Brazeability of similar hybrid joint compounds consisting of additively manufactured and conventional material grades

由增材制造和传统材料等级组成的类似混合接头化合物的可钎焊性

• 批准号: 407147480
• 负责人: Professor Dr.-Ing. Wolfgang Tillmann
• 金额: --
• 依托单位: Lehrstuhl für Werkstofftechnologie (LWT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407147480?language=en
• 关键词: Brazeability; similar; hybrid; joint; compounds

Selective-Laser-Melting (SLM) is a metal-powder-based manufacturing process that offers the best possible design options for the production of highly complex components. Until today, generating a SLM part on a simple geometrical, conventionally produced component requires such components to be segmented, brazed and tempered prior to realizing a hybrid joint compound. The disadvantages of this procedure are mainly based on the fact that the SLM part contains high residual stresses and has a completely different material structure in the generated state. Therefore, these compounds offer wholly dissimilar mechanical-technological properties. Furthermore, technically efficient SLM components require a subsequent heat treatment which extends the already complex production chain by another process step.Selective laser melting as well as a combined brazing/heat treatment processes offer a great potential to combine the respective advantages into an efficient production chain. As proven in preliminary tests, the residual porosity and oxide inclusions affect the brazing quality and the joint strength significantly, although the SLM materials had a density higher than 99.8 vol.-%. This research project will systematically generate fundamental knowledge to braze similar composite and hybrid composites of conventional and SLM material grades for austenitic stainless steel 316L (X2CrNiMo17-12-2) and nickel maraging tool steel 18Ni300 (X3NiCoMoTi18-9-5). Furthermore, the brazed joints will be benchmarked to appropriate composites which are only manufactured by selective laser melting. Additionally, the joints will be heat-treated to equalize the microstructure and minimize residual stresses. The overall objective is to establish a suitable process chain to produce similar hybrid composites of SLM and conventional materials, which is based on characteristic values of the mechanical joint properties. In detail, the focus of the research project is mainly the investigation of the brazing process using these material grades. The established brazing processes for conventional composites are transferred to these composites and analyzed with respect to the wetting and flow behavior, the joint strength, with a strong focus on the influence of pores and oxides within the SLM material to the brazing quality. In addition, gas phase etching followed by nickel plating of the joining surfaces will be examined for the brazing samples. These processes will remove the oxides and close the open porosity, thus enhancing the brazing quality and the joint strength significantly.

选择性激光熔化 (SLM) 是一种基于金属粉末的制造工艺，可为高度复杂部件的生产提供最佳的设计选项。直到今天，在简单的几何形状、传统生产的组件上生成 SLM 零件需要在实现混合接头化合物之前对此类组件进行分段、钎焊和回火。该过程的缺点主要是因为SLM零件含有高残余应力，并且在生成状态下具有完全不同的材料结构。因此，这些化合物提供完全不同的机械技术性能。此外，技术上高效的 SLM 部件需要后续热处理，从而通过另一个工艺步骤扩展了本已复杂的生产链。选择性激光熔化以及组合钎焊/热处理工艺提供了将各自优势结合到高效生产链中的巨大潜力。初步测试证明，尽管 SLM 材料的密度高于 99.8 vol.-%，但残余孔隙率和氧化物夹杂物仍显着影响钎焊质量和接头强度。该研究项目将系统地生成基础知识，以钎焊奥氏体不锈钢 316L (X2CrNiMo17-12-2) 和镍马氏体时效工具钢 18Ni300 (X3NiCoMoTi18-9-5) 的传统和 SLM 材料等级的类似复合材料和混合复合材料。此外，钎焊接头将以仅通过选择性激光熔化制造的适当复合材料为基准。此外，接头将经过热处理，以均衡微观结构并最大限度地减少残余应力。总体目标是建立一个合适的工艺链来生产类似的 SLM 和传统材料的混合复合材料，这是基于机械接头性能的特征值。具体来说，该研究项目的重点主要是研究使用这些材料等级的钎焊工艺。将传统复合材料的既定钎焊工艺转移到这些复合材料上，并分析润湿和流动行为、接头强度，重点关注 SLM 材料内的孔隙和氧化物对钎焊质量的影响。此外，还将检查钎焊样品的气相蚀刻，然后对连接表面进行镀镍。这些工艺将去除氧化物并封闭开孔，从而显着提高钎焊质量和接头强度。