Abstract

The paper presents the results of the long-term experiment on the solid-phase transformation of the Au–Pb metallic system which takes place at room and cryogenic temperatures. It is found that the solid-phase contact interactions between lead and gold lead to the formation of the Pb + AuPb₃ eutectoid. The mass transfer and the phase formation are due to the lead extrusion along the percolation channels that form as a result of the substructural destruction of gold. No reaction layer forms at the boundary of the contacting metals. The decomposition of the solid solutions based on intermetallics AuPb₃ occurs through the process of the destructurization of the material into nanoparticles, the displacement of impurity atoms from the bulk to the boundaries, the integration and ordering of separated components of the solid solution. The decomposition of the AuPb₃ intermetallic compound leads to the formation of AuPb₂ and the phases of variable compositions, and, then, pure components Au + Pb. The decomposition occurs through the stage of fast growth of lead crystals accompanying by the formation of loose gold nanoparticles that gradually take a faceting. The results of these studies can be useful for solution of problems of designing multicomponent metallic materials with an evolution prediction of their structure–phase transformations under the service conditions.

中文翻译：

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二元Pb-Au体系的固相低温演化：通过与金属间化合物的接触相互作用，通过解构成新的多元素态

摘要

本文介绍了在室温和低温下进行的Au-Pb金属系统固相转变的长期实验结果。发现铅与金之间的固相接触相互作用导致形成Pb + AuPb ₃共析物。传质和相形成是由于铅沿渗滤通道挤出，而渗滤通道是金的亚结构破坏的结果。在接触金属的边界处没有反应层形成。基于金属间化合物AuPb ₃的固溶体的分解通过将材料分解为纳米颗粒，杂质原子从块体到边界的置换，固溶体中分离出的组分的整合和有序化等过程而发生。AuPb ₃金属间化合物的分解导致AuPb ₂的形成和可变组成的相，进而导致纯组分Au + Pb。分解发生在铅晶体快速生长的阶段，伴随着逐渐形成刻面的疏松金纳米颗粒的形成。这些研究的结果对于解决多组分金属材料在使用条件下其结构-相变的演化预测的设计很有用。