Kanthal AF alloy 837 resistohm alchrome Y fecral alloy

Kanthal AF bụ ihe e ji ígwè ferritic-chromium-aluminium alloy (FeCrAl alloy) mee maka ojiji n'oge okpomọkụ ruru 1300°C (2370°F). A na-eji ihe e ji mee ihe a mara ya site na iguzogide oxidation dị mma na nkwụsi ike dị mma nke na-eme ka ihe dị ogologo ndụ.

A na-ejikarị Kan-thal AF eme ihe n'ihe ndị na-ekpo ọkụ eletrik n'ime ọkụ ụlọ ọrụ mmepụta ihe na ngwa ụlọ.

Ihe atụ nke ojiji n'ụlọ ọrụ ngwa bụ na ihe ndị e ji eme ihe maka igwe e ji eme achịcha, ihe ndị na-akpọ nkụ ntutu, ihe ndị e ji ihe dị ka meander mee maka ihe na-ekpo ọkụ fan na dị ka ihe ndị e ji eme ka eriri kpuchie ihe na-ekpo ọkụ n'elu iko seramiiki n'ọtụtụ ebe, na ihe na-ekpo ọkụ seramiiki maka efere esi mmiri, ihe na-ekpo ọkụ seramiiki e ji ihe na-esi nri mee maka efere esi nri nwere ihe na-ekpo ọkụ seramiiki, na ihe ndị na-ekpo ọkụ coil a kwụnyere maka ihe na-ekpo ọkụ fan, na ihe ndị na-ekpo ọkụ waya kwụ ọtọ maka radiators, ihe na-ekpo ọkụ convection, na ihe ndị na-ekpo ọkụ porcupine maka egbe ikuku ọkụ, radiators, ihe na-akpọ nkụ tumble.

Nchịkọta N'ọmụmụ ihe a, a kọwara usoro mmebi nke FeCrAl alloy azụmahịa (Kanthal AF) n'oge a na-ekpo ọkụ na gas nitrogen (4.6) na 900 °C na 1200 °C. E mere ule isothermal na thermo-cyclic nwere oge ngosipụta dị iche iche, ọnụego okpomọkụ, na okpomọkụ a na-ekpo ọkụ. E mere ule oxidation na ikuku na gas nitrogen site na nyocha thermogravimetric. A na-eji nyocha electron microscopy (SEM-EDX), Auger electron spectroscopy (AES), na nyocha ion focused (FIB-EDX) mara microstructure ahụ. Nsonaazụ ya na-egosi na ọganihu nke nchara na-eme site na ịmepụta mpaghara nitridation dị n'okpuru ala, nke mejupụtara ihe ndị mejupụtara AlN phase, nke na-ebelata ọrụ aluminum ma na-akpata embrittlement na spallation. Usoro nke nhazi Al-nitride na uto nke Al-oxide scale na-adabere na okpomọkụ annealing na ọnụego okpomọkụ. A chọpụtara na nitride nke FeCrAl alloy bụ usoro dị ngwa karịa oxidation n'oge a na-ekpochapụ gas nitrogen nwere obere nrụgide akụkụ oxygen ma na-anọchite anya isi ihe na-akpata mmebi alloy.

