摘要
采用电弧加热蒸发法制备出粉末粒度在5nm～30nm的Ti-Fe系合金纳米粉末,研究了纳米粉末的相生成规律以及混合物粉末的尺寸效应。实验结果表明,纳米粉末中化合物相的生成规律与Ti-Fe合金平衡相图的不同。蒸发Fe含量大于73%(质量分数,下同)的母合金时易得到FCC相和Fe2Ti相,而蒸发Ti含量大于47%的母合金易得到以FCC相和FeTi相为主的粉末,且所有粉末中FCC相含量最多。当母合金中Fe含量为53%时,粉末中FeTi相的相对含量是所有粉末中最高的。只有在蒸发Ti含量为90%的母合金所得的粉末中检测到了少量Ti单质相。FCC相的d(111)晶面间距随母合金中Ti含量的增加而增加,说明FCC为固溶体相。DSC结果表明,纳米粉末的平均熔点明显低于粉末中各个合金相在平衡状态下的熔点。
Ti-Fe alloy nanometer powders with particle size between 5 nm-30 nm were prepared by gas evaporation with arc as a heating source. The formation regularities of the phases and the melting point of the powers were investigated. The results indicate that the as-formed alloy phases in the nanometer powders are different from that in the Ti-Fe equilibrium phase diagram. FCC and TiFe2 phases were easily obtained when the master alloy rich in Fe was evaporated; by contrast, we gained FCC and TiFe phases when the master alloy rich in Ti were evaporated. The relative amount of the FCC phase is always the highest in all the powder samples. As the component of Fe in the master alloy is 53wt%, the relative amount of FeTi phase in the as-prepared powder was the highest among all the samples. A little amount of Ti phase was detected in the nanometer powders only when the Fe 10Ti90 master alloy was evaporated due to the formation of the FCC phase. The lattice spacing of d（111） plane of FCC phase increased with the increase of Ti amount in the master alloys, which confirmed the solution of the Ti in the phase. The D SC curves showed that the mean melting points of these nanometer powders were lower than that of the as-formed alloy phases at equilibrium state.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2007年第2期250-254,共5页
Rare Metal Materials and Engineering
基金
国家自然科学基金(50304008)
博士点基金(20030532016)
博士后基金项目资助(2004035642)
