低价氯化钛浆料直接电化学还原制备钛铝合金新工艺研究
A new process for preparing Ti-Al alloys from low-valance titanium chlorides slurry by direct electrochemical reduction
朱福兴 1马占山 2邓斌 3穆天柱 3邱克辉4
作者信息
- 1. 钒钛资源综合利用国家重点实验室,攀钢集团研究院有限公司,四川攀枝花 617000;成都理工大学材料与化学化工学院,四川成都 610059
- 2. 钒钛资源综合利用国家重点实验室,攀钢集团研究院有限公司,四川攀枝花 617000;上海大学材料科学与工程学院,上海 200444
- 3. 钒钛资源综合利用国家重点实验室,攀钢集团研究院有限公司,四川攀枝花 617000
- 4. 成都理工大学材料与化学化工学院,四川成都 610059
- 折叠
摘要
针对低价氯化钛(LTC)浆料熔盐电解制备钛铝合金存在的电化学行为研究不系统、合金产品的高温抗氧化特性不明晰等问题,采用电化学工作站、示差热重分析仪等手段对LTC浆料在熔盐体系中电化学行为及合金产品的高温抗氧化特性进行研究.结果表明,LTC浆料在熔盐体系中可直接电化学还原制备Ti-Al合金,且为逐级还原的历程:Ti3+→Ti2+,Al3+→Al,Ti3+/Al3+→Ti-Al合金和Ti2+→Ti;随着熔盐体系中Ti3+离子浓度的增加,钛铝合金的组成变化规律为:Al/Al3Ti-Al3Ti2/Al5Ti2→AlTi/Al0.64Ti0.36→Al0.64Ti0.36/AlTi3→AlTi3→AlTi3/Ti→Ti,产品形貌变化规律为:粗枝晶→细枝晶→细球状结构→粗球状团聚体→细球状团聚体→细球多孔状→多孔状结构.钛铝合金中随着铝含量和产品致密性的增加,合金的抗高温氧化性能逐渐增强,Al0.64Ti0.36/AlTi3合金经高温熔炼后呈Al含量更高的α2/γ和γ组织,使其高温抗氧化性能优于商用Ti48Al2Cr2Nb.钛铝合金产品高温氧化历程为:Ti-Al合金→铝酸钛→金红石/氧化铝,并且形成的氧化物层可有效防止钛铝合金的进一步氧化.
Abstract
Owing to the lack of systematic research on electrochemical behaviors and unclear high-tem-perature oxidation resistance characteristics of Ti-Al alloys prepared from low-valence titanium chlor-ides slurry by the electrochemical reduction in molten salt,the electrochemical workstation and differ-ential thermal gravimetric analyzer were used to study the electrochemical behavior of LTC slurry in the molten salt system and the high-temperature oxidation resistance characteristics of alloy products.The results show that LTC slurry can be directly electrochemically reduced to Ti-Al alloys,following a step-by-step reduction process:Ti3+→Ti2+,Al3+→Al,Ti3+/Al3+→Ti-Al alloys,and Ti2+→Ti.As the concentra-tion of Ti3+ions in molten salts increases,the composition of Ti-Al alloys changes as follows:Al/Al3Ti→Al3Ti2/Al5Ti2→AlTi/Al0.64Ti0.36→Al0.64Ti0.36/AlTi3→AlTi3→AlTi3/Ti→Ti.The variation law of product morphology is as follows:coarse dendrite→fine dendrite→fine spherical structure→coarse spherical aggregate→fine spherical aggregate→fine spherical porous structure→porous structure.With the increase of aluminum content and product density in Ti-Al alloys,the high-temperature oxidation resistance gradually enhances.After high-temperature melting,Al0.64Ti0.36/AlTi3 alloy shows α2 and y phase structures with a higher Al content,and its high-temperature oxidation resistance is superior to commercial Ti48Al2Cr2Nb.The high-temperature oxidation process of Ti-Al alloys is as follows:Ti-Al alloys→titanium aluminate→rutile/alumina,and the formed oxide layer can effectively prevent further oxidation.
关键词
钛铝合金/低价氯化钛浆料/电化学还原/高温抗氧化性Key words
Ti-Al alloys/low-valance titanium chlorides slurry/electrochemical reduction/high tem-perature oxidation resistance引用本文复制引用
基金项目
国家重点基础研究发展计划(973计划)(2013CB632600)
出版年
2024
国家科技期刊平台
NSTL
万方数据