Answer
Black Oxide (MIL-DTL-13924) shafi ne na jujjuyawa da aka samar ta hanyar sinadarai tare da saman karfen carbon. Ba kamar wutar lantarki ba, baya canza girman zoben da muhimmanci (yawanci $< 0.00001$ inci) kuma, mafi mahimmanci, baya gabatar da Haɗaɗɗen Hydrogen. Duk da yake yana ba da juriya na ɓarna kawai (ƙididdigewa na kimanin sa'o'i 24-96 a cikin gishiri mai fesa da mai), yana da kyau ga majalissar injina na ciki inda aka nutsar da zobe a cikin mai. Har ila yau, yana ba da yanayin da ba a nunawa ba kuma yana ƙara yawan lubric na zobe, wanda ke taimakawa wajen shigarwa kuma yana rage haɗarin galling a cikin tsagi.