Tambaya: Kwanan nan mun fara yin wasu ayyuka da ke buƙatar wasu abubuwan da za a yi da farko daga karfe 304 na bakin karfe, wanda aka yi masa walda da kansa da kuma ƙarfe mai laushi.Mun fuskanci wasu batutuwa tare da fasa walda tsakanin bakin karfe da bakin karfe har zuwa 1.25 inci kauri.An ambaci cewa muna da ƙananan matakan ferrite.Za a iya bayyana abin da yake da kuma yadda za a gyara shi?
A: Wannan tambaya ce mai kyau.Ee, za mu iya taimaka muku fahimtar abin da ƙananan ferrite ke nufi da yadda ake hana shi.
Da farko, bari mu dubi ma'anar bakin karfe (SS) da yadda ferrite ke da alaƙa da haɗin gwiwar welded.Black karfe da gami sun ƙunshi fiye da 50% baƙin ƙarfe.Wannan ya haɗa da duk carbon da bakin karfe, da kuma wasu wasu ƙungiyoyi.Aluminum, jan karfe, da titanium ba su ƙunshi baƙin ƙarfe ba, don haka suna da kyakkyawan misalan abubuwan da ba na ƙarfe ba.
Babban abubuwan da ke cikin wannan gami sune carbon karfe mai abun ciki na baƙin ƙarfe aƙalla 90% da bakin karfe mai baƙin ƙarfe na 70 zuwa 80%.Don a keɓance shi azaman SS, dole ne a ƙara aƙalla 11.5% chromium.Matakan chromium da ke sama da wannan ƙaramin bakin kofa suna haɓaka samuwar fim ɗin chromium oxide akan saman ƙarfe da kuma hana samuwar iskar shaka kamar tsatsa (iron oxide) ko lalata harin sinadarai.
Bakin karfe ya kasu kashi uku: austenitic, ferritic da martensitic.Sunan su ya fito ne daga tsarin crystal a dakin da zafin jiki wanda aka haɗa su.Wani rukuni na kowa shine duplex bakin karfe, wanda shine ma'auni tsakanin ferrite da austenite a cikin tsarin crystal.
Makin Austenitic, jerin 300, sun ƙunshi 16% zuwa 30% chromium da 8% zuwa 40% nickel, suna samar da tsarin lu'ulu'u na austenitic.Ana ƙara masu ƙarfafawa kamar nickel, carbon, manganese, da nitrogen yayin aikin yin ƙarfe don taimakawa samar da rabon austenite-ferrite.Wasu maki na gama gari sune 304, 316 da 347. Yana ba da juriya mai kyau na lalata;galibi ana amfani da su a cikin abinci, sinadarai, magunguna da masana'antu na cryogenic.Gudanar da samuwar ferrite yana ba da kyakkyawan ƙarfi a ƙananan yanayin zafi.
Ferritic SS shine nau'i nau'i nau'i 400 wanda yake da cikakkiyar maganadisu, ya ƙunshi 11.5% zuwa 30% chromium, kuma yana da tsarin kristal mai yawan gaske.Don haɓaka samuwar ferrite, masu ƙarfafawa sun haɗa da chromium, silicon, molybdenum da niobium yayin samar da ƙarfe.Irin waɗannan nau'ikan SS ana amfani da su sosai a cikin tsarin shaye-shaye na kera motoci da wutar lantarki kuma suna da ƙayyadaddun aikace-aikacen zafin jiki.Nau'o'in da aka saba amfani da su: 405, 409, 430 da 446.
Martensitic maki, wanda kuma ake magana a kai a matsayin jerin 400, kamar 403, 410, da 440, magnetic ne, sun ƙunshi 11.5% zuwa 18% chromium, kuma suna da tsarin crystal na martensitic.Wannan haɗin yana da mafi ƙarancin abun ciki na zinariya, yana sa su zama mafi ƙarancin tsada don samarwa.Suna ba da wasu juriya na lalata, ƙarfin ƙarfi, kuma ana amfani da su a cikin kayan tebur, kayan haƙori da na tiyata, kayan dafa abinci, da wasu nau'ikan kayan aikin.
Lokacin da kuka yi walda bakin karfe, nau'in juzu'i da aikace-aikacen sa a cikin sabis za su ƙayyade ƙarfen da ya dace da za a yi amfani da shi.Idan kuna amfani da tsarin garkuwar gas, kuna iya buƙatar kulawa ta musamman ga garkuwar gaurayawan gas don hana wasu matsalolin da ke da alaƙa da walda.
Don siyar da 304 zuwa kanta, kuna buƙatar lantarki E308/308L."L" yana nufin ƙananan carbon, wanda ke taimakawa hana lalata intergranular.Abubuwan da ke cikin carbon na waɗannan wayoyin ba su da ƙasa da 0.03%, idan wannan ƙimar ta wuce, haɗarin haɗarin carbon a iyakokin hatsi da haɗin gwiwar chromium don samar da chromium carbides yana ƙaruwa, wanda ya rage girman juriya na ƙarfe.Wannan yana bayyana idan lalata ta faru a yankin da zafi ya shafa (HAZ) na welds na bakin karfe.Wani abin la'akari don matakin L bakin karfe shine cewa suna da ƙananan ƙarfin ƙarfi a yanayin zafi mai tsayi fiye da madaidaiciyar maki bakin karfe.
