Luo Ying, Dong Yuanyuan, Xiao Cong, Wang Xiaotong, Peng Hang
School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu 610041, China.
Materials (Basel). 2022 Mar 17;15(6):2214. doi: 10.3390/ma15062214.
The impact wear property of hard coatings at elevated temperatures is of particular interest for applications in nuclear power plants. This study evaluated the impact wear behavior of two CrAlN/TiSiN coatings with and without sand. Alternately grown CrAlN and TiSiN films with modulation periods of 455 and 19 nm were formed in a columnar structure. The nanomultilayer shows better impact wear resistance than multilayer films with and without sand. The energy absorption rate has a similar trend to wear rate, leading to lower rebound velocity and peak impact force of the nanomultilayer compared with that of the multilayer. CrAlN/TiSiN coatings can protect the 308L substrate from oxidation. The dominant impact wear mechanism without sand is plastic deformation, and this wear region can be defined as the percussive zone. Peeling occurs on the multilayer surface without sand after 10 percussions, leading to rapid oxidation of the 308L substrate at 500 °C. Due to the abrasion effect, the wear rate of the sample with sand increases by an order of magnitude compared to the sample without sand. The wear scar of the sample with sand can be divided into the mixing zone and the sand-affected zone from inside to outside. Fe oxides are formed beyond the unbroken coating, which may be related to the outward diffusion of Fe.
高温下硬质涂层的冲击磨损性能在核电站应用中尤为重要。本研究评估了两种有砂和无砂CrAlN/TiSiN涂层的冲击磨损行为。调制周期为455和19 nm的交替生长CrAlN和TiSiN薄膜形成柱状结构。纳米多层膜比有砂和无砂的多层膜表现出更好的抗冲击磨损性能。能量吸收率与磨损率趋势相似，导致纳米多层膜的反弹速度和峰值冲击力低于多层膜。CrAlN/TiSiN涂层可保护308L基体免受氧化。无砂时的主要冲击磨损机制是塑性变形，该磨损区域可定义为冲击区。无砂多层膜表面在10次冲击后出现剥落，导致308L基体在500℃时快速氧化。由于磨蚀作用，有砂样品的磨损率比无砂样品增加了一个数量级。有砂样品的磨损疤痕从内到外可分为混合区和砂影响区。在未破损涂层之外形成了铁氧化物，这可能与铁的向外扩散有关。
