高级检索

    重型燃机用650 ℃级特大型GH4169高温合金透平盘制备关键技术

    Key Manufacturing Technologies for a 650 ℃-Class Ultra- large GH4169 Superalloy Turbine Disk for Heavy-duty Gas Turbines

    • 摘要: 为满足重型燃机对高承温、大尺寸透平盘的性能需求,针对超大尺寸GH4169高温合金透平盘制备过程中(冶炼、锻造及热处理)工序复杂、风险集中的问题开展了关键技术研究。以GH4169合金超大尺寸透平盘为研究对象,系统分析了真空感应熔炼(VIM)、真空自耗重熔(VAR)、去应力退火、均匀化,以及开坯和模锻过程中缩孔缺陷、元素偏析、有害相分布、组织演变与开裂损伤等关键问题。主要采用有限元模拟结合二次开发、热力学与动力学计算等方法,建立了电极锭凝固过程中缩孔缺陷与安全脱模时间的预测模型、VAR过程中铸锭元素偏析与Laves相分布预测方法、去应力退火损伤模型与应力松弛模型,以及基于Laves相回溶和Nb元素扩散的均匀化工艺设计模型,构建了组织控制-损伤控制-载荷控制相耦合的集成式锻造控制技术。结果表明:所提出的全流程控制技术可有效降低制备风险、优化盘锻件组织,为超大尺寸高温合金关键部件的制造提供了重要技术支撑,通过该技术成功制备出目前最大的直径2 440 mm级特大型GH4169合金透平盘。

       

      Abstract: To meet performance requirements of heavy-duty gas turbines for turbine disks with high temperature capability and large dimensions, a key technology study was conducted to address the high complexity and concentrated risks associated with melting, heat treatment, and forging during the fabrication of ultra-large GH4169 superalloy turbine disks. Taking a 650 ℃-class φ2 440 mm GH4169 superalloy turbine disk as the research object, key issues including shrinkage porosity, elemental segregation, harmful phase distribution, microstructural evolution, and cracking damage during vacuum induction melting (VIM), vacuum arc remelting (VAR), stress-relief annealing, homogenization, cogging, and die forging were systematically investigated. By using finite element simulation combined with secondary development, thermodynamic and kinetic modeling, and other methods, the following models and technologies were developed: a prediction model for shrinkage porosity and safe demolding during electrode ingot solidification; a prediction method for element segregation and Laves phase distribution in the VAR process; a stress relief annealing damage model and a stress relaxation model; a homogenization process design model based on Laves phase dissolution and Nb diffusion; and an integrated forging control technology that couples microstructure control, damage control, and load control. The results show that the proposed full-process control strategy can effectively reduce manufacturing risks and optimize the microstructure of disk forgings, providing important technical support for the manufacturing of key components of ultra-large-sized high-temperature alloys. By using this technology, the largest φ2 440 mm super-large GH4169 alloy turbine disk has been successfully fabricated.KG)

       

    /

    返回文章
    返回