Tun da 304 nau'in nau'in bakin karfe ne na austenitic, karfen weld daidai zai ƙunshi yawancin austenite.Duk da haka, wutar lantarki da kanta za ta ƙunshi na'urar ferrite, kamar molybdenum, don haɓaka samuwar ferrite a cikin ƙarfe na walda.Masu sana'a yawanci suna lissafin kewayon na yau da kullun don adadin ferrite don ƙarfe weld.Kamar yadda aka ambata a baya, carbon yana da ƙarfi austenitic stabilizer kuma saboda waɗannan dalilai yana da mahimmanci don hana ƙari ga ƙarfe na weld.
Lambobin Ferrite an samo su ne daga ginshiƙi na Scheffler da ginshiƙi WRC-1992, waɗanda ke amfani da dabarar nickel da chromium daidai gwargwado don ƙididdige ƙimar da lokacin da aka ƙirƙira akan ginshiƙi yana ba da lambar daidaitacce.Lamba ferrite tsakanin 0 da 7 yayi daidai da ƙarar kaso na tsarin crystal na ferritic da ke cikin ƙarfen weld, duk da haka, a mafi girman kashi, lambar ferrite tana ƙaruwa da sauri.Ka tuna cewa ferrite a cikin SS baya ɗaya da carbon karfe ferrite, amma wani lokaci da ake kira delta ferrite.Austenitic bakin karfe baya jure canje-canjen lokaci mai alaƙa da matakan zafin jiki mai girma kamar maganin zafi.
Samuwar Ferrite yana da kyawawa saboda ya fi ductile fiye da austenite, amma dole ne a sarrafa shi.Ƙananan abun ciki na ferrite na iya samar da walda tare da kyakkyawan juriya na lalata a wasu aikace-aikace, amma suna da matukar damuwa ga fashewar zafi yayin walda.Don amfanin gabaɗaya, adadin jiragen ruwa ya kamata ya kasance tsakanin 5 zuwa 10, amma wasu aikace-aikacen na iya buƙatar ƙima kaɗan ko mafi girma.Ana iya bincika ferrite cikin sauƙi a wurin aiki tare da alamar ferrite.
Tun da ka ambaci cewa kana da matsaloli tare da fatattaka da ƙananan ferrites, ya kamata ka yi dubi a kusa da filler karfe kuma tabbatar da cewa yana samar da isassun ferrites - a kusa da 8 ya kamata a yi abin zamba.Hakanan, idan kuna amfani da walƙiya-cored arc waldi (FCAW), waɗannan karafa na filler yawanci suna amfani da iskar garkuwa na 100% carbon dioxide ko cakuda 75% argon da 25% CO2, wanda zai iya sa ƙarfen walda ya sha carbon.Kuna iya canzawa zuwa tsarin waldawar baka na ƙarfe (GMAW) kuma kuyi amfani da 98% argon / 2% cakuda oxygen don rage yuwuwar ajiyar carbon.
Lokacin walda bakin karfe zuwa carbon karfe, dole ne a yi amfani da kayan filler E309L.Ana amfani da wannan ƙarfe na filler musamman don waldar ƙarfe mai kama da haka, yana samar da wani adadin ferrite bayan an narkar da ƙarfen carbon a cikin walda.Saboda karfen carbon yana ɗaukar wasu carbon, ana ƙara ferrite stabilizers zuwa ƙarfe mai filler don magance yanayin carbon don samar da austenite.Wannan zai taimaka hana zafin zafi lokacin walda.
A ƙarshe, idan kuna son gyara fashe masu zafi a cikin walƙiya bakin ƙarfe na austenitic, bincika isassun ƙarfe na ferrite kuma ku bi kyakkyawan aikin walda.Ci gaba da shigar da zafi ƙasa da 50 kJ/in, kula da matsakaicin matsakaicin zuwa ƙananan yanayin tsaka-tsaki, kuma tabbatar da haɗin gwiwar solder suna da tsabta kafin siyarwa.Yi amfani da ma'aunin da ya dace don bincika adadin ferrite akan weld, yana nufin 5-10.
WELDER, wanda a da ake kira Practical Welding Today, yana wakiltar ainihin mutanen da ke yin samfuran da muke amfani da su kuma suke aiki da su kowace rana.Wannan mujallar ta yi hidima ga al’ummar walda a Arewacin Amirka sama da shekaru 20.
Yanzu tare da cikakken damar yin amfani da bugu na dijital na FABRICATOR, samun sauƙin samun albarkatun masana'antu masu mahimmanci.
Buga na dijital na The Tube & Pipe Journal yanzu yana da cikakkiyar dama, yana ba da sauƙi ga albarkatun masana'antu masu mahimmanci.
Samun cikakken damar dijital zuwa Jaridar STAMPING, mai nuna sabbin fasahohi, mafi kyawun ayyuka da labaran masana'antu don kasuwar tallan ƙarfe.
Yanzu tare da cikakken damar dijital zuwa The Fabricator en Español, kuna da sauƙin samun dama ga albarkatun masana'antu masu mahimmanci.