(福州大學(xué) 材料科學(xué)與工程學(xué)院，福州 350002)
摘 要: 采用熔煉法制備出新型Fe3Al基−石墨固體自潤滑材料，研究Si含量對(duì)Fe3Al基−石墨固體自潤滑材料的顯微組織、力學(xué)性能以及干摩擦磨損性能的影響。結(jié)果表明：Si可以促進(jìn)C原子在Fe-Al-C液態(tài)合金中熔入及凝固過程中的石墨化，對(duì)Fe3Al基體有固溶強(qiáng)化作用。隨著Si含量增加，C原子的石墨化作用增強(qiáng)，合金的硬度逐漸降低，抗彎強(qiáng)度逐漸增大；但Si合金超過3.5%(質(zhì)量分?jǐn)?shù))時(shí)，由于Si在Fe3Al基體中的過多固溶，三點(diǎn)彎曲強(qiáng)度明顯降低。研究表明，F(xiàn)e3Al基−石墨合金具有高的耐磨性能和良好的潤滑性能，摩擦因數(shù)隨著合金中石墨面密度的增大而降低，磨損率隨Si含量的增加而減小，其中Si含量為3.5%的合金經(jīng)過900 ℃、15 h退火處理后，綜合力學(xué)性能好，其磨損率僅為QT−500球墨鑄鐵的1/20。
關(guān)鍵字: Fe3Al基−石墨合金；固體自潤滑材料；熔煉法；石墨化；摩擦磨損
（School of Materials Science and Engineering, Fuzhou University,Fuzhou 350002, China）
Abstract:Fe3Al−graphite solid self-lubricating materials were prepared by melting method. The effects of Si content on the microscopic structure, mechanical and dry friction properties were investigated. The results show that Si element has an effect on facilitating carbon atoms to solute in Fe-Al-C liquid alloy and to graphitize in the process of solidification, which can solution strengthen the alloy matrix. With increasing Si content, the hardness decreases and the bend strength increases because the the strengthening effect of graphitization. When Si content exceeds 3.5%(mass fraction), the bend strength deduces dramatically because the solution of Si element in Fe3Al matrix is too much. The results also show that Fe3Al−graphite alloy has good wear-resisting and lubricating properties. The coefficient of dry friction decreases with increasing area density of graphite, and the wear rate reduces with increasing Si content. Fe3Al−graphite solid self-lubricating material with 3.5% Si after annealing at 900 ℃ for 15 h has good mechanical properties, and the wear rate is just as 1/20 as that the of spheroidal graphite iron.
Key words: Fe3Al−graphite alloy; solid self-lubricating material; melting; graphitization; friction and wear
