高炉风口小套防护覆层的界面调控机制与服役强化实践

The comprehensive metallurgical technology of high efficiency and long life blast furnace is one of the key breakthroughs of major metallurgical equipment technology. The tuyere small sleeve of blast furnace is the core part for blast furnace ironmaking. Effective protection and service intensification of tuyere sleeve are the bottlenecks to be solved in the comprehensive smelting technology of blast furnace. .This project aims at in-depth analysis of tuyere sleeve failure mechanism, the fabrication of a reliable protective coating on the surface of the tuyere small sleeve will be investigated. The key scientific issues of the interfacial connection mechanism and regulation of high-performance protective layer material will be focused on. We will use the inverse design system to design the protective material and structure of tuyere small sleeve by simulation of temperature field and stress field. The performance optimization matching of different cladding materials and the mechanism of coupling and controlling between layers will be studied systemically. A quasi-continuous gradient function composite protective coating will be prepared on the surface on the small sleeve. The difficult problem about reliable bonding between the protective layer and the sleeve substrate will be solved. A effective protection key technology and the process prototype of tuyere small sleeve will be constructed. The project aims to achieve the longevity of the tuyere small sleeve, reduce the heat loss of tuyere cooling and improve the air temperature, lay the theoretical and technical foundation for a stable and efficient operation of blast furnace. The implementation of the project will lay a theoretical and technical foundation for the energy saving and consumption reduction, stable and efficient operation of blast furnace ironmaking production.

高效节能长寿命高炉综合冶炼技术为冶金重大装备重点突破的技术之一。高炉风口小套是高炉炼铁生产的核心关键部件，风口小套的有效防护，服役强化是实现高炉综合冶炼技术突破亟待解决的瓶颈问题。.本项目拟在深入分析风口小套失效机理的基础上，从其表面制备可靠防护覆层出发，围绕高性能防护层材料和覆层界面连接机理及调控关键科学问题，采用逆设计系统思想，通过温度场和应力分布的模拟，优化设计风口小套表面防护层材料和结构，系统研究不同覆层材料的性能优化匹配、层间连接耦合调控机理，在小套本体上制备准连续梯度功能复合防护覆层，解决防护层与风口小套基体可靠接合的关键难点问题，构建对风口小套科学有效防护的关键技术和工艺原型。项目旨在通过高炉风口小套防护覆层结构优化，实现降低风口冷却热损失、提高风温，使用寿命强化的目的。项目的实施，必将为高炉炼铁生产节能降耗、稳定高效运行奠定理论和技术基础。

本项目在深入剖析风口小套失效机制的基础上，建立风口小套服役温度场和应力分布的有限元模型，设计和开发高性能防护覆层，揭示铜基表面防护覆层可靠连接机理及调控的关键科学问题，突破风口小套表面有效防护的关键技术，构建风口小套表面功能梯度防护层制备的工艺原型，实现高炉风口小套长寿化，为炼铁生产节能降耗、稳定高效运行提供技术支撑。通过四年的研究，顺利完成了预期目标，主要研究成果包括：1）系统剖析了失效风口小套，发现煤/焦磨损和渣铁熔损是其主要失效机制。2）建立了风口小套服役过程温度场、应力场分布有限元模型，明确了防护型风口小套表面覆层材料设计的边界条件。3）设计搭建了等离子-感应加热耦合和激光-感应加热耦合两套熔覆系统，开发了铜基表面高性能镍基、钴基、碳化物增强、合金-陶瓷防护涂层的制备工艺，揭示了异种材料界面结合规律及其可靠连接的调控机制。4）构建了防护型高炉风口小套表面涂层制备工艺技术原型，建立了1套千立方级高炉风口小套表面熔覆防护层的装置系统，完成了12个风口小套表面功能梯度防护层的熔覆制备，并在高炉中进行服役试验。通过本项目研究显著提升了风口小套表面硬度、耐磨性及抗渣铁熔损性能，有望大幅度延长其服役寿命。在本项目资助下，共发表学术论文48篇，其中SCI收录47篇；申请国家发明专利6项，授权国家发明专利2项；项目执行期间，项目组入选上海市重点创新团队，项目负责人获中国产学研合作创新成果奖（优秀奖）1次；培养出站博士后2人，培养毕业博士1名、毕业硕士8名，其中获得国家奖学金2人，校级优秀毕业生3人，获全国大学生冶金科技竞赛2人次；项目组成员获批国家优青1人次，晋升正高级和副高级职称各1人，获上海市超级博士激励计划3人次，获上海大学材料科学与工程学院优秀青年教师1人次。项目超额完成了预期任务指标。