Ƙunƙarar sanyi (ko ƙarancin zafin jiki) nasanyi birgima bututuyayin amfani ana wakilta ta tauri brittleness canjin zafin jiki Tc.Tc na ƙarfe mai tsabta (0.01% C) yana a -100C, kuma ƙasa da wannan zafin jiki, gaba ɗaya yana cikin yanayi mara ƙarfi.Yawancin gami abubuwa a cikin sanyi-birgima daidaici haske karfe bututu ƙara tauri brittleness mika mulki zafin jiki na sanyi-birgima madaidaicin haske karfe bututu, kara hali ga sanyi brittleness.Lokacin da ductile fracture ya auku a sama da dakin zafin jiki, da karaya saman sanyi-bidi birgima madaidaicin haske karfe bututu ne dimple siffa karaya, yayin da lokacin da gaggautsa karaya faruwa a low zafin jiki, shi ne cleavage karaya.
Dalilin ƙananan zafin jiki na sanyi birgima mai haske shine:
(1) Lokacin da ɓarna da tushen ɓarna a lokacin lalacewa ke toshe shi ta hanyar cikas (kamar iyakokin hatsi ko daidaitattun na biyu), damuwa na gida ya wuce ƙarfin ka'idar sanyi-birgima daidaitaccen bututun ƙarfe mai haske, wanda ke haifar da microcracks.
(2) Matsalolin da aka tattara da yawa suna haifar da microcrack a iyakar hatsi.
(3) Amsa a mahadar maƙallan zamewa biyu, yana haifar da ɓarna mara motsi% 26lt;010% 26gt, tare da microcrack mai siffa mai siffa wanda zai iya fashe tare da tsagewar jirgin.
Abubuwan da ke damun sanyin bushewar bututu masu haske sun haɗa da:
(1) Abubuwan ƙarfafa bayani masu ƙarfi.Phosphorus yana ƙara ƙarfin jujjuyawar zafin jiki mai ƙarfi;Akwai kuma molybdenum, titanium, da vanadium;Lokacin da abun ciki ya yi ƙasa, tasirin ba shi da mahimmanci, yayin da abun ciki ya yi girma, abubuwan da ke ƙara yawan zafin jiki mai ƙarfi sun haɗa da silicon, chromium, da jan karfe.Abubuwan da ke rage zafin jujjuyawar tauri sun haɗa da nickel, kuma abubuwan da ke raguwa da farko sannan kuma su ƙara ƙarfin jujjuya zafin canjin yanayi sun haɗa da manganese.
(2) Abubuwan da suka samar da kashi na biyu.Mafi mahimmancin kashi don haɓaka ƙarancin sanyi na sanyi-birgima daidaitaccen bututun ƙarfe mai haske tare da lokaci na biyu shine carbon.Kamar yadda abun cikin carbon a cikin sanyi-birgima madaidaicin bututun ƙarfe mai haske yana ƙaruwa, abun cikin pearlite a cikin bututun ƙarfe mai haske mai haske mai sanyi yana ƙaruwa.A matsakaita, ga kowane 1% karuwa a cikin pearlite girma, da tauri brittleness canjin zafin jiki yana ƙaruwa da 2.2 ℃ a matsakaita.
(3) Tasirin abun ciki na carbon akan raguwa a cikin karfen pearlite na ferritic.Bugu da kari na microalloying abubuwa kamar titanium, niobium, da vanadium siffofin tarwatsa nitrides ko carbonitrides, haifar da wani karuwa a cikin tauri brittleness canjin zafin jiki na sanyi-birgima madaidaicin haske karfe bututu.
(4) Girman hatsi yana rinjayar zafin canjin yanayin tauri, kuma yayin da hatsin ya yi girma, zafin canjin ƙarfin ƙarfi yana ƙaruwa.Tace girman hatsi yana rage halayen sanyin sanyi a cikin bututun ƙarfe mai haske da aka yi birgima, wanda hanya ce ta ko'ina.
Lokacin aikawa: Satumba-01-2023