʻouka ʻia ka hāpana, ua hiki i ka manawa e hoʻololi i ka ʻauʻau.
E ʻoluʻolu e hoʻomaopopo he hana wale kekahi mau mīkini i ke kila kila; e hoʻohana i ka mea hoʻoluʻu makemake like no ka ʻoki ʻana i ke kila kila me ka hoʻokaʻawale ʻana i nā metala ʻē aʻe a pau.
Hoʻokaʻawale ʻia nā ʻāpana DO rack e pale aku i ka hoʻopili ʻana o ka metala i ka metala. He mea nui loa kēia no ka mīkini manuahi o ke kila kila, no ka mea, pono nā hopena passivation a me nā hoʻonā flushing maʻalahi e hoʻolaha i nā huahana corrosion sulfide a pale i ka hoʻokumu ʻia ʻana o nā ʻeke waikawa.
Mai hoʻopau i nā ʻāpana kila kila carburized a nitrided paha. Hiki ke hoʻemi ʻia ke kūpaʻa ʻana o ka pala o nā ʻāpana i mālama ʻia ma kēia ʻano a hiki i ka wā e hōʻino ʻia ai i loko o ka ʻauʻau passivation.
Mai hoʻohana i nā mea hana metala hao i nā kūlana hale hana i maʻemaʻe ʻole. Hiki ke pale ʻia nā ʻāpana kila ma ka hoʻohana ʻana i nā mea hana carbide a i ʻole keramika.
E hoʻomaopopo he hiki ke pala i loko o ka ʻauʻau passivation inā ʻaʻole i mālama pono ʻia ka ʻāpana i ka wela. Pono e hoʻopaʻakikī ʻia nā papa Martensitic me ke kalapona kiʻekiʻe a me ka chromium no ke kūpaʻa ʻana i ka pala.
Hoʻopau pinepine ʻia ka passivation ma hope o ka hoʻomāinoino ʻana ma nā mahana e mālama ai i ke kūpaʻa ʻana i ka corrosion.
Mai hoʻowahāwahā i ka nui o ka waikawa nitric i loko o ka ʻauʻau passivation. Pono e hana i nā nānā manawa me ka hoʻohana ʻana i ke kaʻina hana titration maʻalahi i manaʻo ʻia e Carpenter. Mai passivate ma mua o hoʻokahi kila kila i ka manawa. Pale kēia i ka huikau pipiʻi a pale i nā hopena galvanic.
E pili ana i nā mea kākau: ʻO Terry A. DeBold he loea R&D no nā Stainless Steel Alloys a ʻo James W. Martin he loea Bar Metallurgy ma Carpenter Technology Corp.(Heluhelu, Penesilevania).
ʻEhia ke kumukūʻai? ʻEhia ka nui o ka wahi e pono ai iaʻu? He aha nā pilikia kaiapuni e kū nei iaʻu? Pehea ka piʻi o ke kaʻina aʻo? He aha ka anodizing? Aia ma lalo nā pane i nā nīnau mua a nā haku e pili ana i ka anodizing o loko.
ʻO ka loaʻa ʻana o nā hopena kūlike a kiʻekiʻe hoʻi mai ke kaʻina hana wili waena ʻole e pono ai kahi ʻike kumu. ʻO ka hapa nui o nā pilikia noi e pili ana i ka wili waena ʻole e kū mai ana mai ka nele o ka ʻike i nā kumu. Hōʻike kēia ʻatikala i ke kumu e hana ai ke kaʻina hana noʻonoʻo ʻole a pehea e hoʻohana pono ai iā ia i kāu hale hana.