ABSTRACT Deformation bands, especially shear bands were intentionally formed in supersaturated Cu-4 at.% Ti alloy by groove-rolling with 75% area reduction. Cold deformation prior to the ageing process changed the precipitation behaviour of the alloy. The deformed structure with shear bands was maintained, without showing recovery and recrystallisation, even after prolonged ageing at 450°C for more than one day. The thermally stable shear bands act as nucleation initiation sites and prevent the expansion of discontinuous cellular precipitates. The hardness reached a value of 305 Hv and an electrical conductivity of 15% IACS (IACS = International Annealed Copper Standard. 100% IACS is defined as the conductivity corresponding to a volume resistivity at 20°C of 17.241 nΩ), compared to 283 Hv and 13% IACS for conventional solid-solutioned and peak-hardened alloy. In addition, the ageing time to reach the highest hardness was shortened from 720 to 180 min at 450°C.

中文翻译：

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在 Cu-4 at.% Ti 合金时效前通过变形加速异质成核以提高硬度和电导率

摘要 变形带，尤其是剪切带是在过饱和的 Cu-4 at.% Ti 合金中通过槽轧制成的，面积减少了 75%。时效过程之前的冷变形改变了合金的析出行为。即使在 450°C 下长时间老化超过一天后，仍保持具有剪切带的变形结构，没有显示恢复和再结晶。热稳定剪切带作为成核起始位点并防止不连续细胞沉淀物的膨胀。硬度达到305 Hv值，电导率15% IACS（IACS = International Annealed Copper Standard。100% IACS定义为20°C下体积电阻率对应的电导率为17.241 nΩ），与传统固溶和峰值硬化合金的 283 Hv 和 13% IACS 相比。此外，在 450°C 下达到最高硬度的时效时间从 720 分钟缩短到 180 分钟。