(1. 湘潭大學(xué) 機械工程學(xué)院，湘潭 411105；
2. 湘潭大學(xué) 焊接機器人及應(yīng)用技術(shù)湖南省重點實驗室，湘潭 411105；
3. 中南大學(xué) 粉末冶金國家重點實驗室，長沙 410083)
摘 要: 采用元素粉末反應(yīng)合成法, 利用固相偏擴散的原理進行固相燒結(jié)制備Ni-Cr-Fe多孔材料。通過表征多孔材料在不同燒結(jié)溫度下的膨脹率、孔結(jié)構(gòu)變化及物相組成研究材料的成孔過程，探討造孔機理；并研究Ni-Cr-Fe多孔材料在1000 ℃下的高溫抗氧化性能。結(jié)果表明：Ni-Cr-Fe在1380 ℃下達(dá)到最大膨脹，最大徑向膨脹率達(dá)7%，開孔隙率為32.5%；最大孔徑與透氣度分別為90 μm和990 m3/(m2？kPa？h)。Cr、Fe 元素向Ni元素的偏擴散形成大量豐富孔隙。在氧化實驗中，在1000 ℃高溫下氧化560 h后多孔Ni-Cr-Fe最大孔徑及透氣度變化不大，而同等條件下氧化的Ni-Fe、Ni-Cr多孔材料孔結(jié)構(gòu)變化較明顯，表明Ni-Cr-Fe多孔材料具有優(yōu)異的高溫抗氧化性能。
關(guān)鍵字: Ni-Cr-Fe多孔材料；造孔機理；反應(yīng)合成法；抗氧化性能
（1. School of Mechanical Engineering, Xiangtan University, Xiangtan 411105, China;
2. Key Laboratory of welding robot and application technology of Hunan Province, Xiangtan University, Xiangtan 411105, China;
3. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The porous Ni-Cr-Fe alloys were prepared by reactive powder synthesis method, which used the principle of partial diffusion in solid phase sintering. The expansion rate, changes of pore structure and phase composition of porous Ni-Cr-Fe alloys under different sintering temperatures were characterized to research the pore forming process and explore the mechanism of pore. And the high temperature oxidation resistance of porous Ni-Cr-Fe alloys at 1000 ℃ was studied. The results show that the radial direction expansion has the largest value after being sintered at 1380 ℃ and the values is 7%. The open porosity of the materials is 32.5%, the maximum pore size and the permeability of the materials are 90 μm and 990 m3/(m2？kPa？h), respectively. The large amounts of pores form due to the partial diffusion of Cr and Fe elements into Ni. In the oxidation experiments, the maximum pore size and permeability of Ni-Fe and Ni-Cr with oxidation for 560 h change more obviously than those of Ni-Cr-Fe porous material under the same conditions which indicates that Ni-Cr-Fe porous alloys have excellent high temperature oxidation resistance.
Key words: porous Ni-Cr-Fe alloy; pore-forming mechanism; reaction synthesis; oxidation resistance
