放電容量與顯微結(jié)構(gòu)
(鋼鐵研究總院 功能材料所，北京 100081)
摘 要: 快淬工藝能明顯地提高Ti0.8Zr0.2Mn0.5V0.5Ni1.0貯氫合金的放電容量，而且淬速與放電容量之間在一定情況下出現(xiàn)峰值。XRD、SEM、TEM分析結(jié)果表明：快淬合金由細(xì)小的枝晶組成，隨著淬速增加，晶粒更加細(xì)小；快淬合金很難形成非晶，當(dāng)淬速達(dá)到32m/s時(shí)僅有少量非晶出現(xiàn)，主體仍是微晶和納米晶；Ti0.8Zr0.2Mn0.5V0.5Ni1.0合金是多相結(jié)構(gòu)，低淬速快淬態(tài)合金和鑄態(tài)合金由大量的六方C14 Laves相和少量的TiNi非Laves相組成，當(dāng)淬速達(dá)到8m/s時(shí)，合金中開(kāi)始出現(xiàn)立方C15 Laves相。快淬合金中能大量吸氫的C14、C15相的總含量更多，從而使快淬鈦基合金的放電容量有較大的提高。合金中各個(gè)相的相對(duì)含量隨著淬速的改變而改變，使C14、C15相的總含量與淬速之間并不是簡(jiǎn)單的線性關(guān)系。
關(guān)鍵字: 貯氫合金; 放電容量; 快淬; 顯微結(jié)構(gòu)
（The Functional Material Institute, Central Iron & Steel Research Institute, Beijing 100081, China）
Abstract:The discharge capacity of Ti0.8Zr0.2Mn0.5V0.5Ni1.0 alloy was greatly improved by rapid-quenching, and its peak value can be achieved at certain rapid rate. The microstructure of as-quenching alloy was observed by XRD, SEM and TEM. The results show that: 1) the dendritic crystal will be finer with increasing rapid rate; 2) small quantity of amorphous appears only at the quench rate of 32m/s, the main of alloy still consists of microcrystallite and nanocrystal; 3) both of as-cast alloy and low rate as-quenching alloy are polyphase structure(larger quantity of C14, a little of TiNi), and C15 phase appears under the rate above 8m/s, and more content of C14+C15 phases greatly improves the discharge capacity. With the quenching rate changing, the relative content of each phase is changed, so the relationship between the content of C14+C15 and the rapid quenching rate is not simply lineal.
Key words: hydrogen-storage alloys; discharge capacity; rapid-quenching; microstructure
