Net-Shape Die Casting of Complex Parts

复杂零件的净形压铸

• 批准号: 8815855
• 负责人: Kuo Wang
• 金额: $ 43.17万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-07-15 至 1993-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8815855&HistoricalAwards=false
• 关键词: Net; Shape; Die; Casting; Complex

Die casting is the most effective process to mass produce complex metal parts to tight tolerance at low cost. However, the traditional die-casting process can only produce near-net-shape, and always requires a secondary operation to trim off overflows and gates. Further, a more serious problem (particularly for complex parts) is the uncertainty of having porosity somewhere in the part caused by turbulent flow during the process, which is difficult to detect. This inherent disadvantage may have been a major factor in the slow growth of the seven-billion-dollar industry which is facing stiff competition from other processes like injection molding of plastics as well as foreign die-casting producers, due to lack of technical edge. It is necessary to develop a process that can produce net-shape parts akin to such processes as injection or transfer molding of polymers. The idea is to make use of the so-called "semi-solid alloy" (a slurry of solid particles suspended in a molten metal matrix) which has high viscosity and can be processed in the laminar-flow regime. The main objectives are to study the rheology of such materials, develop simulation models for flow and solidification, and design a new machine for experiments. Successful completion of this research would have a potential to revolutionize the die-casting technology and provide our industry an edge over foreign competition in this area.

压铸是大批量生产低成本、高公差的复杂金属零件的最有效方法。然而，传统的压铸工艺只能产生近净形状，并且总是需要二次操作来修剪溢流和浇口。此外，一个更严重的问题（特别是对于复杂的零件）是由于在加工过程中湍流导致的零件某处存在孔隙的不确定性，这很难检测到。这种固有的劣势可能是这个70亿美元产业增长缓慢的一个主要因素。由于缺乏技术优势，该产业正面临着其他工艺的激烈竞争，如塑料注射成型和外国压铸生产商。有必要开发一种可以生产净形状零件的工艺，类似于聚合物的注射或传递成型等工艺。这个想法是利用所谓的“半固态合金”（一种悬浮在熔融金属基体中的固体颗粒浆），它具有高粘度，可以在层流状态下处理。主要目的是研究这些材料的流变学，建立流动和凝固的模拟模型，并设计一种新的实验机器。这项研究的成功完成将有可能彻底改变压铸技术，并为我国工业在这一领域的国外竞争提供优势。