Uqinisekisile ukuthi izingxenye zenziwe ngokwezidingo. Manje qiniseka ukuthi uthatha izinyathelo zokuvikela lezi zingxenye endaweni amakhasimende akho ayilindele. #base
Ukudlula kwe-passivation kusalokhu kuyisinyathelo esibalulekile ekukhuliseni ukumelana nokugqwala kwezingxenye kanye nezinhlangano ezenziwe ngensimbi engagqwali. Lokhu kungenza umehluko phakathi kokusebenza okwanelisayo kanye nokwehluleka kwangaphambi kwesikhathi. Ukudlula kwe-passivation okungalungile kungabangela ukugqwala.
I-Passivation iyindlela yokwenza izinto ngemva kokwenziwa ekhulisa ukumelana kokugqwala okungokwemvelo kwezinsimbi zensimbi engagqwali lapho kwenziwa khona umsebenzi. Lokhu akukhona ukususa noma ukupenda.
Akukho ukuvumelana ngendlela eqondile okusebenza ngayo i-passivation. Kodwa kwaziwa ngokuqinisekile ukuthi kukhona ifilimu ye-oxide evikelayo ebusweni bensimbi engagqwali engagqwali engagqwali. Le filimu engabonakali kuthiwa incane kakhulu, ingaphansi kuka-0.00000001 intshi ubukhulu, okucishe kube yi-1/100,000th ubukhulu bezinwele zomuntu!
Ingxenye yensimbi engagqwali ehlanzekile, esanda kufakwa, epholishiwe, noma efakwe uviniga izothola ngokuzenzakalelayo le filimu ye-oxide ngenxa yokuchayeka ku-oxygen yomoya-mpilo womkhathi. Ngaphansi kwezimo ezinhle, lolu ngqimba lwe-oxide oluvikelayo lumboza ngokuphelele zonke izindawo zengxenye.
Nokho, empeleni, ukungcola okufana nokungcola kwasefektri noma izinhlayiya zensimbi ezivela kumathuluzi okusika kungangena ebusweni bezingxenye zensimbi engagqwali ngesikhathi sokucubungula. Uma kungasuswa, lezi zidalwa zangaphandle zinganciphisa ukusebenza kahle kwefilimu yokuvikela yokuqala.
Ngesikhathi somshini wokusika, iminonjana yensimbi ekhululekile ingasuswa kuthuluzi bese idluliselwa ebusweni bomsebenzi wensimbi engagqwali. Kwezinye izimo, kungase kuvele ungqimba oluncane lokugqwala engxenyeni. Eqinisweni, lokhu kungukugqwala kwensimbi yamathuluzi, hhayi insimbi eyisisekelo. Ngezinye izikhathi imifantu evela ezinhlayiyeni zensimbi ezifakwe kumathuluzi okusika noma imikhiqizo yazo yokugqwala ingaguguza ingxenye ngokwayo.
Ngokufanayo, izinhlayiya ezincane zokungcola kwensimbi okune-ferrous zinganamathela ebusweni bengxenye. Nakuba insimbi ingase ibonakale ikhazimula esimweni sayo esiphelile, ngemva kokuchayeka emoyeni, izinhlayiya ezingabonakali zensimbi yamahhala zingabangela ukugqwala kobuso.
Ama-sulfide abonakalayo nawo angaba yinkinga. Enziwa ngokufaka isibabule ensimbini engagqwali ukuze kuthuthukiswe ukusebenza kahle komshini. Ama-sulfide andisa ikhono le-alloy lokwenza ama-chips ngesikhathi somshini wokusika, angasuswa ngokuphelele ethuluzini lokusika. Uma izingxenye zingasuswanga kahle, ama-sulfide angaba yindawo yokuqala yokugqwala kobuso bemikhiqizo yezimboni.
Kuzo zombili izimo, i-passivation iyadingeka ukuze kwandiswe ukumelana kokugqwala kwemvelo kwensimbi engagqwali. Isusa ukungcola okungaphezulu njengezinhlayiya zensimbi nezinhlayiya zensimbi kumathuluzi okusika angakha ukugqwala noma abe yindawo yokuqala yokugqwala. I-passivation isusa nama-sulfide atholakala ebusweni bezinsimbi zensimbi engagqwali ezisikiwe ezivulekile.
Inqubo enezinyathelo ezimbili inikeza ukumelana okuhle kakhulu nokugqwala: 1. Ukuhlanza, inqubo eyinhloko, kodwa ngezinye izikhathi ayinakwa 2. Ukugeza nge-asidi noma ukudlulisa umoya.
