Imbangela yokwehluleka kokuphuka ngemva kwezinyanga ezingu-18 zevalvu yesihlungi sensimbi engagqwali yasebenza izinyanga ezingu-18, futhi ivalve yokuphuka yatholwa futhi yahlaziywa ivalvu yokuphuka, izicubu zesigaba segolide, kanye nokwakheka kwamakhemikhali. Imiphumela ibonisa ukuthi indawo eqhekekile ye-valve iyigobolondo futhi isici sokuhlunga sihlola kabusha isayithi, okungukuthi, ukumelana nengxenye enkulu yokucindezela kwegesi, umthombo wokuguguleka kanye nomthombo wokuqhekeka okuvela empandeni yentambo engaphakathi. , yelulelwe endaweni yangaphakathi yegobolondo le-valve ngaphandle Impahla i-ferrite+martensite izicubu zamazwe amabili, futhi amaphuzu evolumu ye-perchine tissue ngu-15% kuya ku-25%. Ngaphansi komlomo ophukile womzimba we-valve uyisicaba, futhi imifantu phakathi kwezinhlamvu kugcwele, okubonisa izici zezingcezwana ezicwebezelayo. Kukhona ukuphambuka okukhulu kokuqukethwe kwe-CR kanye ne-Ni esakhiweni somzimba we-valve yesihlungi, futhi okuqukethwe kwe-ferrite kukhulu kuno-10%, okunciphisa ukuqina kwepulasitiki kwezinto. Lesi yisici esingokwemvelo ekuhlulekeni kwezinto ezibonakalayo; Ukuguguleka kuxutshwa nesigaba sesibili se-carbon-rich kanye ne-chromium ekubuyiseleni izinto ezibonakalayo, kanye nemifantu endaweni lapho ukugxila kwengcindezi kugxilwe khona. Ngaphansi kwethonya lokucindezeleka okushintshwayo, ukuqhekeka kunwetshwa ngokuqhubekayo, futhi impahla izogcina iphukile.