在高频插拔与振动工况下,弹性后效的存在使得电连接器接触压力不稳定,从而导致传输性能和传输效率降低。本文对QBe2.0合金分别进行单级时效和双级时效处理,采用扫描电子显微镜、X射线衍射仪、透射电子显微镜和高频试验机等研究不同时效条件下QBe2.0合金的微观组织及弹性后效行为,并揭示其强化机制。结果表明：在240 ℃/150 min+290 ℃/180 min的双级时效条件下,QBe2.0合金的弹性后效性能最佳,弹性后效值为2.83%。相较于单级时效处理,该优化工艺有利于促进细小均匀的γ′析出相形成。这些析出相可以有效地钉扎位错,缩短位错自由段的长度,提高位错迁移的能量势垒,减小位错回弹的幅度和特征时间尺度,从而显著抑制弹性后效。该研究成果可为开发适用于高性能电连接器的弹性元件提供理论依据和实用工艺指导。
Under high-frequency insertion and extraction and vibrational conditions, the presence of elastic after-effect results in unstable contact stress of electrical connectors and consequently degrades transmission performance and transfer efficiency. In this work, QBe2.0 alloy was subjected to single and double stage aging treatments. The microstructure and elastic after-effect behavior of QBe2.0 alloy under different aging conditions were investigated using scanning electron microscope, X-ray diffractometer, transmission electron microscope, and high-frequency testing machine, and the underlying strengthening mechanism was elucidated. The results show that the elastic after-effect performance of QBe2.0 alloy is optimized under double-stage aging at 240 ℃/150 min+290 ℃/180 min, with an elastic after-effect value of 2.83%. Compared with single-stage aging, this optimized process promotes the formation of fine and homogeneous γ′ precipitates. These precipitates effectively pin dislocations, shorten the length of dislocation free segments, increase the energy barrier for dislocation migration, and reduce both the amplitude and characteristic time scale of dislocation rebound, thereby significantly suppressing elastic after-effect. This study provides theoretical foundations and practical process guidance for developing elastic components suitable for high-performance electrical connectors.
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