Ukuhlanza kufanele kube yinto eza kuqala ngaso sonke isikhathi. Izindawo kumele zihlanzwe kahle amafutha, i-coolant noma ezinye izinsalela ukuze kuqinisekiswe ukumelana nokugqwala okuhle kakhulu. Izinsalela zomshini noma ezinye izinsalela zasefektri zingasulwa kancane engxenyeni. Izihlanzi noma izihlanzi zezentengiselwano zingasetshenziswa ukususa amafutha noma izinsalela zokucubungula. Izinto zangaphandle ezifana nama-thermal oxides zingadinga ukususwa ngezindlela ezifana nokugaya noma ukukha amanzi.
Ngezinye izikhathi umqhubi womshini angase angawuhlanzisi umshini, ngephutha ekholelwa ukuthi ukuhlanza kanye nokungasebenzisi amandla kuzokwenzeka ngesikhathi esisodwa, ngokumane acwilise ingxenye enamafutha ebhavini eline-asidi. Ngeke kwenzeke. Ngokuphambene nalokho, amafutha angcolile asabela ne-asidi ukuze akhe amabhamuza omoya. Lawa mabhamuza aqoqana phezu kwendawo yokusebenza futhi aphazamise ukungasebenzisi amandla.
Okubi nakakhulu, ukungcoliswa kwezixazululo zokudlulisa ukukhanya, ngezinye izikhathi eziqukethe amazinga aphezulu ama-chloride, kungabangela "ukukhanya". Ngokungafani nokukhiqiza ifilimu ye-oxide efiselekayo enobuso obucwebezelayo, obuhlanzekile, obumelana nokugqwala, ukugqwala ukukhanya kungabangela ukugqwala okukhulu noma ukuba mnyama kobuso—ukuwohloka kobuso okwenza ukugqwala kuklanyelwe ukwenza ngcono.
Izingxenye zensimbi engagqwali ze-Martensitic [ezinobuthi, ezingamelana nokugqwala okulinganiselwe, zikhiqiza amandla afinyelela ku-280,000 psi (1930 MPa)] ziyacinywa emazingeni okushisa aphezulu bese ziqiniswa ukuze zinikeze ubulukhuni obufunwayo kanye nezakhiwo zemishini. Ama-alloy aqinisiwe anemvula (anamandla angcono kanye nokumelana nokugqwala kune-martensitic grades) angalungiswa ngesisombululo, afakwe umshini kancane, agcinwe emazingeni okushisa aphansi, bese eqedwa.
Kulesi simo, ingxenye kumele ihlanzwe kahle nge-degreaser noma i-cleaner ngaphambi kokwelashwa ngokushisa ukuze kususwe noma yimiphi iminonjana yoketshezi olusikiwe. Ngaphandle kwalokho, i-coolant esele engxenyeni ingabangela i-oxidation eningi. Lesi simo singabangela ukwakheka kwama-dents ezingxenyeni ezincane ngemva kokususwa nge-asidi noma izindlela zokuhudula. Uma i-coolant ishiywa ezingxenyeni ezicwebezelayo eziqinile, njengasesithandweni se-vacuum noma esimo esivikelayo, i-surface carburization ingenzeka, okuholela ekulahlekelweni kokumelana nokugqwala.
Ngemva kokuhlanza kahle, izingxenye zensimbi engagqwali zingacwiliswa ebhavini le-asidi engasebenzi. Noma iyiphi yalezi zindlela ezintathu ingasetshenziswa - ukungasebenzi nge-nitric acid, ukungasebenzi nge-nitric acid ene-sodium dichromate, kanye nokungasebenzi nge-citric acid. Indlela yokusebenzisa incike ebangeni lensimbi engagqwali kanye nenqubo yokwamukelwa echaziwe.
Amagreyidi e-chromium e-nickel amelana nokugqwala angasuswa kubhavu we-nitric acid ongu-20% (v/v) (Isithombe 1). Njengoba kuboniswe etafuleni, izinsimbi ezingagqwali ezingamelani kakhulu zingasuswa ngokufaka i-sodium dichromate ebhavuni le-nitric acid ukuze kwenziwe isisombululo sibe ne-oxidizing futhi sikwazi ukwakha ifilimu esusayo ebusweni bensimbi. Enye indlela yokufaka esikhundleni se-nitric acid nge-sodium chromate ukwandisa ukuhlushwa kwe-nitric acid ku-50% ngevolumu. Kokubili ukungezwa kwe-sodium dichromate kanye nokuhlushwa okuphezulu kwe-nitric acid kunciphisa amathuba okuba kube nokukhanya okungafunwa.
