Fourteen Pt-Al-Nb alloys were made by arc melting and studied in both the as-cast condition and after annealing at 1000 °C for 1000 h, using scanning electron microscopy with energy dispersive x-ray analysis, and x-ray diffraction. A modified electro-etching method was used to etch as-cast alloys which gave much clearer microstructures, by helping to remove the Al oxide scale on the surface. One ternary phase was found, Nb 47.8 Pt 50.3 Al 1.9 (at.%). A solidification projection, liquidus projection surface and 1000 °C isothermal section were derived. The extensions into the ternary on solidification were: ~Nb 2 Pt: ~ 20 at.% Al; ~NbPt 2 : ~ 5 at.% Al; β NbPt 3 : ~ 4 at.% Al; ~PtAl: ~ 2 at.% Nb; ~Pt 5 Al 3 : ~ 5 at.% Nb; ~Pt 3 Al: ~ 10 at.% Nb; and β : ~ 30 at.% Nb. Ten invariant reactions were found on the liquidus surface. The samples were annealed at 1000 °C for 1000 h under air, and while some alloys showed phases with little reduction in extension, some alloys had oxidised to form (Pt) and the oxides of aluminium and niobium.

中文翻译：

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Pt-Al-Nb 合金高于 45 at.% Pt 的研究

14 种 Pt-Al-Nb 合金通过电弧熔炼制成，并在铸态和 1000 °C 退火 1000 小时后进行研究，使用扫描电子显微镜、能量色散 X 射线分析和 X 射线衍射。改进的电蚀刻方法用于蚀刻铸态合金，通过帮助去除表面上的 Al 氧化皮，提供更清晰的微观结构。发现了一种三元相，Nb 47.8 Pt 50.3 Al 1.9 (at.%)。得到了凝固投影、液相线投影面和 1000 °C 等温截面。凝固时延伸到三元中的是：~Nb 2 Pt：~20 at.% Al；~NbPt 2：~5at.% Al；β NbPt 3 ：～4 at.% Al；~PtAl: ~ 2 at.% Nb；~Pt 5 Al 3 ：~5at.% Nb；~Pt 3 Al：~10 at.% Nb；和 β：～30 at.% Nb。在液相线表面上发现了十个不变的反应。