(1. 中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083；
2. 中南大學(xué) 資源循環(huán)研究院，長沙 410083)
摘 要: 傳統(tǒng)的克勞爾方法制備鋯鈮合金存在工藝流程長、易被雜質(zhì)元素污染等問題。本文提出一種利用氫氣輔助鎂還原-壓制燒結(jié)直接制備鋯鈮合金的新工藝。以Zr-2.5Nb為目標(biāo)合金，在氫氣氣氛下利用鎂粉還原金屬氧化物ZrO2和Nb2O5的混合物，成功制備出氧質(zhì)量分?jǐn)?shù)低至0.038%的Zr-2.5Nb氫化合金粉末，之后對制備出的合金粉末進(jìn)行冷等靜壓-燒結(jié)，制備Zr-2.5Nb合金。對制備出的合金粉末的元素含量、形貌及粒度進(jìn)行了分析，探究了燒結(jié)溫度對合金性能的影響。結(jié)果表明：合金粉末中Nb質(zhì)量分?jǐn)?shù)為2.29%，平均粒度為61.88 μm。當(dāng)燒結(jié)溫度為1400 ℃時(shí)，合金產(chǎn)品致密度和硬度分別達(dá)到最大，分別為95.36%和250.3 HV，合金的壓縮強(qiáng)度在1300 ℃時(shí)達(dá)到最高值1059 MPa。制備出的合金硬度和壓縮性能均滿足美國工業(yè)核級鋯合金標(biāo)準(zhǔn)。
關(guān)鍵字: 還原；Zr-Nb合金；粉末；燒結(jié)
（1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. Research Institute of Resource Recycling, Central South University, Changsha 410083, China）
Abstract:The traditional Kroll method for preparing zirconium alloy has a long process and is easy to be polluted by impurity elements. In this paper, a new method for directly preparing alloy by sintering Zr-Nb alloy powder via hydrogen assisted magnesium thermal reduction of metal oxide was proposed. Taking Zr-2.5Nb as the target alloy, Zr-2.5Nb hydrogenated alloy powder with 0.038% oxygen content was successfully prepared by reducing the mixture of ZrO2 and Nb2O5 with magnesium powder in hydrogen atmosphere first. After that, Zr-2.5Nb alloy was prepared by cold isostatic and sintering. The results show that the oxygen content in the alloy powder is only 0.038% and the Nb content is 2.29%. At a sintering temperature of 1400 ℃, the maximum densification degree of alloy products is 95.36% and the maximum hardness is 250.3 HV. However, the compressive strength of the alloy decreased from 1059 MPa sintered at 1300 ℃ to 978 MPa sintered at 1400 ℃. The hardness and compressibility of the prepared alloy meet the American Standard of nuclear grade industrial zirconium alloy.
Key words: reduction; Zr-Nb alloy; powder; sintering
