Ralls Alessandro M, Daroonparvar Mohammadreza, John Merbin, Sikdar Soumya, Menezes Pradeep L
Department of Mechanical Engineering, University of Nevada Reno, Reno, NV 89557, USA.
ASB Industries, Research and Development Department, Barberton, OH 44203, USA.
Materials (Basel). 2023 Mar 30;16(7):2765. doi: 10.3390/ma16072765.
Ni-based superalloys have been extensively employed in the aerospace field because of their excellent thermal and mechanical stabilities at high temperatures. With these advantages, many sought to study the influence of fusion-reliant additive manufacturing (AM) techniques for part fabrication/reparation. However, their fabrication presents many problems related to the melting and solidification defects from the feedstock material. Such defects consist of oxidation, inclusions, hot tearing, cracking, and elemental segregation. Consequentially, these defects created a need to discover an AM technique that can mitigate these disadvantages. The cold spray (CS) process is one additive technique that can mitigate these issues. This is largely due to its cost-effectiveness, low temperature, and fast and clean deposition process. However, its effectiveness for Ni-based superalloy fabrication and its structural performance has yet to be determined. This review aimed to fill this knowledge gap in two different ways. First, the advantages of CS technology for Ni-based superalloys compared with thermal-reliant AM techniques are briefly discussed. Second, the processing-structure-property relationships of these deposits are elucidated from microstructural, mechanical, and tribological (from low to high temperatures) perspectives. Considering the porous and brittle defects of CS coatings, a comprehensive review of the post-processing techniques for CS-fabricated Ni superalloys is also introduced. Based on this knowledge, the key structure-property mechanisms of CS Ni superalloys are elucidated with suggestions on how knowledge gaps in the field can be filled in the near future.
镍基高温合金因其在高温下具有出色的热稳定性和机械稳定性，已在航空航天领域得到广泛应用。凭借这些优势，许多人试图研究依赖熔合的增材制造（AM）技术对零件制造/修复的影响。然而，其制造过程存在许多与原料熔化和凝固缺陷相关的问题。这些缺陷包括氧化、夹杂物、热撕裂、裂纹和元素偏析。因此，这些缺陷促使人们需要找到一种能够减轻这些缺点的增材制造技术。冷喷涂（CS）工艺就是一种能够解决这些问题的增材制造技术。这主要归功于其成本效益高、温度低以及沉积过程快速且清洁。然而，其在镍基高温合金制造方面的有效性及其结构性能尚未确定。本综述旨在通过两种不同方式填补这一知识空白。首先，简要讨论了与依赖热的增材制造技术相比，冷喷涂技术用于镍基高温合金的优势。其次，从微观结构、力学和摩擦学（从低温到高温）角度阐明了这些沉积物的加工 - 结构 - 性能关系。考虑到冷喷涂涂层存在多孔和脆性缺陷，还介绍了对冷喷涂制造的镍基高温合金后处理技术的全面综述。基于这些知识，阐明了冷喷涂镍基高温合金关键的结构 - 性能机制，并就如何在不久的将来填补该领域的知识空白提出了建议。
