Ukwelashwa kokushisa ngamakhemikhali kokusakazwa kwensimbi kubhekisela ekubekeni ukusakaza endaweni esebenzayo ezingeni lokushisa elithile ukuze kugcinwe ukushisa, ukuze izakhi zamakhemikhali eyodwa noma ezimbalwa zingene phezulu. Ukwelashwa kokushisa kwamakhemikhali kungashintsha ukwakheka kwamakhemikhali, ukwakheka kwe-metallographic kanye nezakhiwo zemishini ebusweni bokuphonsa. Izinqubo ezivame ukusetshenziswa zamakhemikhali zokwelapha ukushisa zihlanganisa carburizing, nitriding, carbonitriding, boronizing kanye metalizing. Lapho kwenziwa ukwelashwa kokushisa kwamakhemikhali ekubunjweni, ukwakheka, usayizi, isimo esingaphezulu, kanye nokwelashwa kokushisa okungaphezulu kokusakazwa kufanele kucatshangelwe ngokugcwele.
1. Carburizing
I-Carburizing ibhekisela ekushiseni nasekugqumeni ukusakaza endaweni yokungcwaba, bese ifaka ama-athomu ekhabhoni phezulu. Inhloso eyinhloko ye-carburizing ukukhulisa okuqukethwe kwekhabhoni ebusweni bokusakaza, kuyilapho kwakhiwa i-gradient ethile yokuqukethwe kwekhabhoni ekubunjweni. Okuqukethwe kwekhabhoni yensimbi ye-carburizing ngokuvamile kungu-0.1% -0.25% ukuze kuqinisekiswe ukuthi umnyombo wokuphonsa unokuqina namandla okwanele.
Ukuqina kobuso bengqimba ye-carburized ngokuvamile ku-56HRC-63HRC. Isakhiwo se-metallographic sengqimba ye-carburized iyinaliti enhle ye-martensite + inani elincane le-austenite egciniwe kanye ne-granular carbides esatshalaliswa ngokulinganayo. Ama-carbides enethiwekhi awavunyelwe, futhi ingxenye yevolumu ye-austenite egciniwe ngokuvamile ayidluli i-15% -20%.
Ukuqina okuyisisekelo kokusakazwa ngemuva kokungcwatshwa kwe-carburizing ngokuvamile kungu-30HRC-45HRC. Isakhiwo se-metallographic esiyinhloko kufanele sibe i-low-carbon martensite noma i-bainite ephansi. Ayivunyelwe ukuba ne-ferrite enkulu noma enamanzi eduze komngcele wokusanhlamvu.
Emkhiqizweni wangempela, kunezindlela ezintathu ezijwayelekile zokungcwaba: i-carburizing eqinile, i-liquid carburizing kanye ne-gas carburizing.
2. I-Nitriding
I-Nitriding ibhekisela kunqubo yokwelapha ukushisa engenisa ama-athomu e-nitrogen ebusweni bokubunjwa. I-Nitriding ngokuvamile yenziwa ngaphansi kwezinga lokushisa le-Ac1, futhi inhloso yayo eyinhloko ukuthuthukisa ubulukhuni, ukumelana nokugqokwa, amandla okukhathala, ukumelana nokubanjwa kanye nokumelana nokugqwala komkhathi kwendawo yokuphonsa. Ukufakwa kwe-nitriding yensimbi ngokuvamile kwenziwa ku-480°C-580°C. Ukusakaza okuqukethe i-aluminium, i-chromium, i-titanium, i-molybdenum, ne-tungsten, njengensimbi ye-alloy ephansi, insimbi engagqwali, nensimbi yensimbi yokubumba eshisayo, kulungele i-nitriding.
Ukuze kuqinisekiswe ukuthi umnyombo wokuphonsa unezakhiwo ezidingekayo zemishini kanye nesakhiwo se-metallographic, futhi ukunciphisa ukubola ngemva kwe-nitriding, ukwelashwa kwangaphambili ngaphambi kwe-nitriding kuyadingeka. Ngensimbi yesakhiwo, ukwelashwa kokucisha kanye nokushisa kuyadingeka ngaphambi kwe-nitriding ukuze kutholwe iyunifomu kanye nesakhiwo esihle se-sorbite; kuma-castings ahlanekezelwa kalula ngesikhathi sokwelashwa kwe-nitriding, ukwelashwa kwe-annealing yokunciphisa ukucindezeleka kuyadingeka ngemva kokucisha kanye nokushisa; okwensimbi engagqwali kanye nezinsimbi zensimbi ezikwazi ukumelana nokushisa ngokuvamile zingacinywa futhi zifutheke ukuze kuthuthukiswe ukwakheka namandla; ngensimbi engagqwali ye-austenitic, ukwelashwa kokushisa kwesisombululo kungasetshenziswa.
Isikhathi sokuthumela: Jul-21-2021