Nam, Seungjin Chang, Kunok Lee, Woonki Kim, Moon J. Hwang, Jun Yeon Choi, Hyunjoo 2024-01-19T23:32:56Z 2024-01-19T23:32:56Z 2021-09-03 2018-01-25 2045-2322 https://pubs.kist.re.kr/handle/201004/121795 While nanocrystalline (NC) metals exhibit superior strength to conventional microcrystalline metals, their thermal instability has hampered their application at high temperatures. Herein, two-dimensional (2D) boron nitride nanosheets (BNNS) are proposed as reinforcement to enhance the strength as well as the thermal stability of NC Al. The strength of pure Al was increased from 80 to 468 MPa by refining its grains from similar to 600 to similar to 40 nm, and it was further enhanced to 685 MPa by incorporating 2 vol% of BNNS. Moreover, the small amount of BNNS was found to effectively suppress grain growth of NC Al at 580 degrees C (similar to 0.9 T-m, where T-m is the melting point of Al), which prevented a strength drop at high temperature. Finally, the Zener pinning model in conjunction with phase-field simulations was utilized to qualitatively analyze the effect of the BNNS on the grain boundary pinning as a function of volume, shape, and orientation of the reinforcement. The model demonstrated that the pinning force of 2D reinforcements is much higher than that of spherical particles. Hence, 2D BNNS offer the possibility of developing Al-matrix nanocomposites for high-temperature structural applications. English NATURE PUBLISHING GROUP BORON-NITRIDE NANOSHEETS THERMAL-STABILITY MECHANICAL-PROPERTIES BOUNDARY SEGREGATION COMPUTER-SIMULATION COPPER-ALLOYS HIGH-PRESSURE STRENGTH NANOTUBES MICROSTRUCTURE Structural effect of two-dimensional BNNS on grain growth suppressing behaviors in Al-matrix nanocomposites Article 10.1038/s41598-018-20150-5 1 SCIENTIFIC REPORTS, v.8 SCIENTIFIC REPORTS 8 scie scopus 000423422700033 2-s2.0-85041030712 Multidisciplinary Sciences Science & Technology - Other Topics Article BORON-NITRIDE NANOSHEETS THERMAL-STABILITY MECHANICAL-PROPERTIES BOUNDARY SEGREGATION COMPUTER-SIMULATION COPPER-ALLOYS HIGH-PRESSURE STRENGTH NANOTUBES MICROSTRUCTURE BNNT Al matrix nanocomposite Grain growth TEM