Goel Sneha, Bourreau Kévin, Olsson Jonas, Klement Uta, Joshi Shrikant
Department of Engineering Science, University West, Trollhättan 46186, Sweden.
Specialty Materials, University of Limoges, Limoges 87000, France.
Materials (Basel). 2020 Jan 23;13(3):536. doi: 10.3390/ma13030536.
Electron beam melting (EBM) is gaining rapid popularity for production of complex customized parts. For strategic applications involving materials like superalloys (e.g., Alloy 718), post-treatments including hot isostatic pressing (HIPing) to eliminate defects, and solutionizing and aging to achieve the desired phase constitution are often practiced. The present study specifically explores the ability of the combination of the above post-treatments to render the as-built defect content in EBM Alloy 718 irrelevant. Results show that HIPing can reduce defect content from as high as 17% in as-built samples (intentionally generated employing increased processing speeds in this illustrative proof-of-concept study) to <0.3%, with the small amount of remnant defects being mainly associated with oxide inclusions. The subsequent solution and aging treatments are also found to yield virtually identical phase distribution and hardness values in samples with vastly varying as-built defect contents. This can have considerable implications in contributing to minimizing elaborate process optimization efforts as well as slightly enhancing production speeds to promote industrialization of EBM for applications that demand the above post-treatments.
电子束熔炼（EBM）在生产复杂定制零件方面正迅速受到欢迎。对于涉及高温合金（如718合金）等材料的战略应用，通常会进行包括热等静压（HIPing）以消除缺陷，以及固溶处理和时效处理以实现所需相组成的后处理。本研究具体探讨了上述后处理组合使电子束熔炼718合金中原始缺陷含量变得无关紧要的能力。结果表明，热等静压可将原始样品中高达17%的缺陷含量（在本示例性概念验证研究中通过提高加工速度有意产生）降低至<0.3%，少量残余缺陷主要与氧化物夹杂有关。随后的固溶处理和时效处理还发现，在原始缺陷含量差异很大的样品中，能产生几乎相同的相分布和硬度值。这对于尽量减少精细的工艺优化工作以及略微提高生产速度以促进电子束熔炼在需要上述后处理的应用中的工业化具有重要意义。
