(東北大學(xué) 材料與冶金學(xué)院, 沈陽 110004)
摘 要: 分別采用3種不同鎂含量的鎂鋁合金對GCr15軸承鋼液進行了夾雜物變質(zhì)處理， 分析了實驗過程中全氧值的變化， 并利用光學(xué)顯微鏡、 掃描電鏡和能譜儀分析了試樣中夾雜物的尺寸、形貌和化學(xué)成分。 結(jié)果表明： 經(jīng)鎂鋁合金處理后， GCr15軸承鋼中的全氧值顯著降低， 夾雜物由大尺寸、 形狀不定的氧化鋁顆粒轉(zhuǎn)變?yōu)槌叽缂毿 ⑶蛐蔚逆V鋁尖晶石顆粒。 含鎂量為16.55%的3#鎂鋁合金夾雜物變質(zhì)效果最明顯，鋼中夾雜物多為鎂鋁尖晶石和氧化鎂， 其中96.23%的夾雜物直徑小于3 μm。 因此， 鎂鋁合金夾雜物變質(zhì)處理有利于改善軸承鋼澆注和提高軸承鋼疲勞壽命。
關(guān)鍵字: GCr15軸承鋼； 鎂鋁合金； 夾雜物； 變質(zhì)處理
（School of Materials and Metallurgy,
Northeastern University, Shenyang 110004, China）
Abstract: The molten GCr15 bearing steel was modified by three types of Al-Mg alloys. Firstly, the total oxygen content value was measured, then the inclusion size, shape and chemical composition were analyzed by optical microscopy, SEM and EDX. The results show that, after treated by Al-Mg alloy, the total oxygen content descends remarkably and the alumina inclusion with big size and different shapes transform into spinel with small size and spherical shape. The optimal effect of inclusion modification is acquired after treated by 3# Al-Mg alloy containing 16.55% Mg, most of the inclusions in steel are spinel and magnesia, and the size of 96.23% inclusions is less than 3 μm. So, the inclusion modification treated by Al-Mg alloy can improve casting and fatigue life of bearing steel.
Key words: GCr15 bearing steel; Al-Mg alloy; inclusion; modification treatment
