Zithini iimfuno zentsimbi xa kucinywa ubushushu?

Isinyithi sokucima ngaphakathi ukufudumeza iziko ngokubanzi inezi mfuno zilandelayo:

1) Umxholo wekhabhoni wentsimbi umiselwe ziimeko zokusebenza kwezahlulo, kwaye w (C) unokuba yi-0.15% ukuya kwi-1.2%, eyona yona mfuneko iphambili.

2) Isinyithi kufuneka sibe notyekelo lweenkozo ze-austenite ekungekho lula ukuba zikhule, kwaye kufuneka kukhethwe intsimbi enobungakanani obucolekileyo.

3) Isinyithi kufuneka sibe nesakhiwo esihle kwaye sichithakele kwangoko kangangoko kunokwenzeka. Oku kungasentla, 2) no-3) iimeko ezimbini zenza ukuba intsimbi ifumane iinkozo ze-austenite entle kunye nobushushu obuphezulu bokukhula kokutya okuziinkozo ngexesha lokufudumeza. Oku kubaluleke ngakumbi ngexesha lokufudumeza ngaphakathi, kuba ukufudumeza ngokungenisa kuphezulu kunobushushu bokushushu eziko. Kunzima ukulawula ngokuchanekileyo imigaqo yeqondo lobushushu. Okwangoku, jikelele ukufudumeza iziko ukucima isinyithi, ubungakanani beenkozo bulawulwa ngo-5 ukuya ku-8.

Induction ukufudumeza isithando somlilo sineemfuno zonyango lokuqala lwentsimbi. Xa unyango lokuqala lobushushu lucinyiwe kwaye luchukumise izinto ezifanayo zentsimbi, kuba i-sorbite sisakhiwo esihle kakhulu, inguqulelo ye-austenite yeyona ikhawulezayo, kwaye ubushushu obufunekayo bubushushu, obukhokelela kubunzima obufunyenwe Owona uphezulu, ubunzulu obunzulu Uluhlu oluqinileyo luyafumaneka. Xa unyango lokuqala lobushushu luqhelekile, ukuguqulwa kwepearlite entle ye-flake kwi-austenite kufuna ubushushu obuphezulu; xa ulwakhiwo lwantlandlolo luyi-pearlite erhabaxa kunye ne-ferrite eninzi (i-hypoeutectoid state annealing state), emva koko kufuneka ubushushu obuphezulu bokufudumeza. Nangona kunjalo, ngenxa yexesha elifutshane lokufudumeza, kusaya kubakho i-ferrite engachazwanga kulwakhiwo olucinywayo. Xa ucima kwiziko lokufudumeza ubushushu, ubulukhuni bentsimbi busadlala indima. Kwangokunjalo, xa umaleko wokufudumeza ubunzulu, ukucoceka kwesakhiwo, kokukhona kunzima ukuqina, kunye nezinto zokudibanisa eziqulathwe kwisinyithi, ezinje nge-Mn (manganese), Cr (chromium), Ni (nickel), Mo (molybdenum), njl. zinempembelelo ethile kubukhuni bentsimbi.

4) Umxholo wekhabhoni okhethiweyo. Kwamanye amalungu abalulekileyo anjengee-crankshafts, i-camshafts, njl., Xa ukhetha amabakala esinyithi, iimfuno ezongezelelweyo zomxholo wekhabhoni okhethiweyo zihlala zibekwa phambili. I-0.08% (enje nge-0.42% ukuya kwi-0.50%) incitshisiwe yaya kwi-0.05% yeebanga (ezinje nge-0.42% ukuya kwi-0.47%), ezinokuthi zinciphise ifuthe lokuguquguquka komxholo wekhabhoni kuqhekeko okanye kutshintsho lobunzulu bomaleko. Umbhali uhlalutye i-45 yentsimbi kwimithombo eyahlukeneyo yokucima i-crankshaft entongweni yokufudumeza isithando somlilo, kwaye wafumanisa ukuba phantsi kwenkqubo efanayo yokucaciswa, ubunzulu boluhlu bohluke kakhulu. Isizathu sihambelana ne-Mn yezixhobo kunye nomxholo we-Cr kunye ne-Ni kumdaka. . Ukongeza, phakathi kwezinto ezingafunekiyo zentsimbi yangaphandle, umxholo weCr no-Ni uhlala uphezulu kunalowo wentsimbi yasekhaya. Ke ngoko, iziphumo zokucima zihlala zahlukile. Le ngongoma kufuneka ihlawulwe.

5) Ubunzulu be-Decarburization yeentsimbi ezibandayo. Xa intsimbi ebandayo etsalwa isetyenziselwa ukucima i ukufudumeza iziko, Kukho iimfuno zobunzulu be-decarburization ephezulu. Ngokubanzi, ubunzulu be-decarburization ubuninzi kwicala ngalinye kufuneka ibe ngaphantsi kwe-1% yedayara yebar okanye ubukhulu bepleyiti yesinyithi. Ukuqina kobunzima bekhabhoni obucekeceke buphantsi kakhulu emva kokucima, intsimbi ebandayo ebandayo kufuneka ibe ngumhlaba ukuze isuse umaleko wekhabhoni ngaphambi kokuba ujonge ukuqina kobunzima.