( 1. 內(nèi)蒙古科技大學(xué) 材料學(xué)院， 包頭 014010;
2. 鋼鐵研究總院 功能材料研究所， 北京 100081)
摘 要: 對(duì)AB5型LaxMm1-x(NiMnSiAlFe)4.9(x=0, 0.45, 0.75, 1.00， 摩爾分?jǐn)?shù))貯氫合金進(jìn)行了快淬處理， 研究了La含量及快淬工藝對(duì)合金微觀結(jié)構(gòu)及電化學(xué)循環(huán)穩(wěn)定性的影響。 結(jié)果表明： La含量的增加對(duì)鑄態(tài)合金的循環(huán)穩(wěn)定性沒有明顯影響，但使快淬態(tài)合金的循環(huán)穩(wěn)定性下降， 且快淬處理能顯著提高合金的循環(huán)穩(wěn)定性。 當(dāng)La替代量從0增加到1.00時(shí)， 經(jīng)300次充放循環(huán)后，鑄態(tài)合金的容量保持率（Rh）從59.2%增加到59.8%； 16 m/s淬速快淬態(tài)合金的容量保持率從83.9%下降到65.0%。 對(duì)于x=0.45的合金，當(dāng)淬速從0(鑄態(tài)被定義為淬速等于0)增加到28 m/s時(shí)，容量保持率從59.8%增加到75.8%。
關(guān)鍵字: 無鈷AB5型貯氫合金； 快淬工藝； 微觀結(jié)構(gòu)；循環(huán)穩(wěn)定性
storage alloy prepared by casting and
rapid quenching
GUO Shi-hai1, REN Jiang-yuan2, WANG Xin-lin1
（ 1. School of Materials, Inner Mongolia University of Science and Technology,
Baotou 014010, China;
2. Institute of Functional Material Research,
Central Iron and Steel Research Institute, Beijing 100081, China）
Abstract: In order to improve the electrochemical cycle stability of the Co-free AB5-type hydrogen storage alloy, Co-free LaxMm1-x(NiMnSiAlFe)4.9 (x=0, 0.45, 0.75, 1.00, mole fraction) hydrogen storage alloys were treated by rapid quenching. The effects of the substituting Mm with La and the quenching rate on the microstructure and the electrochemical cycle stability of the as-cast and quenched alloys were investigated. The obtained results show that the influence of substituting Mm with La on the cycle stability of the as-cast alloys is insignificant, but its influence on that of the as-quenched alloys is notable, and rapid quenching can remarkably enhance the cycle stability of the alloys. When the amount of substituting Mm with La increases from 0 to 1.00, the capacity retaining rate (Rh) of as-cast alloys increases from 59.2% to 59.8% after 300 charge-discharge cycles with the current density of 300 mA/g, and for the as-quenched (16 m/s) alloy, it decreases from 83.9% to 65.0%. When the quenching rate increases from 0 (the as-cast is defined as the quenching rate of 0 m/s) to 28 m/s, the capacity retaining rate (Rh) of La0.45 alloy increases from 59.8% to 75.8%.
Key words: Co-free AB5-type hydrogen storage alloy; rapid quenching; microstructure; cycle stability