Inqubo yokudlulisa amandla ezinsimbi ezingagqwali ezisebenza ngomshini (eboniswe ku-Fig. 1) ihluke kancane enkambisweni yamazinga ensimbi engagqwali angasebenzi ngomshini. Lokhu kungenxa yokuthi ngesikhathi sokudlulisa amandla ebhavini le-nitric acid amanye noma wonke ama-sulfide aqukethe i-sulfur asebenza ngomshini ayasuswa, okudala ukungalingani okuncane ebusweni bento yokusebenza.
Ngisho nokugeza ngamanzi okuphumelelayo ngokuvamile kungashiya i-asidi esele kulezi ziphazamiso ngemva kokungasebenzi. Le-asidi izohlasela ubuso bengxenye uma ingasuswanga noma ingasuswa.
Ukuze kusetshenziswe insimbi engagqwali kalula emshinini, uCarpenter uthuthukise inqubo ye-AAA (Alkaline-Acid-Alkaline), eqeda i-asidi esele. Le ndlela yokusetshenziswa ingaqedwa ngaphansi kwamahora ama-2. Nansi inqubo yesinyathelo ngesinyathelo:
Ngemva kokususa amafutha, cwilisa izingxenye kusisombululo se-sodium hydroxide esingu-5% ku-160°F kuya ku-180°F (71°C kuya ku-82°C) imizuzu engama-30. Bese uhlanza izingxenye kahle emanzini. Bese ucwilisa ingxenye imizuzu engama-30 kusisombululo se-nitric acid esingu-20% (v/v) esiqukethe i-sodium dichromate engu-3 oz/gal (22 g/l) ku-120°F kuya ku-140°F (49°C) kuya ku-60°C. ) Ngemva kokususa ingxenye ebhavini, yihlanze ngamanzi, bese uyicwilisa kusisombululo se-sodium hydroxide imizuzu engama-30. Hlanza ingxenye futhi ngamanzi bese uyomisa, uqedele indlela ye-AAA.
Ukudlula kwe-citric acid kuya ngokuya kuthandwa ngabakhiqizi abafuna ukugwema ukusetshenziswa kwama-mineral acid noma izixazululo eziqukethe i-sodium dichromate, kanye nezinkinga zokulahla kanye nokukhathazeka okukhulu kokuphepha okuhlobene nokusetshenziswa kwazo. I-citric acid ibhekwa njengenobungani nemvelo ngazo zonke izindlela.
Nakuba ukususwa kwe-citric acid kunikeza izinzuzo zemvelo ezikhangayo, izitolo eziye zaphumelela ngokususwa kwe-inorganic acid futhi ezingenazo izinkinga zokuphepha zingase zifune ukuqhubeka. Uma laba basebenzisi benesitolo esihlanzekile, imishini isesimweni esihle futhi ihlanzekile, i-coolant ayinazo izinsalela ze-ferrous zasefektri, futhi inqubo iveza imiphumela emihle, kungase kungabi nesidingo sangempela sokushintsha.
Ukudlula kwe-citric acid bath kutholakale kuwusizo ezinhlobonhlobo zezinsimbi ezingagqwali, kufaka phakathi amazinga amaningana ensimbi engagqwali, njengoba kuboniswe kuMfanekiso 2. Ukuze kube lula, uMfanekiso 2. 1 uhlanganisa indlela yendabuko yokudlula nge-nitric acid. Qaphela ukuthi amafomula amadala e-nitric acid achazwa njengamaphesenti ngevolumu, kuyilapho amazinga amasha e-citric acid echazwa njengamaphesenti ngesisindo. Kubalulekile ukuqaphela ukuthi lapho kwenziwa lezi zinqubo, ibhalansi ecophelelayo yesikhathi sokucwilisa, izinga lokushisa lokugeza, kanye nokuhlushwa kubalulekile ukuze kugwenywe "ukukhanya" okuchazwe ngenhla.
Ukudlula kuyahlukahluka kuye ngokuqukethwe kwe-chromium kanye nezici zokucubungula zohlobo ngalunye. Qaphela amakholomu eNqubo 1 noma iNqubo 2. Njengoba kuboniswe kuMfanekiso 3, iNqubo 1 inezinyathelo ezimbalwa kuneNqubo 2.
