Two-stage aging treatment to accelerate aging kinetics without impairing strength in B_4C/7A04Al composite  

作　　者：CHEN YunTao MA GuoNan ZHU ShiZe WANG Dong XIAO BoLv MA ZongYi 

机构地区：[1]Shi-Changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China [2]School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China [3]Centre of Excellence for Advanced Materials,Dongguan 523808,China

出　　处：《Science China(Technological Sciences)》2024年第8期2485-2492,共8页中国科学（技术科学英文版）

基　　金：supported by the National Key R&D Program of China (Grant No. 2022YFB3707405);the National Natural Science Foundation of China (Grant Nos. U22A20114 and 52301200);the Guangdong Basic and Applied Basic Research Foundation (Grant No. 2021A1515110525);the Project Funded by China Postdoctoral Science Foundation (Grant No. 2023M733573);the Natural Science Foundation of Liaoning Province (Grant No. 2023-BS-020);the Liaoning Revitalization Talents Program (Grant No. XLYC2007009)。

摘　　要：Aging treatments are the key process to obtain satisfactory strength for 7xxxAl alloys and their composites. However, traditional single-stage(SS) aging is time-consuming to reach a peak strength condition. In this study, an efficient 120℃ + 160℃ two-stage(TS) aging treatment was proposed on a B_4C/7A04Al composite fabricated via powder metallurgy(PM) technology, which could acquire similar peak-aging strength but only took about 15% of the time compared to traditional 120℃ SS aging. The evolution of precipitation during the TS aging was investigated, as well as those of the 7A04Al alloys for comparison. In the second stage aging process, the higher aging temperature accelerated the nucleation of η′ phases inside the grains and thus increased the density of precipitates. Moreover, the short aging time limited the coarsening of precipitates and the broadening of precipitatefree zones. The above factors were beneficial for quickly obtaining satisfactory precipitation strengthening effects. The B_4C/7A04Al composite exhibited slower aging kinetics than the 7A04Al alloy in the TS aging. Mg elements consumption by the chemical reaction between B impurities introduced by B_4C particles and the Al matrix was considered to potentially retard the aging kinetics of the B_4C/7A04Al composite. Nevertheless, the precipitation sequence was not affected.

关 键 词：aluminum matrix composites aging treatment powder metallurgy mechanical properties PRECIPITATION 

分 类 号：TB333[一般工业技术—材料科学与工程] TG156.92[金属学及工艺—热处理]