Investigation of oxidation and creep resistance of nickel-based alloy with superalloy hardfacing and thermal barrier coating

高温合金堆焊和热障涂层镍基合金的氧化和抗蠕变性能研究

• 批准号: 500913-2016
• 负责人: Liu, Rong
• 金额: $ 2.19万
• 依托单位: Carleton University
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=696315
• 关键词: Investigation; oxidation; creep; resistance; nickel

Advanced ultra supercritical (A USC) technology allows the steam temperature raised to 700 degree C in order to increase the efficiency of coalfired power generation and reduce its CO2 emission. While the high-Cr steel used for A-USC can withstand temperatures around 600 degree C, this move to higher temperatures requires the adoption of high performance materials such as Ni based alloys. For various valves operating in boiler, pipework and steam turbines of A-USC power generation plants, Inconel 740 and Haynes 282 have been selected for the body or base materials. To enhance the surface wear/erosion resistance, theses alloys are usually coated with Stellite alloy (Stellite 6) hardfacing. However, it has been found in recent years that Stellite 6 hardfacing degrades in the A-USC conditions and fails in service after a period of time. As a result, there is a strong demand from the valve industry, for example, Velan Inc., for an effective hardfacing material which can sustain the high temperature while they are resistant to wear and erosion. The proposed research attempts to apply a newly developed high performance Tribaloy alloy T-400C on Inconel 740 or Haynes 282 surface via plasma transferred arc (PTA) welding or laser cladding. The hardfacing specimens will be investigated under oxidation and creep tests. On the other hand, in order to reduce the temperature that directly acts on the Ni based alloy, thermal barrier coating (TBC) will be applied on Inconel 740 or Haynes 282; the coating system consists of a metallic bond coat and a ceramic topcoat composed of yttria-stabilized zirconia (YSZ). The oxidation and creep resistance of the coating specimens will be investigated at high temperatures between 650 and 850 degree C. Long-term creep test takes too long time and is impossible to be implemented in laboratory. Therefore a deformation mechanism based creep model for these coating/substrate systems will be developed to depict their short-term creep behaviour and meanwhile predict their long term creep resistance. The outcomes of this research will help reduce the costs of materials and equipment maintenance of the coal-fired power generation industry, with improving the efficiency of power generation technologies.

高级超临界（USC）技术使蒸汽温度升至700摄氏度，以提高煤炭发电的效率并减少其CO2发射。虽然用于A-USC的高CR钢可以承受600摄氏度左右的温度，但此移动到更高的温度需要采用高性能材料，例如基于NI的合金。对于在A-USC发电厂的锅炉，管道和蒸汽涡轮机中运行的各种阀门，已选择Inconel 740和Haynes 282用于车身或基本材料。为了增强表面磨损/侵蚀性，这些合金通常涂有星状合金（Stellite 6）硬化。但是，近年来已经发现，在A-USC条件下，Stellite 6的6个硬化降解，并且在一段时间后服役。结果，阀门行业的需求很大，例如Velan Inc.，是一种有效的固定材料，该材料可以在耐磨损和侵蚀性的同时维持高温。拟议的研究试图通过等离子体转移ARC（PTA）焊接或激光覆层在Inconel 740或Haynes 282表面上应用新开发的高性能Tribaloy合金T-400C。将在氧化和蠕变测试中研究硬膜标本。另一方面，为了降低直接作用于NI基合金的温度，将在Inconel 740或Haynes 282上应用热屏障涂层（TBC）；涂料系统由金属键涂层和由Yttria稳定的氧化锆（YSZ）组成的陶瓷面漆组成。涂料样品的氧化和蠕变耐药性将在650至850摄氏度之间进行研究。长期蠕变测试需要太长时间，并且无法在实验室中实施。因此，将开发基于变形机制的基于变形机制的蠕变模型，以描述其短期蠕变行为，同时预测其长期蠕变抗性。这项研究的结果将有助于降低燃煤发电行业的材料和设备维护成本，从而提高发电技术的效率。