Ukuhlolwa kwelebhu kukhombisile ukuthi inqubo yokudlulisa i-citric acid ithambekele kakhulu “ekubileni” kunenqubo ye-nitric acid. Izici ezibangela lokhu kuhlasela zifaka phakathi izinga lokushisa eliphezulu kakhulu lokugeza, isikhathi eside kakhulu sokucwilisa, kanye nokungcola kokugeza. Imikhiqizo esekelwe ku-citric acid equkethe izithibi zokugqwala nezinye izithasiselo ezifana nezinto zokumanzisa iyatholakala kwezentengiselwano futhi kubikwa ukuthi inciphisa ukuthambekela “kokugqwala kwe-flash”.
Ukukhetha kokugcina kwendlela yokudlulisa idatha kuzoncika ezindinganisweni zokwamukelwa ezibekwe yikhasimende. Bheka i-ASTM A967 ukuthola imininingwane. Ingatholakala ku-www.astm.org.
Ukuhlolwa kuvame ukwenziwa ukuhlola ubuso bezingxenye ezingasebenzi. Umbuzo okufanele uphendulwe uthi “Ingabe ukungasebenzi kususa insimbi ekhululekile futhi kwenze ngcono ukumelana nokugqwala kwama-alloy ukuze kusikwe ngokuzenzakalelayo?”
Kubalulekile ukuthi indlela yokuhlola ifane nekilasi elihlolwayo. Ukuhlolwa okuqinile kakhulu ngeke kuphumelele izinto ezinhle kakhulu, kanti ukuhlolwa okubuthakathaka kakhulu kuzodlula izingxenye ezingagculisi.
I-PH kanye nezinsimbi ezingagqwali ezingama-400 ezisebenza kalula zihlolwa kangcono ekamelweni elikwazi ukugcina umswakama ongu-100% (isampula imanzi) amahora angama-24 ku-95°F (35°C). Ingxenye evundlile ivame ukuba yindawo ebaluleke kakhulu, ikakhulukazi kuma-grade okusika akhululekile. Esinye isizathu salokhu ukuthi i-sulphide idonswa ohlangothini lomshini kulo lonke lolu daba.
Izindawo ezibucayi kufanele zibekwe phezulu, kodwa nge-engeli yama-degrees angu-15 kuya kwangu-20 ukusuka phezulu, ukuze kuvunyelwe ukulahleka komswakama. Izinto ezifakwe kahle ngeke zigqwale, yize kungase kuvele amabala amancane kuzo.
Amazinga ensimbi engagqwali e-Austenitic angahlolwa futhi ngokuhlolwa komswakama. Kulolu vivinyo, amaconsi amanzi kufanele abe khona ebusweni besampula, okubonisa insimbi yamahhala ngokuba khona kwanoma yikuphi ukugqwala.
Izinqubo zokudlulisa amandla ezinsimbi ezingagqwali ezisetshenziswa ngokuzenzakalelayo kanye nezinsimbi ezisetshenziswa ngesandla ezixazululweni ze-citric noma ze-nitric acid zidinga izinqubo ezahlukene. Ku-Fig. 3 ngezansi sinikeza imininingwane ngokukhethwa kwenqubo.
(a) Lungisa i-pH nge-sodium hydroxide. (b) Bheka umfanekiso 3(c) I-Na2Cr2O7 iyi-3 oz/gal (22 g/L) sodium dichromate ku-20% nitric acid. Enye indlela yale ngxube yi-50% nitric acid ngaphandle kwe-sodium dichromate.
Indlela esheshayo ukusebenzisa i-ASTM A380, Umkhuba Ojwayelekile Wokuhlanza, Ukususa Izikali, Nokudlulisa Izingxenye Zensimbi Engagqwali, Imishini, Nezinhlelo. Ukuhlolwa kufaka phakathi ukusula ingxenye ngesisombululo se-copper sulfate/sulfuric acid, ukuyigcina imanzi imizuzu eyi-6, nokubuka i-copper plating. Ngaphandle kwalokho, ingxenye ingacwiliswa esixazululweni imizuzu eyi-6. Uma insimbi incibilika, kwenzeka i-copper plating. Lokhu kuhlolwa akusebenzi ezindaweni zezingxenye zokucubungula ukudla. Futhi, akufanele kusetshenziswe ezinsimbini ze-martensitic ezingu-400 zochungechunge noma ezinsimbini ze-ferritic eziphansi ze-chromium njengoba kungase kube nemiphumela emibi engamanga.
Ngokomlando, ukuhlolwa kokufuthwa kukasawoti okungu-5% ku-95°F (35°C) kuye kwasetshenziswa futhi ukuhlola amasampula angavuthwanga. Lokhu kuhlolwa kuqinile kakhulu kwezinye izinhlobo futhi ngokuvamile akudingeki ukuqinisekisa ukusebenza kahle kokuvuthwa.
