Adding alloying elements to increase precipitation is a common method to strengthen aluminum (Al) alloys, but an excessively high alloying element content causes segregation and a reduction in plasticity. In this work, the tradeoff between alloying element content and segregation was explored along with the simultaneous increase in precipitation and dislocation density under the action of trace TiB₂+TiC particles with the aim of giving a full play to the strengthening effect of dislocation and precipitation and maximizing the strength and toughness of the alloy. The cast Al–Zn–Mg–Cu alloys contained various alloying elements (Zn, Mg), and the alloys were reinforced with 0.5 wt% TiB₂+TiC particles via in-situ reaction in the Al melt. The TiB₂+TiC particles blocked the diffusion of the alloying elements and inhibited segregation, promoting solution of alloying elements and yielding dispersed and finer precipitates after solution and aging. Meanwhile, owing to the difference in the thermal expansion coefficients of the matrix and particles, the dislocation density of the alloy doubled. Therefore, the yield strength, elongation, and the product of the tensile strength and elongation of the Al-6.60Zn-3.15Mg-1.60Cu alloy with particles reinforcement were 562 MPa, 4.5%, and 3163 MPa·%, respectively, representing increases of 31.6%, 108.9%, and 186.0%, respectively, compared with the cast 7075 alloy. This study is significant for the successful preparation of high-strength and high-toughness cast aluminum alloys with high alloying-element content.

添加合金元素以增加沉淀是强化铝（Al）合金的常用方法，但过高的合金元素含量会导致偏析和塑性降低。_{本工作探索了在微量TiB 2} +TiC颗粒作用下合金元素含量与偏析以及析出和位错密度同时增加的权衡，旨在充分发挥位错和析出的强化作用。并最大限度地提高合金的强度和韧性。铸造的 Al-Zn-Mg-Cu 合金含有各种合金元素（Zn、Mg），合金通过在 Al 熔体中的原位反应用 0.5 wt% TiB _{2 +TiC 颗粒增强。}TiB ₂+TiC颗粒阻碍了合金元素的扩散，抑制了偏析，促进了合金元素的固溶，固溶和时效后析出物分散更细。同时，由于基体和颗粒的热膨胀系数不同，合金的位错密度增加了一倍。因此，颗粒增强的 Al-6.60Zn-3.15Mg-1.60Cu 合金的屈服强度、伸长率和抗拉强度与伸长率的乘积分别为 562 MPa、4.5% 和 3163 MPa·%，代表着增加与铸造 7075 合金相比，分别为 31.6%、108.9% 和 186.0%。该研究对成功制备高合金元素含量的高强高韧铸造铝合金具有重要意义。