Okwu Mmalite: A maara alloys dabere na FeCrAl (Kanthal AF ®) nke ọma maka oke iguzogide oxidation ha na okpomọkụ dị elu. Ihe onwunwe a dị mma metụtara nhazi nke alumina kwụsiri ike na thermodynamically, nke na-echebe ihe ahụ pụọ ​​na oxidation ọzọ [1]. N'agbanyeghị ihe ndị na-eguzogide oxidation dị elu, enwere ike ịkpa oke ndụ nke ihe ndị e ji alloys dabere na FeCrAl mepụta ma ọ bụrụ na akụkụ ndị ahụ na-apụtakarị na okirikiri okpomọkụ na okpomọkụ dị elu [2]. Otu n'ime ihe kpatara nke a bụ na a na-eri ihe na-emepụta nha, aluminom, na matrix alloy na mpaghara ala n'ihi mgbawa thermo-shock ugboro ugboro na mgbanwe nke nha alumina. Ọ bụrụ na ọdịnaya aluminom fọdụrụ ebelata n'okpuru oke dị mkpa, alloy ahụ enweghịzi ike ịgbanwe nha nchebe ahụ, na-ebute oxidation dị egwu site na ịmepụta oxides dabere na ígwè na chromium na-eto ngwa ngwa [3,4]. Dabere na ikuku gbara ya gburugburu na permeability nke oxides elu nke a nwere ike ime ka oxidation ma ọ bụ nitridation dị n'ime ma ọ bụ nhazi nke usoro ndị na-adịghị mma na mpaghara ala n'okpuru [5]. Han na Young egosila na n'ọkwa alumina nke na-emepụta Ni Cr Al alloys, usoro mgbagwoju anya nke oxidation na nitridation dị n'ime na-etolite [6,7] n'oge ịgbagharị okpomọkụ na okpomọkụ dị elu n'ikuku ikuku, karịsịa na alloys nwere nitride formers siri ike dị ka Al na Ti [4]. A maara na chromium oxide scales dị ka nitrogen na-abanye, Cr2 N na-etolite ma dị ka oyi akwa obere ma ọ bụ dị ka ihe na-akpalite ime [8,9]. Enwere ike ịtụ anya na mmetụta a ga-adị njọ karịa n'okpuru ọnọdụ ịgbagharị okpomọkụ nke na-eduga na mgbawa oxide scale ma belata irè ya dị ka ihe mgbochi na nitrogen [6]. Ya mere, a na-achịkwa omume nchara site na asọmpi dị n'etiti oxidation, nke na-eduga na nhazi/ndozi alumina nchebe, na ntinye nitrogen na-eduga na nitridation dị n'ime nke alloy matrix site na ịmepụta AlN phase [6,10], nke na-eduga na spllation nke mpaghara ahụ n'ihi mmụba okpomọkụ dị elu nke AlN phase ma e jiri ya tụnyere alloy matrix [9]. Mgbe a na-ekpughe ihe ndị dị na FeCrAl n'ime oke okpomọkụ n'ime ikuku nwere oxygen ma ọ bụ ndị ọzọ na-enye oxygen dịka H2O ma ọ bụ CO2, oxidation bụ mmeghachi omume kachasị, na ụdị alumina scale, nke na-adịghị eguzogide oxygen ma ọ bụ nitrogen na okpomọkụ dị elu ma na-enye nchebe megide nbanye ha na matrix alloy. Mana, ọ bụrụ na ekpughere ya na ikuku mbelata (N2+H2), na mgbawa alumina scale nchebe, oxidation mpaghara na-amalite site na ịmepụta Cr na Ferich oxides na-adịghị echebe, nke na-enye ụzọ dị mma maka mgbasa nitrogen n'ime matrix ferritic na nhazi nke AlN phase [9]. A na-ejikarị ikuku nitrogen nchebe (4.6) eme ihe n'ọrụ mmepụta ihe nke FeCrAl alloys. Dịka ọmụmaatụ, ihe na-ekpo ọkụ na-eguzogide na ọkụ ọkụ na-agwọ okpomọkụ nwere ikuku nitrogen nchebe bụ ihe atụ nke ojiji zuru oke nke ihe ndị dị na FeCrAl alloys na gburugburu ebe dị otú ahụ. Ndị dere akwụkwọ na-akọ na ọnụego oxidation nke ihe ndị dị na FeCrAlL alloys na-adị nwayọ nke ukwuu mgbe a na-eme ka ha dị jụụ na ikuku nwere obere nrụgide akụkụ oxygen [11]. Ebumnuche nke ọmụmụ ihe a bụ ịchọpụta ma ọ bụrụ na itinye gas nitrogen (99.996%) (ọkwa ọcha Messer® O2 + H2O < 10 ppm) emetụta nguzogide nchara nke FeCrAl alloy (Kanthal AF) na oke ọ dabere na okpomọkụ annealing, mgbanwe ya (ịgbagharị okpomọkụ), na ọnụego okpomọkụ.