NiCoCrFeNb_(0.45)共晶高熵合金在水力机械中的抗空蚀性能研究  

Cavitation Resistance of NiCoCrFeNb_(0.45) Eutectic High Entropy Alloy for Hydraulic Machinery

作　　者：王凯[1] 李晨沛 卢金玲[1] 王振江 王维 WANG Kai;LI Chenpei;LU Jinling;WANG Zhenjiang;WANG Wei(State Key Laboratory of Eco-hydraulic in Northwest Arid Region,Xi'an University of Technology,Xi'an 710048,China;Science and Technology on Liquid Rocket Engine Laboratory,Xi'an Aerospace Propulsion Institute,Xi'an 710010,China)

机构地区：[1]西安理工大学西北旱区生态水利国家重点实验室,西安710048 [2]西安航天动力研究所液体火箭发动机技术重点实验室,西安710010

出　　处：《中国腐蚀与防护学报》2023年第5期1079-1086,共8页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(51879216,51906200和51906201);陕西省教育厅重点实验室科研计划项目(19JS045)。

摘　　要：构建了喷射式空蚀实验装置,开展了新型共晶高熵合金NiCoCrFeNb_(0.45)的抗空蚀性能测试,利用灰度共生矩阵和二值化图像方法,开发了基于图像智能识别的空蚀损伤新型表征方法,实现了空蚀分布形态的数字化分析和空蚀局部损伤的微观评估。结果表明:NiCoCrFeNb_(0.45)的空蚀损伤机制为空泡溃灭造成的形变坑以及加工硬化造成的疲劳裂纹;NiCoCrFeNb_(0.45)的双相共晶组织包含了高硬度的Laves相和高韧性的FCC相,实现了高硬度和高韧性的平衡,相比04Cr13Ni5Mo和45钢具有更优异的抗空蚀性能;利用灰度共生矩阵提取的空蚀图像标准差、能量值和熵值等特征参数表明NiCoCrFeNb_(0.45)空蚀损伤形态分布最为简单,空蚀程度最轻;图像二值化方法可获取材料表面大规模蚀坑群的分布规律,NiCoCrFeNb_(0.45)的空蚀率为8.1%,显著低于另两种材料。该研究为水力机械的空蚀损伤评估及材料防护提供了新的理论参考。The cavitation resistance of a new eutectic high entropy alloy NiCoCrFeNb_(0.45) was assessed via a home-made jet cavitation experimental device.While a new characterization method for cavitation damage,based on image intelligent recognition,was developed by using gray level co-occurrence matrix and binary image method.Therewith,the digital analysis of cavitation damage distribution and the microscopic assessment of local cavitation damage could be realized.The results show that the primary cavitation damage mechanism of NiCoCrFeNb_(0.45) is the deformable pits caused by repeated cavitation collapse,as well as the fatigue cracks induced by the work hardening.The dual-phase eutectic structure of NiCoCrFeNb_(0.45) is composed of Laves phase with high hardness and FCC phase with high toughness,which achieves the balance between high hardness and high toughness.As a result,NiCoCrFeNb_(0.45) has a superior cavitation damage resistance,compared with 04Cr13Ni5Mo and 45 steel.The characteristic parameters,such as standard deviation,energy value and entropy value of cavitation image,are extracted by gray level co-occurrence matrix,and these parameters show that the distribution of cavitation damage for NiCoCrFeNb_(0.45) is the simplest,and the degree of cavitation damage is the lowest.The image binarization method could help to obtain the regularity of distribution of large-scale pits on the material surface.The cavitation damage ratio of NiCoCrFeNb_(0.45) is 8.1%,which is significantly lower than that of the other two materials.This study provides a new reference for cavitation damage assessment and material protection for hydraulic machinery.

关 键 词：水力机械 抗空蚀材料 图像识别 共晶高熵合金 损伤评估 

分 类 号：TH312[机械工程—机械制造及自动化]