摘要
结晶器是钢厂连铸设备中最关键的部件,结晶器铜板质量直接影响连铸坯表面质量、连铸机作业率和连铸成本。结晶器铜板在使用过程中存在边缘磨损、宽面热裂纹、窄面收缩、腐蚀等问题。目前,对结晶器铜板研究的重点是采用合适的表面处理技术在铜板表面镀覆一种或几种材料,以获得特殊功能表面,在保证其导热性受镀层影响不大的情况下,获得与基体结合牢固、耐磨性好、抗热腐蚀性强的各种镀层,以改善铜板的表面性能、延长其使用寿命、提高连铸坯质量,从而达到降低浇铸吨钢成本的目的。高速连铸的发展对结晶器表面性能提出了更高的要求,电镀、化学镀、热喷涂和激光熔覆等表面改性技术在连铸结晶器上的应用可以提高铜板表面的耐腐蚀、耐磨损等问题。结晶器铜板镀层的发展先后经过Cr镀层、Ni镀层、Ni?Fe镀层、Ni?Co(Co?Ni)镀层,其中,Co?Ni合金镀层的高温硬度较高、热稳定性好、抗电化学腐蚀性能强,是结晶器铜板较理想的镀层,但Co成本高,硬度较高时镀层应力大,抗热交变性能差。因此,近年来研究者又不断应用新工艺和新材料开发不同的涂镀层以进一步提高结晶器铜板的表面性能。从合金镀层到复合镀层,从热喷涂层到激光熔覆涂层,涂、镀层的硬度和耐磨性得到进一步提高。涂、镀层主要以Ni、Co为基相,Si、Cr、Zr、W、P是常见硬质相,Al2O3、碳化物、硼化物等作为陶瓷相来增强涂、镀层的耐磨性。纳米材料可以减小涂层的晶粒尺寸,其在增强涂层的致密性、改善涂层的耐磨性能及导热性等方面表现出独特的优势,成为开发新型结晶器表面涂层材料的热点。耐磨、导热性好的纳米级陶瓷颗粒应用于结晶器表面是优化现有涂、镀层性能的重要举措,采用多层结构的涂、镀层有利于提高涂、镀层与基体的结合强度。此外,在结晶器不同部位
The mould is the most critical component in the continuous casting machine in steelmaking plant. The quality of the mould copper plate directly affects the surface quality of the continuous casting slab, the operating rate and cost of continuous casting production. In the production, the mould copper plate mainly has problems of edge wear, wide surface hot crack, narrow surface shrinkage, corrosion. At present, the focus of research on mould copper plates is to adopt a suitable surface treatment technique to electroplate one or more materials on the surface of the copper plate to obtain a special functional surface. When the thermal conductivity of the mould is required not to be affected by the coatings, various coa-tings with strong bonding with the substrate, good wear resistance and strong thermal corrosion resistance are obtained to improve the surface properties of the copper plate, prolong the service life and improve the quality of the continuous casting slab, which leads to achieving the purpose of reducing the cost of casting steel.The development of high-speed continuous casting imposes higher requirements on the surface properties of the mould. Surface modification techniques such as electroplating, electroless plating, thermal spraying and laser cladding can be used to solve the problems of corrosion resistance and wear resistance of mould copper plate. The coatings of the mould copper plate were developed by Cr plating, Ni plating, Ni-Fe plating and Ni-Co (Co-Ni) coating. Co-Ni alloy coatings have high temperature hardness, good thermal stability and strong electrochemical corrosion resistance, which are ideal copper plate coatings for the mould copper plate, but the cost of Co is high, the plating stress is high when the hardness is high, and the heat exchange resistance is poor. Therefore, researchers have continuously applied new processes and materials to develop different coatings for further improving the surface properties of the mould copper plate in recent years. Coating materials change fr
作者
刘健健
朱诚意
李光强
LIU Jianjian;ZHU Chengyi;LI Guangqiang(The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2019年第17期2831-2838,共8页
Materials Reports
关键词
结晶器涂层
电镀
热喷涂
激光熔覆
性能
continuous casting mould coatings
electroplating
thermal spraying
laser cladding
properties
