Izinguquko ku-microstructure kanye nezakhiwo ze-forgings ngesikhathi sokushisa

Forgingsngemva kokucisha, i-martensite kanye ne-austenite egciniwe ayizinzile, banokushintshashintsha kwenhlangano okuzenzakalelayo ekuzinzeni, njengekhabhoni ye-supersaturated e-martensite ukuze kuncishiswe ukubola kwe-austenite eyinsalela ukuze kuthuthukiswe ukuguquguquka, okufana nokufutheka kuyinhlangano engalingani. ukulinganisa izinqubo zenhlangano, le nqubo incike ekufudukeni kwe-athomu kanye nokusabalalisa kwalokhu kugunyazwa kanye nezinga lokushisa lomlilo eliqediwe liphezulu, isivinini esisheshayo sokusabalalisa; Ngokuphambene nalokho, ngokwanda kwezinga lokushisa, isakhiwo sokucisha se-forging sizokwenza. bhekana nochungechunge lwezinguquko.Ngokwesimo sokuguqulwa kwe-microstructure, ukushisa kuvame ukuhlukaniswa ngezigaba ezine: ukubola kwe-martensite, ukubola kwe-austenite eyinsalela, ukukhula kokuqoqwa kwe-carbide kanye ne-ferrite recrystallization.
Isigaba sokuqala (200)
(1) ukuqambai-martensite eshisayo ibola ngaphansi kwezinga lokushisa elingu-80, icisha insimbi ngaphandle kokuguqulwa kwe-Ming S, ukwenzeka kwekhabhoni e-martensite ingxenye kuphela, futhi akukho ukuqala ukudiliza ku-80-200 tempering, i-martensite iqala ukubola, idonsa i-carbides ecashile kakhulu, inciphisa ingxenye enkulu ye-martensite ku-carbon forgings kulesi sigaba, ngenxa yezinga lokushisa eliphansi, imvula ye-martensitic ingxenye kuphela yama-athomu ekhabhoni ene-supersaturated, ngakho-ke kuseyikhabhoni e- - Fe supersaturated solution eqinileImvula ye-carbide enhle kakhulu isabalalisa ngokulinganayo ku-matrix. i-martensite.Isakhiwo esixubile sokugcwala okuphansi kwe-Martensite kanye ne-carbide enhle kakhulu ibizwa ngokuthi i- tempered Martensite.

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(2)ukuqambaukufudumala esigabeni sesibili (200-300), ukubola kwe-austenite eyinsalela lapho izinga lokushisa likhuphuka laya ku-200-300, ukubola kwe-martensite kwaqhubeka, kodwa ukuguqulwa okuyinhloko ukubola kwe-austenite eyinsalela yokubola kwe-austenite eyinsalela kwakungokwandiswa kwama-athomu e-carbon. ukwakha indawo eyingxenye, bese ibola ibe yisigaba se-alpha kanye nengxube yenhlangano ye-carbide, okungukuthi ukwakheka kokuqina kwensimbi ye-bainite akunciphisi ngokusobala kulesi sigaba.
(3)Isigaba sesithathu (250-400) sokuguqulwa kwe-carbide ye-forging tempering ikulolu hlu lokushisa.Ngenxa yokushisa okuphezulu, ikhono lokusabalalisa i-Carbon athomu linamandla, amandla okusabalalisa okubuyisela ama-athomu ensimbi futhi, i-martensite ibolisa ukuguqulwa kwe-carbides yemvula kanye nokubola okusele kwe-austenite kuzoguqulwa kube usimende ozinzile ngokuhlukana nokuguqulwa kwama-carbides, ukwehla. ye-martensite ku-carbon mass ingxenyenamba, ukuhlanekezela kwe-martensite lattice kuyanyamalala, ukuguqulwa kwe-martensitic ye-ferrite, thola ukusatshalaliswa kwe-matrix ye-ferritic ngaphakathi kwe-granular encane noma i-lamellar cementite yenhlangano, inhlangano ebizwa ngokuthi i-temering ngokuyisisekelo yaqeda lesi sigaba sokucisha i-austenite ukucindezeleka, ukuqina, ukuqina kwe-plasticity kwathuthukiswa.

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(4)Isigaba sesine se-forging tempering (& GT;400) ikhule i-carbide eqoqiwe futhi i-ferrite iphinda i-crystallization ngenxa yokushisa okushisayo iphezulu kakhulu, ama-athomu e-carbon ne-iron anekhono elinamandla lokusabalala, isigaba sesithathu sokwakheka kwama-cementite flakes azoqhubeka e-spheroidizing futhi akhule. phezulu ngaphezu kuka-500-600, i-alpha recrystallization yenzeka kancane kancane, ilahlekelwe i-ferrite morphology yomugqa wepuleti yasekuqaleni noma ishidi, futhi yakha ukusabalalisa okusanhlamvu kwe-polygon enhlanganweni njenge-ferritic matrix granular carbides, iqembu elibizwa ngokuthi i-temering sorbite tempered sorbite enomshini omuhle obanzi. izakhiwo zesigaba kanye ne-lattice ukuhlanekezela kuqeda ukucindezeleka kwangaphakathi.

(kusuka ku-168 forging net)


Isikhathi sokuthumela: Aug-05-2020

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