Effects of Ag on phase transformation of Cu3Sb at high temperatures
Effects of Ag on phase transformation of Cu3Sb at high temperatures
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DOI：
10.1016/j.jpcs.2022.110864
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发表时间：
2022-06
影响因子：
4
通讯作者：
Ryota Yabune;Shunya Shimizu;Masaharu Fujioka;H. Sasaki
中科院分区：
文献类型：
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作者：
Ryota Yabune;Shunya Shimizu;Masaharu Fujioka;H. Sasaki
通过扫描电子显微镜、能谱和高温X射线衍射仪研究了Ag对Cu3Sb相变的影响。对经5 0 0℃热处理的CuSb-Ag合金的观察表明，Ag在立方β-Cu3Sb相中的固溶度高达11at.%，只有在高温下才稳定。X-射线衍射仪证实，β-Cu3Sb相在4 4 0℃发生了由ε-Cu3Sb相向正交晶系β-Cu3Sb相的转变，而在含5%Ag的合金中，这一转变发生在380℃以下，表明Ag的存在提高了合金的稳定性。此外，在4 2 0°C以上对成分与含8-14%Ag(即x=0.32-0.5 6)的Cu3−xAgxSb的合金进行测量时，观察到在5 0 0℃时形成了具有六方结构的新的合金相(a=4.3416，c=7.6864)。新合金相的晶体结构为Na3As型，属于P6 3/mmc空间群。根据对不同成分合金的观察，绘制了5 0 0℃下的CuSb Ag三元相图的等温截面。
Abstract Effects of Ag on the phase transformation of Cu 3 Sb were investigated through scanning electron microscopy, energy-dispersive X-ray spectroscopy, and high-temperature X-ray diffraction (XRD) measurements. Observations of Cu–Sb–Ag alloys following heat treatment at 500° C revealed that Ag dissolved up to 11 at.% in a cubic β-Cu 3 Sb phase stable only at high temperatures. XRD measurements confirmed that while a transformation from the β-Cu 3 Sb phase to orthorhombic ε-Cu 3 Sb phase occurred at 440° C in the binary system, the transformation occurred below 380° C in the alloy containing 5% Ag, suggesting the enhanced stability of the β-Cu 3 Sb phase owing to Ag. Furthermore, during measurements above 420° C on alloys with a composition consistent with that of Cu 3− x Ag x Sb containing 8–14% Ag (ie, x= 0.32–0.56), the formation of a new alloy phase with a hexagonal structure (a= 4.3416 Å and c= 7.6864 Å at 500° C) was observed. The crystal structure of the new alloy phase was inferred to be of the Na 3 As type, which belongs to the space group P 6 3/m m c. Based on observations of alloys with various compositions, an isothermal section of the Cu–Sb–Ag ternary phase diagram at 500° C was constructed.