(中南大學(xué)粉末冶金研究院粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 在Fe-2%Ni-1%Cu-0.6%C混合料中加入了少量微細(xì)Fe2O3粉末作為燒結(jié)助劑，研究Fe2O3粉末的添加量對(duì)混合料的壓縮性、燒結(jié)合金的密度和強(qiáng)度以及氧和碳含量等的影響，研究微細(xì)Fe2O3粉末對(duì)合金的助燒結(jié)行為。結(jié)果表明：混合料中Fe2O3含量大于0.3%(質(zhì)量分?jǐn)?shù))時(shí)，會(huì)導(dǎo)致成形生坯密度下降；當(dāng)Fe2O3添加量為0.3%時(shí)，燒結(jié)合金的密度最高，經(jīng)1120 ℃燒結(jié)0.5和1 h后，合金的抗彎強(qiáng)度比同等燒結(jié)條件下未添加Fe2O3樣品的分別提高6.5%和4.2%。少量Fe2O3粉在材料燒結(jié)時(shí)對(duì)碳含量損失率的影響較小，然而可以降低燒結(jié)體中的氧含量。在壓坯的燒結(jié)過程中，F(xiàn)e2O3還原后于750 ℃左右開始加速基體顆粒間的連結(jié)，雖然在1050 ℃以上時(shí)微細(xì)粉的助燒結(jié)作用減弱，但燒結(jié)體中孔隙更趨于球化。
關(guān)鍵字: 鐵基粉末冶金；Fe-2%Ni-1%Cu-0.6%C；Fe2O3粉；燒結(jié)
（State Key Laboratory of Powder Metallurgy, Research Institute of Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract:Fe-2%Ni-1%Cu-0.6%C powder premix was prepared with minor ultrafine Fe2O3 powder as a sintering aid. The effects of Fe2O3 addition on compressibility of the mixture, sintered density, strength of the alloy and its oxygen and carbon content were studied. The assist-sintering behavior of ultrafine Fe2O3 powder was also investigated. The results show that the green density decreases when the Fe2O3 content is above 0.3%, while the highest density of sintered alloy is obtained with 0.3% Fe2O3 addition.And the flexural strengths of the alloy sintered at 1120 ℃ for 0.5 h and 1 h increase by 6.5% and 4.2%, respectively, compared with that of sample without Fe2O3 powder addition. Minor ultrafine Fe2O3 powder has slight effect on the loss rate of C content of the sintered alloy, and yet the oxygen content is reduced. It is observed that the metallurgy bonding between matrix particles is accelerated from about 750℃ for the reduction of Fe2O3 particles. Though the assist-sintering function of ultrafine powder weakens when the temperature is above 1050 ℃, the pole shape in the sintered alloy is apt to spheroidize.
Key words: iron-based powder metallurgy; Fe-2%Ni-1%Cu-0.6%C; Fe2O3 powder; sintering
