Ukucima, okukwabizwa ngokuba kukuqina yinkqubo yokufudumeza nokupholisa intsimbi (okanye enye i-alloy) ngesantya esiphezulu kangangokuba kukho ukwanda okukhulu kobunzima, nokuba kumphezulu okanye kuyo yonke indawo. Kwimeko yokucima nge-vacuum, le nkqubo yenziwa kwii-vacuum oven apho amaqondo obushushu afikelela kwi-1,300°C anokufikelelwa khona. Iindlela zokucima ziya kwahluka ngokubhekiselele kwizinto ezicociweyo kodwa ukucima ngegesi kusetyenziswa i-nitrogen yeyona ixhaphakileyo.
Ukucima igesi nge-vacuum:
Ngexesha lokucima igesi ye-vacuum, izinto ziyafudunyezwa xa kungekho oxygen nge-convection kwi-medium yegesi engangeniyo (N₂) kunye/okanye i-radiation yobushushu kwi-underpressure. Intsimbi iyaqiniswa ngomjelo we-nitrogen, apho izinga lokupholisa linokuqinisekiswa ngokukhetha uxinzelelo olugqithisileyo. Ngokuxhomekeke kwimilo ye-workpiece, kunokwenzeka ukukhetha indlela kunye nexesha lokuvuthela i-nitrogen. Ukulungiswa kwexesha kunye nolawulo lobushushu bentsimbi kwenziwa ngexesha lenkqubo ngokusebenzisa ii-thermocouples ze-pilot ezinokubekwa kwi-workpiece kwigumbi lokufudumeza. Intsimbi ephathwa ngobushushu kwi-vacuum oven ifumana iimpawu ezithile zamandla kunye nobunzima kuyo yonke indawo, ngaphandle kokususa i-carburization kumphezulu. I-Austenitic grain ilungile kwaye ihambelana nemigangatho yamazwe ngamazwe.
Phantse zonke ii-alloy zentsimbi ezinomdla kwezobuchwepheshe, ezifana neentsimbi zasentwasahlobo, iintsimbi ezibandayo, iintsimbi ezicinyiweyo neziqinisiweyo, iintsimbi ezilwa nokungqubana, iintsimbi ezishushu kunye neentsimbi zezixhobo, kunye nenani elikhulu leentsimbi ezingenasici ezine-alloy ephezulu kunye nee-alloy zesinyithi, zinokuqina ngale ndlela.
Ukucima ioyile yokucoca umoya
Ukucima iOyile yeVacuum kukupholisa izinto ezishushu ngeOyile yeVacuum. Njengoko ukudluliselwa kwetshaja kusenzeka phantsi kokhuseleko lwevacuum okanye igesi engasebenziyo emva kokuba sicoce i-furnace, umphezulu wenxalenye uhlala ukhuselekile de untywiliswe ngokupheleleyo kwioyile. Ukhuseleko lomphezulu lufana kakhulu nokuba kukucima kwioyile okanye kwigesi.
Eyona nzuzo inkulu xa ithelekiswa nezisombululo zesiqhelo zokucima ioyile emoyeni kukulawula ngokuchanekileyo iiparameter zokupholisa. Ngesithando somoya, kunokwenzeka ukutshintsha iiparameter zokucima eziqhelekileyo - ubushushu kunye nokushukuma - kunye nokutshintsha uxinzelelo olungaphezulu kwetanki yokucima.
Ukutshintsha uxinzelelo olungaphezulu kwetanki kuya kubangela umahluko kuxinzelelo ngaphakathi kwebhafu yeoyile, nto leyo etshintsha indlela esebenza ngayo i-oyile-cooling curve echazwe kuxinzelelo lomoya. Enyanisweni, indawo yokubilisa yinqanaba apho isantya sokupholisa siphezulu. Utshintsho kuxinzelelo yeoyile luya kutshintsha ukufuma kwayo ngenxa yobushushu bomthwalo.
Ukunciphisa uxinzelelo kuya kuqalisa i-vaporization phenomena, eqala isigaba sokubila. Oku kuya kwandisa ukusebenza kakuhle kokupholisa kokucima ulwelo kwaye kuphucule amandla okuqina xa kuthelekiswa nemeko yomoya. Nangona kunjalo, ukuveliswa okukhulu komphunga kunokubangela i-sheath phenomena kwaye kubangele ukuguquguquka okunokwenzeka.
Ukwanda koxinzelelo kwioyile kuthintela ukwakheka komphunga kwaye kuthintele ukufuma. I-sheath inamathela kwinxalenye kwaye iphola ngokulinganayo kodwa kancinci kakhulu. Ukucima ioyile kwi-vacuum ke ngoko kuyafana ngakumbi kwaye akunampembelelo ingako.
Ukucima amanzi nge-vacuum
Inkqubo efana nokucima ioyile ye-vacuum, sisisombululo esifanelekileyo sokulungisa ubushushu be-aluminium, i-titanium okanye ezinye izinto ezifuna ukuphola ngesantya esikhawulezayo ngokwaneleyo.
Ixesha lokuthumela: Meyi-07-2022