High-entropy alloys(HEAs)exhibit extraordinary physical properties such as superior strength-to-weight ratios and enhanced corrosion and oxidation resistance,making them potentially useful in energy storage and gener-...High-entropy alloys(HEAs)exhibit extraordinary physical properties such as superior strength-to-weight ratios and enhanced corrosion and oxidation resistance,making them potentially useful in energy storage and gener-ation industries.However,thermal and mechanical properties of HEAs with various compositions vary signifi-cantly.Furthermore,these properties have rarely been investigated simultaneously owing to material or instru-mentation limitations.Herein,we synthesize an HEA(AlCrNbSiTi)coating with a thickness of less than 2μm.We customize a frequency-domain photothermal testing system to characterize the thermal and mechanical proper-ties of the proposed coating with high accuracy.Owing to the large mixing enthalpy of the Al-Ti,Nb-Si,and Ti-Si pairs in the coating,its hardness and elastic modulus are 15.2 and 254.7 GPa,respectively,which are higher than those of previously reported HEAs.The thermal conductivity of the AlCrNbSiTi coating is characterized to be 2.90 W·m^(−1)·K^(−1),within the expected range and well explained by the free-electron consistency diversity and phonon scattering from the amorphous structure.Additionally,the coating exhibits adequate wear performance,with a wear rate of 5.4×10^(−8) mm^(3)·N^(−1)·m^(−1).This relatively low thermal conductivity,combined with extraordi-nary mechanical properties,makes the proposed material an excellent candidate as a protective coating material for nuclear reactor components which require high strength,irradiation resistance,and thermal protection.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.:52076156)Natural Sci-ence Foundation of Hubei Province(Grant No.:2021CFB120)+1 种基金Wuhan University Sino-Foreign Joint Scientific Research Project(Grant No.:WHUZZJJ202223)Fundamental Research Funds for Central Uni-versities(Grant No.:2042022kf1020).
文摘High-entropy alloys(HEAs)exhibit extraordinary physical properties such as superior strength-to-weight ratios and enhanced corrosion and oxidation resistance,making them potentially useful in energy storage and gener-ation industries.However,thermal and mechanical properties of HEAs with various compositions vary signifi-cantly.Furthermore,these properties have rarely been investigated simultaneously owing to material or instru-mentation limitations.Herein,we synthesize an HEA(AlCrNbSiTi)coating with a thickness of less than 2μm.We customize a frequency-domain photothermal testing system to characterize the thermal and mechanical proper-ties of the proposed coating with high accuracy.Owing to the large mixing enthalpy of the Al-Ti,Nb-Si,and Ti-Si pairs in the coating,its hardness and elastic modulus are 15.2 and 254.7 GPa,respectively,which are higher than those of previously reported HEAs.The thermal conductivity of the AlCrNbSiTi coating is characterized to be 2.90 W·m^(−1)·K^(−1),within the expected range and well explained by the free-electron consistency diversity and phonon scattering from the amorphous structure.Additionally,the coating exhibits adequate wear performance,with a wear rate of 5.4×10^(−8) mm^(3)·N^(−1)·m^(−1).This relatively low thermal conductivity,combined with extraordi-nary mechanical properties,makes the proposed material an excellent candidate as a protective coating material for nuclear reactor components which require high strength,irradiation resistance,and thermal protection.
