Karfe mai bakin ƙarfe mai duplex ya kai kashi 80% na yawan amfani da ma'aunin duplex, super duplex da hyper duplex. An haɓaka su a shekarun 1930 don amfani a masana'antar takarda da ɓangaren litattafan almara, an gina ƙarfe mai duplex a kusa da abun da ke cikin 22% Cr da kuma gaurayen tsarin austenitic:ferritic wanda ke samar da kyawawan halaye na injiniya.
Idan aka kwatanta da ƙarfen austenitic na yau da kullun na 304/316, dangin ma'aunin duplex yawanci suna da ƙarfi sau biyu kuma suna ba da babban haɓakawa a cikin juriyar tsatsa. Ƙara yawan sinadarin chromium na ƙarfen bakin zai ƙara juriyar tsatsa ta rami. Duk da haka, Lambar Daidaitacciyar Juriya ta Pitting Resistance (PREN) wacce ke nuna juriyar ƙarfe ga tsatsa ta rami shi ma ya haɗa da wasu abubuwa da yawa a cikin dabararsa. Ana iya amfani da wannan dabarar don bayyana yadda bambancin da ke tsakanin UNS S31803 da UNS S32205 ya samo asali da kuma ko yana da mahimmanci.
Bayan haɓaka ƙarfe mai kauri biyu, an ɗauki bayanin farko na su a matsayin UNS S31803. Duk da haka, wasu manyan masana'antun suna ci gaba da samar da wannan matakin zuwa saman ƙayyadaddun da aka yarda. Wannan ya nuna sha'awarsu ta haɓaka aikin tsatsa na ƙarfe, tare da taimakon ci gaban tsarin yin ƙarfe na AOD wanda ya ba da damar ƙara yawan abubuwan da ke ciki. Bugu da ƙari, ya kuma ba da damar yin tasiri ga matakin ƙarin nitrogen, maimakon kawai gabatar da shi azaman ɓangaren baya. Saboda haka, matakin duplex mafi aiki ya nemi haɓaka matakan chromium (Cr), molybdenum (Mo) da nitrogen (N). Bambanci tsakanin ƙarfe mai kauri biyu wanda abun da ke ciki ya cika ƙasan ƙayyadaddun, idan aka kwatanta da wanda ya kai saman ƙayyadaddun zai iya zama maki da yawa bisa ga dabarar PREN = %Cr + 3.3 %Mo + 16 % N.
Domin a bambance ƙarfe mai siffar duplex da aka samar a saman kewayon kayan haɗin, an gabatar da ƙarin bayani, wato UNS S32205. Bakin ƙarfe mai siffar duplex da aka yi wa taken S32205 (F60) zai cika taken S31803 (F51), yayin da akasin haka ba gaskiya ba ne. Saboda haka, ana iya samun takardar shaidar S32205 a matsayin S31803.
| Matsayi | Ni | Cr | C | P | N | Mn | Si | Mo | S |
| S31803 | 4.5-6.5 | 21.0-23.0 | Matsakaicin 0.03 | Matsakaicin 0.03 | 0.08-0.20 | Matsakaicin 2.00 | Matsakaicin 1.00 | 2.5-3.5 | Matsakaicin 0.02 |
| S32205 | 4.5-6.5 | 22-23.0 | Matsakaicin 0.03 | Matsakaicin 0.03 | 0.14-0.20 | Matsakaicin 2.00 | Matsakaicin 1.00 | 3.0-3.5 | Matsakaicin 0.02 |
SAKYSTEEL tana da cikakken nau'in ƙarfe mai duplex a matsayin abokin tarayya na rarrabawa na Sandvik. Muna da S32205 a girma daga 5/8″ har zuwa 18″ a cikin sandar zagaye, tare da yawancin kayanmu suna cikin matakin Sanmac® 2205, wanda ke ƙara 'ingantaccen injina a matsayin misali' ga sauran kadarorin. Bugu da ƙari, muna kuma da nau'ikan sandar S32205 mai rami daga rumbun ajiyarmu na Burtaniya, da farantin har zuwa inci 3 daga rumbun ajiyarmu na Portland, Amurka.
Lokacin Saƙo: Oktoba-25-2019