Kanthal AF alloy 837 resistohm alchrome Y fecral gami

Kanthal AF shine ƙarfe-chromium-aluminium alloy (FeCrAl alloy) don amfani a yanayin zafi har zuwa 1300°C (2370°F). A gami yana da kyau kwarai juriya da iskar shaka da kwanciyar hankali mai kyau wanda ke haifar da tsawon rayuwa.

Kan-thal AF yawanci ana amfani dashi a cikin abubuwan dumama wutar lantarki a cikin tanderun masana'antu da na'urorin gida.

Misalin aikace-aikace a cikin masana'antar kayan aiki suna cikin abubuwan buɗaɗɗen mica don toasters, masu busar gashi, a cikin abubuwa masu siffa don masu dumama fan kuma azaman buɗe abubuwan coil akan fiber insulating abu a cikin manyan dumama gilashin yumbu a cikin jeri, a cikin yumbu dumama don faranti, coils. akan fiber na yumbu da aka ƙera don faranti tare da hobs na yumbu, a cikin abubuwan da aka dakatar da coil don masu dumama fan, a cikin abubuwan da aka dakatar da su madaidaiciyar wayoyi don radiators, masu dumama dumama, cikin abubuwan naman alade don bindigogin iska mai zafi, radiators, na'urar bushewa.

Abstract A cikin binciken da aka gabatar, an bayyana tsarin lalata na FeCrAl alloy na kasuwanci (Kanthal AF) yayin da ake toshe iskar nitrogen (4.6) a 900 ° C da 1200 ° C. Gwaje-gwajen isothermal da thermo-cyclic tare da bambance-bambancen lokutan bayyanarwa, ƙimar dumama, da yanayin zafi an yi. An yi gwajin iskar oxygen a cikin iska da iskar nitrogen ta hanyar nazarin thermogravimetric. Microstructure yana siffanta shi ta hanyar duba microscopy na lantarki (SEM-EDX), Auger electron spectroscopy (AES), da kuma nazarin ion beam (FIB-EDX). Sakamakon ya nuna cewa ci gaba da lalata yana faruwa ta hanyar samar da yankuna na nitridation na karkashin kasa, wanda ya ƙunshi nau'o'in nau'i na AlN, wanda ya rage aikin aluminum kuma yana haifar da haɓakawa da haɓakawa. Hanyoyin samuwar Al-nitride da haɓaka sikelin Al-oxide sun dogara ne akan rage zafin jiki da yawan dumama. An gano cewa nitridation na FeCrAl alloy ne mai sauri tsari fiye da hadawan abu da iskar shaka a lokacin annealing a cikin wani nitrogen gas tare da low oxygen parter matsa lamba da kuma wakiltar babban dalilin alloy lalacewa.

Gabatarwa FeCrAl - tushen gami (Kanthal AF ®) sananne ne don juriya na iskar shaka a yanayin zafi mai tsayi. Wannan kyakkyawan kayan yana da alaƙa da samuwar ma'aunin alumina mai ƙarfi na thermodynamically akan saman, wanda ke kare kayan daga ƙarin iskar shaka [1]. Duk da mafi girman kaddarorin juriya na lalata, rayuwar abubuwan abubuwan da aka ƙera daga FeCrAl - abubuwan gami za a iya iyakance su idan sassan ana yawan fallasa su zuwa hawan keken zafi a yanayin zafi [2]. Ɗaya daga cikin dalilan da ke haifar da haka shi ne cewa sikelin da ke samar da sikelin, aluminum, yana cinyewa a cikin matrix na alloy a cikin yankin ƙasa saboda maimaitawar thermo-shock da kuma gyara ma'aunin alumina. Idan sauran abun ciki na aluminium ya ragu a ƙarƙashin mahimmancin maida hankali, gami ba zai iya sake gyara ma'aunin kariya ba, yana haifar da bala'i mai fashewa ta hanyar samuwar tushen ƙarfe da sauri da oxides na tushen chromium [3,4]. Dangane da yanayin da ke kewaye da kuma iyawar oxides na saman wannan na iya sauƙaƙe ƙarin iskar oxygenation na ciki ko nitridation da samuwar matakan da ba a so a cikin yankin ƙasa [5]. Han da Young sun nuna cewa a cikin sikelin alumina da ke samar da Ni Cr Al alloys, wani hadadden tsari na oxidation na ciki da nitridation yana tasowa [6,7] yayin hawan keke na thermal a yanayin zafi mai tsayi a cikin yanayin iska, musamman ma a cikin allunan da ke dauke da tsoffin nitride kamar Al. da Ti [4]. An san ma'auni na Chromium oxide don zama mai jujjuyawar nitrogen, kuma Cr2 N yana yin ko dai azaman sikelin sikelin ko azaman hazo na ciki [8,9]. Ana iya sa ran wannan tasirin zai fi tsanani a ƙarƙashin yanayin hawan keke na zafi wanda ke haifar da fashewar sikelin oxide da rage tasirinsa a matsayin shinge ga nitrogen [6]. Don haka ana gudanar da halayen lalata ta hanyar gasa tsakanin iskar shaka, wanda ke haifar da samuwar alumina mai kariya / kiyayewa, da haɓakar nitrogen wanda ke haifar da nitridation na ciki na matrix alloy ta hanyar samuwar lokaci na AlN [6,10], wanda ke haifar da haɓakar haɓakar ƙwayoyin cuta. yankin saboda haɓakar yanayin zafi na AlN idan aka kwatanta da matrix alloy [9]. Lokacin fallasa FeCrAl gami ga yanayin zafi mai zafi a cikin yanayi tare da iskar oxygen ko wasu masu ba da iskar oxygen kamar H2O ko CO2, iskar shaka shine mafi girman halayen, da sikelin alumina, wanda ba shi da iskar oxygen ko nitrogen a yanayin zafi mai girma kuma yana ba da kariya daga kutsawa cikin su. alloy matrix. Amma, idan an fallasa shi ga raguwar yanayi (N2 + H2), da kuma fashewar sikelin alumina mai kariya, iskar oxygen ta gida tana farawa ta hanyar samuwar Cr da Ferich oxides marasa kariya, waɗanda ke ba da kyakkyawar hanya don yaduwar nitrogen a cikin matrix na ferritic da samuwar. na AlN Phase [9]. Ana yawan amfani da yanayin kariyar nitrogen (4.6) a cikin aikace-aikacen masana'antu na FeCrAl gami. Misali, masu dumama juriya a cikin tanderun jiyya mai zafi tare da yanayi mai karewa na nitrogen misali ne na aikace-aikacen gami da FeCrAl a cikin irin wannan yanayi. Marubutan sun ba da rahoton cewa adadin iskar oxygen na FeCrAlY alloys yana da hankali sosai yayin da yake raguwa a cikin yanayi tare da ƙarancin ƙarancin iskar oxygen [11]. Makasudin binciken shine don sanin ko annealing a (99.996%) nitrogen (4.6) gas (Messer® ƙayyadaddun ƙazanta matakin O2 + H2O <10 ppm) yana shafar juriya na lalata FeCrAl alloy (Kanthal AF) kuma zuwa menene ya dogara. a kan zafin jiki na annealing, da bambancinsa (thermal-cycling), da dumama farashin.