Metal binder jetting system for the entire additive process chain

适用于整个增材工艺链的金属粘合剂喷射系统

• 批准号: 460825330
• 金额: --
• 依托单位: Rheinisch-Westfälische Technische Hochschule Aachen
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2022
• 资助国家: 德国
• 起止时间: 2021-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/460825330?language=en
• 关键词: Metal; binder; jetting; system; entire

Direct-melting metal-based additive manufacturing (AM) processes such as laser powder bed fusion (LPBF) make it possible to produce geometrically complex components, such as topology-optimized grid structures, with high component density and geometric dimensional accuracy. However, low build-up rates and the associated high component costs prevent the broad industrial application, especially in cost-driven industrial areas such as the automotive sector. The necessary increase in productivity of AM can be addressed by the further development of indirect powder bed AM processes such as Metal Binder Jetting (MBJ) with significantly higher build-up rates.The layer-by-layer printing concept of the MBJ developed in the 1990s is comparable to the LPBF process in terms of process sequence. However, instead of a focused laser beam, the MBJ uses a multi-nozzle print head to selectively apply Binder micro-droplets to the powder bed. After the binder application, the powder bed is lowered one layer in the installation space and another layer is applied. The steps powder application, binder application, powder bed lowering are repeated until the component is completely assembled. After the printing process, the powder bed is cured, whereby the liquid components of the binder evaporate. The cured binder-polymer and metal powder form a solid green part, which allows the removal of the uninfiltrated powder. The green body is then sintered in a furnace near the melting temperature. During this process, the binder dissolves thermally. In addition to speed advantages, MBJ sintering offers further advantages over direct AM processes, e.g. in the processing of hard metals or alloys that are difficult to weld.Due to the recent entry of new, established industrial companies such as Hewlett Packard into the MBJ field, there is a clear development compared to the previous possibilities of the MBJ. However, the development of printing and post-processing methods, component design and material development as well as the resulting component performance remain a challenge. This is precisely where the working group applying for funding comes in. On the basis of the new system technology, a significant expansion of the application areas of the MBJ is to be achieved by developing new powder materials, fundamental research into the coordination of the entire production chain, subsequent material/component characterization, as well as by developing predictive load and failure models and, based on this, by working out adapted design rules including shrinkage phenomena. The applicant institutions complement each other thematically in AM, materials development and qualification, powder metallurgy and digital component/process design, in order to be able to comprehensively work on the aforementioned fundamental scientific questions of the MBJ.

直接熔化金属基增材制造（AM）工艺（例如激光粉末床熔合（LPBF））使得可以生产具有高部件密度和几何尺寸精度的几何复杂部件（例如拓扑优化的网格结构）。然而，低组装率和相关的高部件成本阻碍了广泛的工业应用，特别是在成本驱动的工业领域，如汽车行业。AM生产率的必要提高可以通过进一步开发间接粉末床AM工艺来解决，例如具有显著更高堆积率的金属粘合剂喷射（MBJ）。20世纪90年代开发的MBJ逐层打印概念在工艺顺序方面与LPBF工艺相当。然而，MBJ使用多喷嘴打印头来选择性地将粘合剂微滴应用到粉末床，而不是聚焦激光束。在施加粘合剂之后，粉末床在安装空间中下降一层，并施加另一层。重复粉末施加、粘合剂施加、粉末床降低的步骤，直到部件完全组装。在印刷过程之后，粉末床被固化，由此粘合剂的液体组分蒸发。固化的粘合剂-聚合物和金属粉末形成固体绿色部件，其允许去除未渗透的粉末。然后将该绿色坯体在接近熔化温度的炉中烧结。在此过程中，粘合剂热溶解。除了速度优势外，MBJ烧结还提供了比直接AM工艺更大的优势，例如在加工难以焊接的硬质金属或合金方面。由于最近新成立的工业公司如惠普进入MBJ领域，与MBJ之前的可能性相比，有了明显的发展。然而，印刷和后处理方法的开发、部件设计和材料开发以及由此产生的部件性能仍然是一个挑战。这正是申请资金的工作组发挥作用的地方。在新系统技术的基础上，通过开发新的粉末材料，对整个生产链的协调进行基础研究，随后进行材料/部件表征，以及通过开发预测性负载和故障模型，并在此基础上制定包括收缩现象在内的适应性设计规则，MBJ的应用领域将得到显著扩展。申请机构在AM，材料开发和认证，粉末冶金和数字部件/工艺设计方面相互补充，以便能够全面研究MBJ的上述基础科学问题。