Min XU
,
Minxiu QUAN
,
Zhuangqi HU
,
Y
,
ong WANG
,
Liang ZUO
材料科学技术（英文）
Fe62Co8-xCrxZr6Nb4B20(x=0–4 at. pct) metallic glasses show high thermal stability with a maximum supercooled liquid region of about 84.8 K. The addition of 2 at. pct Cr causes the extension of the supercooled liquid region remarkably, leading to the enhancement of thermal stability and glass-forming ability. The crystallization of the Fe-based glassy alloys takes place through a single exothermic reaction, accompanying the precipitation of more than three kinds of crystallized phases such as α-Fe, Fe2Zr and ZrB2. The long-range atomic rearrangements required for the precipitation of the multiple crystalline phases seem to play an important role in the appearance of the large supercooled liquid region through the retardation of the crystallization reactions. The Fe-based alloys exhibit soft ferromagnetic properties. The saturation magnetization decreases with increasing Cr content while the saturated magnetostriction increases as a function of Cr content. There is no distinct change in the saturation magnetization and coercive force with annealing temperature below the crystallization temperature. The devitrification gives rise to a considerable enhancement in both δs and Hc.
关键词:
Cr addition
,
null
,
null
杭州明
,
邴智刚
,
许恒
,
翁文祥
材料科学与工程学报
采用XRD、SEM-EDS等方法对Ti0.4Zr0.1V1.1 Mn0.5Ni0Crx(x=0,0.1,0.2,0.3)储氢合金的微观结构及电化学性能进行了表征.XRD分析结果表明Ti0.Zr0.iV1.1Mn0.5Ni0.4Crx(x＝0,0.1,0.2,0..3)储氢合金由BCC结构的V基固溶体主相和少量的C14 Laves第二相组成.SEM-EDS分析结果表明,V基固溶体主相为树枝晶结构,C14 Laves相呈网格状沿着主相晶界析出.电化学测试结果表明,Ti0.4Zr0.1V1.1Mn0.5Ni0.Crx(x=0,0.1,0.2,0.3)氢化物电极在303K下,随Cr含量的增加,最大放电容量分别为574.6mAh/g、418.8mAh/g、368.8mAh/g和322.9 mAh/g.当x=0.3时,合金电极在333K下的最大放电容量达到了824.1mAh/g.Cr的添加显著提高了合金电极的高倍率放电性能和循环寿命,40次充放电循环后Ti0.4Zr0.1V1.1Mn0.5Ni0.4Cr0.3合金电极的容量保持率为62.3％.
关键词:
MH/Ni电池
,
V基固溶体
,
Cr添加
,
微观结构
,
电化学性能
张松
,
郭喜平
材料研究学报
采用真空非自耗电弧熔炼的方法制备了4种名义成分为Nb-22Ti-16Si-4Hf-3Al-xCr(x=0,3,5和10,原子分数,％)的合金,并于1450℃保温50 h进行了均匀化处理,研究Cr含量对Nb-Si基超高温合金电弧熔炼态和热处理后组织,及其电弧熔炼态下室温断裂韧性的影响.结果表明:添加Cr没有改变硅化物的晶型(均为γ(Nb,X)Si3),但其含量随Cr含量的增加而增加,而Nbss/γ(Nb,X)5Si3共晶的含量则逐渐降低;添加Cr还促进了 Nbss/(Nb,X)5SiJCr2(Nb,∞三相共晶的形成,且该共晶的含量随合金中Cr含量的增加而增加.经1450℃/50 h热处理后,原电弧熔炼态的Nbss枝晶和共晶组织消失,且合金组织明显变得均匀.Cr含量为0,3％和5％的合金组成相为Nbss和γ(Nb,X)5Si3,而在Cr含量为10％的合金中则出现了Nbss,γ(Nb,X)5Si和Cr2(Nb,X)的三相平衡组织.电弧熔炼态下合金的室温断裂韧性随Cr含量的增加呈现降低的趋势.
关键词:
金属材料
,
Nb-Si基超高温合金
,
电弧熔炼态
,
热处理
,
室温断裂韧性
,
Cr含量
