Development of low-pressure powder injection molding feedstocks to increase the moldability of metallic complex shape parts

开发低压粉末注射成型原料以提高金属复杂形状零件的成型性

• 批准号: RGPIN-2018-04407
• 负责人: Demers, Vincent
• 金额: $ 2.04万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 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=712990
• 关键词: Development; low; pressure; powder; injection

CONTEXT: Low-pressure powder injection molding (LPIM) is an advanced manufacturing process used for the cost-effective and small series fabrication of net-shape components with similar metal casting shape complexity. The technology takes advantage of low-viscosity feedstocks (wax-based binder mixed with powder) to achieve high moldability during the injection step. During the subsequent debinding and sintering treatments, the binder is completely removed from the green part to obtain a dense metallic part. According to the Metal Powder Industries Federation, the market for metal injection molding powders in North America grew by an impressive 510% between 2009 and 2017. Initially used in ceramics shaping, the LPIM process rapidly became attractive for the rapid manufacture of metallic parts in the automotive, aerospace and medical industries. However, the optimization of mechanical properties has been performed with feedstocks whose optimal moldability has not been demonstrated. Therefore, realizing the full potential of the LPIM process is limited by a poor understanding of the mechanisms underlying the moldability of low-viscosity feedstocks, resulting directly from a lack of fundamental knowledge on the rheological behavior of these mixtures. Today, modeling the rheological behavior of the LPIM feedstocks poses many challenges due to the complex interactions between binders and shear thinning behavior of such mixtures. OBJECTIVES: The general objectives of this Discovery Grant proposal are to improve fundamental knowledge on the moldability of low-viscosity feedstocks, and to develop new experimental and simulation tools for predicting the flow behavior of LPIM feedstocks during the injection process. This will be achieved by developing an experimental method to study the moldability of wax-based feedstocks (objective #1), which will then be used to develop and validate a numerical model simulating the injection process (objective #2). Finally, the new numerical model will be exploited to identify the candidate feedstocks demonstrating the best moldability properties which will be then processed (debinding and sintering) in order to evaluate the mechanical properties of LPIM manufactured parts (objective #3). OUTCOMES: These LPIM research efforts have the potential to change and influence some process engineering practices by offering an innovative manufacturing method that could lead to real breakthroughs for producing complex shape parts from hard metallic materials with the proper dimensional tolerances, which is one of the main goals of the Canadian manufacturing industry. The impact of this research program will also be felt in the form of training of highly qualified people, results dissemination in open access repositories, and technology transfer in competitive key areas, such as the aerospace, petroleum, health technologies, and many more sectors.

背景：低压粉末注射成型 (LPIM) 是一种先进的制造工艺，用于经济高效地小批量制造具有类似金属铸造形状复杂性的净形部件。该技术利用低粘度原料（与粉末混合的蜡基粘合剂）在注射步骤中实现高成型性。在随后的脱脂和烧结处理过程中，粘合剂从生件中完全去除，以获得致密的金属部件。据金属粉末工业联合会称，2009 年至 2017 年间，北美金属注射成型粉末市场增长了 510%，令人印象深刻。 LPIM 工艺最初用于陶瓷成型，但很快就对汽车、航空航天和医疗行业金属零件的快速制造产生了吸引力。然而，机械性能的优化是使用其最佳成型性尚未得到证实的原料进行的。因此，由于缺乏对这些混合物流变行为的基础知识，对低粘度原料模压机制的了解不足，限制了 LPIM 工艺的全部潜力的发挥。如今，由于粘合剂和此类混合物的剪切稀化行为之间复杂的相互作用，LPIM 原料的流变行为建模面临许多挑战。 目标：该发现资助提案的总体目标是提高有关低粘度原料成型性的基础知识，并开发新的实验和模拟工具来预测注射过程中 LPIM 原料的流动行为。这将通过开发一种实验方法来研究蜡基原料的可成型性（目标＃1）来实现，然后将其用于开发和验证模拟注射过程的数值模型（目标＃2）。最后，将利用新的数值模型来确定具有最佳成型性能的候选原料，然后对其进行加工（脱脂和烧结），以评估 LPIM 制造零件的机械性能（目标#3）。 结果：这些 LPIM 研究工作有可能通过提供创新的制造方法来改变和影响一些工艺工程实践，这种方法可能会在用具有适当尺寸公差的硬质金属材料生产复杂形状零件方面带来真正的突破，这是主要的技术之一加拿大制造业的目标。该研究计划的影响还将体现在高素质人才的培训、开放获取存储库中的成果传播以及航空航天、石油、卫生技术等许多领域的竞争性关键领域的技术转让方面。