Tare da ci gaban masana'antu irin su ƙarfe da ƙarfe, masana'antar petrochemical, jiragen ruwa da wutar lantarki, tsarin welded yakan ci gaba a cikin manyan sikelin, manyan ƙarfi da ma'auni, wasu kuma har yanzu suna aiki cikin ƙarancin zafin jiki. cryogenic, kafofin watsa labarai masu lalata da sauran mahalli.
Sabili da haka, ana ƙara amfani da nau'i-nau'i daban-daban na ƙananan ƙarfe mai ƙarfi, matsakaici da matsakaicin ƙarfe, ƙarfe mai ƙarfi, da kayan haɗin gwal iri-iri. Duk da haka, tare da aikace-aikacen waɗannan ma'auni na karfe da kayan aiki, yawancin sababbin matsaloli suna haifar da samar da walda, daga cikin abin da ya fi dacewa kuma mai tsanani shine fashewar walda.
Karas wani lokaci yana bayyana yayin walda da kuma wani lokacin yayin sanyawa ko aiki, abin da ake kira tsage-tsage. Saboda ba za a iya gano irin waɗannan tsaga a masana'anta ba, irin waɗannan fasahohin sun fi haɗari. Akwai fasahohi iri-iri da yawa da aka haifar a cikin aikin walda. Bisa ga binciken na yanzu, bisa ga yanayin tsaga, ana iya raba su kusan zuwa kashi biyar masu zuwa:
1. Zafi mai zafi
Ana haifar da tsagewar zafi a yanayin zafi mai zafi yayin waldawa, don haka ana kiran su da zafi. Dangane da nau'in karfen da za a welded, siffar, yanayin zafi da kuma manyan dalilan da aka haifar da fashewar zafi kuma sun bambanta. Saboda haka, zafi mai zafi ya kasu kashi uku: crystallization cracks, liquefaction crack da polygonal fasa.
1. Crystal tsatsa
A cikin mataki na gaba na crystallization, fim din ruwa da aka kafa ta hanyar ƙananan ƙarar eutectic yana raunana haɗin tsakanin hatsi, kuma fasa yana faruwa a ƙarƙashin aikin damuwa.
Yafi faruwa a cikin welds na carbon karfe da low-alloy karfe tare da ƙarin ƙazanta (babban abun ciki na sulfur, phosphorus, baƙin ƙarfe, carbon, da silicon) da welds na guda-lokaci austenitic karfe, nickel tushen gami da wasu aluminum gami. tsakiya. A cikin ɗaiɗaikun lokuta, ƙwanƙwasa crystalline kuma na iya faruwa a yankin da zafi ya shafa.
2. Babban zafin jiki mai fashewa
A karkashin aikin mafi girman zafin jiki na sake zagayowar thermal na walda, remelting yana faruwa a tsakanin yankin da zafi ya shafa da yadudduka na walda mai yawa, kuma ana haifar da fasa a ƙarƙashin aikin danniya.
Yana faruwa ne a cikin manyan karafa masu ƙarfi da ke ɗauke da chromium da nickel, ƙarfe na austenitic, da wasu allunan tushen nickel a cikin yankin kabu na kusa ko tsakanin walda masu yawa. Lokacin da abun ciki na sulfur, phosphorus da silicon carbon a cikin tushe karfe da walda waya ya yi girma, da hali na liquefaction fatattaka za su karu sosai.
Lokacin aikawa: Afrilu-18-2022