Iirivethi zokuqala zaziziipegi ezincinci ezenziwe ngomthi okanye ngethambo. Umzimba wokuqala wokuguqulwa kwesinyithi usenokuba ngukhokho weerivethi esizaziyo. Akukho mathandabuzo ukuba ziindlela zakudala zokudibanisa isinyithi ezaziwa luluntu, ezinokulandelwa emva kokusetyenziswa kwasekuqaleni kwesinyithi esithambileyo. Umzekelo, kwiXesha leBronze, amaYiputa ayerivethi aze abophelele imizimba emithandathu yefeni yomthi yomgca wangaphandle wevili elinezikhewu kunye neerivethi. Emva kokuba amaGrike ephumelele ukwenza imifanekiso emikhulu ngebronze, ayerivethiza iindawo kunye neerivethi. Okwangoku, kukho iintlobo ezininzi zophuhliso lweerivethi, ikakhulu uphuhliso lwamashishini ahlukeneyo.
“Iinxalenye ezisemgangathweni zentsimbi engagqwali” ligama elithile eliquka uluhlu olubanzi lweemveliso. Iinxalenye ezisemgangathweni zentsimbi engagqwali zihlala zisetyenziselwa ukubopha iinxalenye zomatshini ezibizayo ngenxa yobuhle bazo, ukuqina kwazo, ukumelana nokugqwala okunamandla kunye nezinye iimpawu. Ngokuhambela phambili koluntu, iimfuno eziphezulu nazo ziyabekwa phambili kwiinxalenye ezisemgangathweni zentsimbi engagqwali. Iinxalenye ezisemgangathweni zentsimbi engagqwali zikwabhekisa kwizikrufu zentsimbi engagqwali, ezizikrufu ezisemgangathweni. Iinkcukacha, ubukhulu kunye noluhlu lokunyamezelana zonke ziyimigangatho yesizwe.
Izixhobo ezisemgangathweni zentsimbi engagqwaliyo zinemfuno zazo kwizixhobo zokwenza imveliso. Uninzi lwezinto zentsimbi engagqwaliyo zinokwenziwa zibe ziintambo zentsimbi okanye iibhari zokwenza izinto zokuncamathisela, kuquka intsimbi engagqwaliyo ye-austenitic, intsimbi engagqwali ye-ferritic, intsimbi engagqwali ye-martensitic kunye nentsimbi engagqwaliyo yemvula. Ngoko ke zeziphi imigaqo xa ukhetha izinto? Ukukhethwa kwezinto zentsimbi engagqwaliyo kuqwalaselwa kakhulu kwezi zinto zilandelayo:
1. Iimfuneko zeempawu zoomatshini, ngakumbiamandla ezinto zokubopha;
2. Iimfuno zeemeko zokusebenza kwiukumelana nokugqwala kwezinto;
3. Iimfuneko zobushushu obusebenzayo ekumelaneni nobushushu (amandla obushushu aphezulu, ukumelana ne-oxidation) yezinto;
4. Iimfuno zokusebenza kokucubungula izinto ngokwetekhnoloji yemveliso;
5. Ezinye izinto, ezinje ngobunzima, ixabiso kunye nokuthengwa, maziqwalaselwe.
Ixesha lokuthumela: Matshi-16-2023