The use of Pb-containing solders in electronic products has been restricted due to their harm to both human health and the environment. Although the Sn–37Pb solder has been well replaced by Sn–3.0Ag–0.5Cu or other Pb-free solders, there is no drop in replacement for high-temperature Pb-free solders. In this study, the microstructure and high-temperature tensile properties of the Zn–25Sn–x(0.1–0.2)Cu–y(0.01–0.02)Ti high-temperature Pb-free solders were investigated. The design of the moderate alloy composition prevented undesirable Cu- and Ti-containing intermetallic compound formation that may cause alloy embrittlement. The solders exhibit superior tensile strength and competitive elongation compared with the conventional high-Pb solders and the other potential candidates. The Zn–25Sn–xCu–yTi solders can be strengthened in terms of the tensile strength enhancement without a loss of ductility under both room-temperature and high-temperature testing conditions. The minor Cu and Ti elements served as heterogeneous nucleation sites for inducing the microstructure refinement of the primary (Zn) phase. The Cu-in-Zn solid solution phenomenon as well as the formation of deformation twins during the high-temperature tensile test also contributed to the superior tensile properties of the designed alloys.

由于含铅焊料对人体健康和环境均有害，因此限制了其在电子产品中的使用。尽管Sn-37Pb焊料已被Sn-3.0Ag-0.5Cu或其他无铅焊料很好地替代，但高温无铅焊料的替代量却没有下降。在这项研究中，Zn–25Sn– x（0.1–0.2）Cu– y的组织和高温拉伸性能研究了（0.01–0.02）Ti高温无铅焊料。中度合金成分的设计可防止形成可能导致合金脆化的不良的含Cu和Ti的金属间化合物。与传统的高铅焊料和其他潜在的候选焊料相比，该焊料具有卓越的拉伸强度和竞争性伸长率。Zn–25Sn– x Cu– y在室温和高温测试条件下，可以提高钛合金的抗拉强度，而又不会降低延展性。微量的Cu和Ti元素用作异质形核位点，以诱导初级（Zn）相的微观结构细化。铜-锌-锌固溶现象以及高温拉伸试验过程中形变孪晶的形成也有助于所设计合金的优异拉伸性能。