Gwema ukusebenzisa ama-chloride amaningi, angabangela ukuqubuka okuyingozi. Sebenzisa amanzi asezingeni eliphezulu kuphela ane-chloride engaphansi kwezingxenye ezingu-50 ngesigidi (ppm) noma nini lapho kungenzeka. Amanzi ompompi ngokuvamile anele, futhi kwezinye izimo angamelana nezingxenye ezingamakhulu amaningana ngesigidi sama-chloride.
Kubalulekile ukushintsha indawo yokugeza njalo ukuze ungalahlekelwa amandla okudlula, okungaholela ekushayweni kombani kanye nomonakalo ezingxenyeni. Indawo yokugeza kumele igcinwe ekushiseni okufanele, njengoba amazinga okushisa angalawulwa angabangela ukugqwala kwendawo.
Kubalulekile ukulandela isimiso sokushintsha isixazululo esithile ngesikhathi sokukhiqiza okukhulu ukuze kuncishiswe amathuba okungcoliswa. Isampula yokulawula yasetshenziswa ukuhlola ukusebenza kahle kwebhavu. Uma isampula ihlaselwe, sekuyisikhathi sokushintsha ibhavu.
Sicela uqaphele ukuthi eminye imishini ikhiqiza insimbi engagqwali kuphela; sebenzisa i-coolant efanayo ethandwayo yokusika insimbi engagqwali ngaphandle kwazo zonke ezinye izinsimbi.
Izingxenye ze-DO rack ziklanywa ngomshini ngokwehlukana ukuze kugwenywe ukuthintana kwensimbi nensimbi. Lokhu kubaluleke kakhulu ekucubunguleni insimbi engagqwali ngokukhululeka, njengoba izixazululo zokudlulisa amanzi kalula kanye nokuhlanza ziyadingeka ukuze kusabalale imikhiqizo yokugqwala kwe-sulfide futhi kuvinjelwe ukwakheka kwama-acid pockets.
Ungazisebenzisi izingxenye zensimbi engagqwali ezifakwe i-carburing noma i-nitride. Ukumelana nokugqwala kwezingxenye eziphathwe ngale ndlela kungancishiswa kuze kube yilapho zingalimala ebhavini lokugqwala.
Ungasebenzisi amathuluzi ensimbi anensimbi ezindaweni zokusebenzela ezingahlanzekile kangako. Ama-chip ensimbi angagwenywa ngokusebenzisa amathuluzi e-carbide noma e-ceramic.
Qaphela ukuthi ukugqwala kungenzeka ebhavini lokuhamba uma ingxenye ingalungiswanga kahle ngokushisa. Amazinga e-Martensitic anokuqukethwe okuphezulu kwekhabhoni ne-chromium kumele aqiniswe ukuze amelane nokugqwala.
Ukudlula ngokuvamile kwenziwa ngemva kokushisa okulandelayo emazingeni okushisa agcina ukumelana nokugqwala.
Ungakunaki ukugcwala kwe-nitric acid ebhavini lokungenisa umoya. Ukuhlolwa ngezikhathi ezithile kufanele kwenziwe kusetshenziswa inqubo elula ye-titration ephakanyiswe nguCarpenter. Ungasebenzisi insimbi engagqwali engaphezu kweyodwa ngesikhathi. Lokhu kuvimbela ukudideka okubizayo futhi kuvimbela ukusabela kwe-galvanic.
Mayelana Nababhali: UTerry A. DeBold unguchwepheshe we-R&D we-Stainless Steel Alloys kanti uJames W. Martin unguchwepheshe we-Bar Metallurgy kwaCarpenter Technology Corp.(Ukufunda, ePennsylvania).
Malini? Ngidinga isikhala esingakanani? Yiziphi izinkinga zemvelo engizobhekana nazo? Indlela yokufunda iphakeme kangakanani? Kuyini ngempela i-anodizing? Ngezansi kunezimpendulo zemibuzo yokuqala yabaphathi mayelana ne-anodizing yangaphakathi.
Ukuthola imiphumela ehambisanayo nesezingeni eliphezulu evela enkambisweni yokugaya engenasikhungo kudinga ukuqonda okuyisisekelo. Izinkinga eziningi zokusebenzisa ezihambisana nokugaya okungenasikhungo zivela ekungaqondini izisekelo. Lesi sihloko sichaza ukuthi kungani inqubo engenangqondo isebenza nokuthi ungayisebenzisa kanjani ngempumelelo eshabhu lakho.