深冷处理对非平衡凝固Al-Sc-Zr合金时效析出行为的影响  

Effect of cryogenic treatment on aging precipitation behavior of non-equilibrium solidified Al-Sc-Zr alloy

作　　者：宋雨琦 杨伟 彭玉炜 彭聪 徐翩 SONG Yu-qi;YANG Wei;PENG Yu-wei;PENG Cong;XU Pian(National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]南昌航空大学轻合金加工科学与技术国防重点学科实验室,江西南昌330063

出　　处：《材料热处理学报》2025年第3期51-59,共9页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(52061032,52261014)。

摘　　要：采用真空感应熔炼与铜模喷铸相结合,制备了快冷Al-0.3Sc-0.3Zr合金,研究了深冷处理对非平衡凝固合金时效析出行为的影响。结果表明:快冷合金的凝固组织为具有均匀细晶形貌的过饱和固溶体,深冷处理可以显著提高非平衡凝固合金中的位错数量,促进蜷线位错形成。经350℃时效15 min后,快冷合金的原始高固溶组织开始发生失稳,析出Al_(3)(Sc,Zr)纳米粒子。深冷处理引起的位错增殖效应能够进一步加快时效过程中析出相的连续析出。随时效时间延长至120 min,快冷及深冷处理合金中可以获得高密度的纳米析出相。由于析出相与基体保持良好共格关系,析出强化效应显著,时效120 min后合金的显微硬度高达71.74 HV0.2,相比原始快冷合金(32.31 HV0.2)提升了122%。Rapidly quenched Al-0.3Sc-0.3Zr alloy was prepared by combining vacuum induction melting with copper mold spraying casting,and the effect of cryogenic treatment on aging precipitation behavior of non-equilibrium solidified alloy was studied.The results show that the solidification structure of the rapidly quenched alloy is a supersaturated solid solution with uniform refined grain morphology,and the cryogenic treatment can significantly increase the number of dislocations in the non-equilibrium solidified alloy and promote the formation of helical dislocations.After aging at 350℃for 15 min,the original supersaturated solid solution microstructure of the rapidly quenched alloy begins to become unstable,and Al_(3)(Sc,Zr)nanoparticles are precipitated.The dislocation proliferation effect caused by cryogenic treatment can further accelerate the continuous precipitation of precipitates during the aging.As the aging time is increased to 120 min,high-density nano precipitates can be obtained in the rapidly quenched and cryogenic treated alloy.Due to the excellent coherent relationship between the precipitated phase and the matrix,the precipitation strengthening effect is significant.After 120 min of aging,the microhardness of the alloy reaches 71.74 HV0.2,which is 122%higher than the original rapidly quenched alloy(32.31 HV0.2).

关 键 词：非平衡凝固 深冷处理 时效析出 显微硬度 

分 类 号：TG146.2[一般工业技术—材料科学与工程]