Effect of Different Laser Energy Nitriding on the Fretting Wear Performance of Zr Alloy  

不同激光能量氮化对锆合金微动磨损性能的影响

作　　者：NING Chuangming TANG Guocan YU Shijia ZHOU Junbo REN Quanyao ZENG Bing CAI Zhenbing 宁闯明;唐国灿;余施佳;周俊波;任全耀;曾兵;蔡振兵(西南交通大学摩擦学研究所材料先进技术重点实验室,四川成都610031;成都理工大学机电工程学院,四川成都610031;中国核动力研究设计院核反应堆系统设计技术重点实验室,四川成都610213)

机构地区：[1]Key Laboratory of Advanced Technologies of Materials,Tribology Research Institute,Southwest Jiaotong University,Sichuan Chengdu 610031,China [2]School of Mechanical and Electrical Engineering,Chengdu University of Technology,Sichuan Chengdu 610031,China [3]Science and Technology on Reactor System Design Technology Laboratory,Nuclear Power Institute of China,Sichuan Chengdu 610213,China

出　　处：《摩擦学学报（中英文）》2024年第9期1306-1321,共16页Tribology

基　　金：国家重点研发计划项目(2022YFB3401901,2022YFB3401902);四川省科技项目(2022ZYD0029,2022JDJQ0019)资助.

摘　　要：The zirconium(Zr)alloy fuel cladding is one of the key structural components of a nuclear reactor and the first and most important line of defense for accommodating fission products.During the operation of nuclear reactors,Zr alloy fuel cladding is subjected to extreme harsh environments,such as high temperature,high pressure and high flow rate for a long period of time.The wear and corrosion resistance of Zr alloys is important for the safe operation of nuclear reactors.Surface modification can effectively improve the corrosion and wear resistance of fuel cladding.Compared with coating technology,nitriding technology does not have problems for bonding between the coating and the substrate.Current research on surface nitriding of Zr alloys mainly focuses on plasma nitriding and ion implantation techniques.Research on laser nitriding of Zr alloy surfaces and their fretting wear characteristics is scarce.In this study,the surface of Zr alloy was treated with laser nitriding at different laser energies.The microstructure of Zr alloy treated with different laser energies and its fretting wear performance were studied.The results showed that after nitriding with different laser energies,the surface of the Zr alloy showed a typical molten state after melting,vaporizing and cooling under the thermal effect of the laser,and this state was more obvious with the increase of the laser energy.At the same time,doping of N atoms and formation of the ZrN phase led to different cooling rates in the molten zone that produced large tensile stresses after cooling.This led to cracks on the surface of Zr alloys after laser nitriding at different energies,and the crack density increased with increasing laser energy.This also led to an increase in the surface roughness of the Zr alloy with increasing laser energy after laser nitriding treatment.Due to the presence of water in the industrial nitrogen,nitrides were generated on the surface of the sample along with some oxides.When the laser energy was 100 mJ,there was no ZrN generation,a为了提高锆合金的耐磨损性能,采用脉冲激光氮化技术对锆合金表面进行激光氮化处理.采用自主搭建的微动磨损试验机,研究了氮化处理后锆合金的微动磨损性能,利用X射线衍射、扫描电子显微镜和能谱仪等研究氮化处理后物相组成、表面微观形貌和元素分布等.结果表明:在不同激光能量氮化后,样品表面在激光热效应的作用下呈现出熔融状,并且熔融状结构随着激光能量的增加而变得更加明显;当激光能量为100 mJ时,N主要以扩散层的形式存在于Zr合金基体内部;当能量达到200 mJ及以上时,样品表面出现ZrN峰;与锆合金的空白基体相比,硬度提高了37.5%,激光氮化处理后Zr合金的微动磨损机制发生转变;未处理锆合金的磨损机制以分层剥落磨损为主,同时伴有氧化磨损和磨粒磨损;激光氮化处理后分层和剥落现象随着激光能量的增加而减少,磨损机制转变为以磨粒磨损为主,同时伴有氧化磨损和分层剥落;与未处理的锆合金相比,400 mJ激光氮化试样的磨损量减少了46.5%.

关 键 词：zirconium alloy fretting wear laser nitriding DELAMINATION laser energy 

分 类 号：TH117.1[机械工程—机械设计及理论] TL34[核科学技术—核技术及应用]