SBIR Phase I: Development of a Metal Aggregate Rapid Tooling Process for Casting Aluminum Alloys

SBIR 第一阶段：开发用于铸造铝合金的金属骨料快速模具工艺

• 批准号: 0512120
• 负责人: Charles Nelson
• 金额: --
• 依托单位: Morris Bean & Company
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2005-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0512120&HistoricalAwards=false
• 关键词: SBIR; Phase; Development; Metal; Aggregate

This Small Business Innovation Phase I Research project aims to develop a novel rapid tooling material for inexpensive production of low volume and prototype castings. This rapid tooling material offers the ease of molding typical to sand molding yet is comparable in properties and performance to metallic permanent molds. The mold comprises a metallic aggregate with a silicate binder, thermally processed to achieve appropriate hardness and dimensional stability. The project will address the following: (1) manufacturing of a complex mold; (2) characterization of the mold material; (3) analysis of the dimensional accuracy and surface roughness of castings produced with this mold; (4) determination of the cooling rates during solidification of aluminum cast in the mold; (5) evaluation of the thermal fatigue resistance and durability of the mold; (6) determination of the lead time to fabricate rapid tooling by this method; Castings made in these molds are expected to cool faster resulting in higher ultimate strength, ductility and elongation. In addition, because of the finer dendrite arm spacing, a shorter homogenization time during heat-treating is anticipated. These attributes make this material attractive not only for rapid tooling but also for contoured chills in sand casting. These would be used to increase local extraction of heat from solidifying aluminum, thereby improving mechanical properties in critical sections of the casting.The broader (commercial) impact from this project would be a metallic aggregate mold technique that lends itself to rapid and inexpensive forming of molds for prototype development castings. The mold so produced has potential applications in metal mold casting processes such as gravity permanent mold, low pressure and die-casting and injection molded plastic parts. The most apparent commercial application for the metal aggregate is in molds for low volume, high strength aluminum castings. Used as a permanent mold the metal aggregate mold provides integral venting, eliminating the need for mechanically created vents thus saving time and cost. Another potential application of the metal aggregate material is in manufacturing of shaped chills for sand casting. As a moldable material the metal aggregate fits the pattern to form a thermally conductive mold otherwise not readily achievable. The company's principal product is aluminum impellers made by a process, which utilizes a combination of permanent and sand molds. Core gases trapped by the permanent mold during the casting process are a major cause of defects, resulting in scrap rates in excess of five percent. A durable, permeable tool could substantially reduce that tooling cost, leading to more rapid implementation of impeller innovations, hence more energy efficient refrigeration designs.

这个小型企业创新第一阶段研究项目旨在开发一种新的快速模具材料，用于低成本地生产小批量和原型铸件。这种快速模具材料提供了典型的砂模成型的简易性，但在性能和性能方面与金属永久模相当。该模具由带有硅酸盐粘结剂的金属集合体组成，经过热处理以获得适当的硬度和尺寸稳定性。该项目将涉及以下内容：(1)制造复杂的模具；(2)模具材料的表征；(3)分析使用该模具生产的铸件的尺寸精度和表面粗糙度；(4)确定铸铝在模具中凝固时的冷却速度；(5)评估模具的热疲劳性和耐久性；(6)确定用这种方法制造快速模具所需的交货期；使用这些模具生产的铸件预计冷却速度更快，从而获得更高的最终强度、延展性和延伸率。此外，由于枝晶臂间距更细，预计热处理过程中的均化时间更短。这些属性使这种材料不仅对快速模具有吸引力，而且对砂型铸造中的轮廓冷铁也很有吸引力。这将被用来增加凝固铝的局部热量提取，从而改善铸件关键部分的机械性能。该项目的更广泛的(商业)影响将是一种金属聚合体模具技术，它有助于快速和廉价地形成原型开发铸件的模具。该模具在金属型铸造工艺中具有潜在的应用前景，如重力金属型、低压压铸型、注塑件等。金属骨料最明显的商业应用是在小体积、高强度铝铸件的模具中。作为永久性模具使用，金属聚合体模具提供整体排气，不需要机械制造排气口，从而节省时间和成本。金属集料材料的另一个潜在应用是制造砂型铸造用冷铁。作为一种可模塑材料，金属聚集体适合形成导热模具，否则很难实现。该公司的主要产品是采用金属型和砂型相结合的工艺制造的铝叶轮。在铸造过程中，金属型芯积聚的气体是缺陷的主要原因，导致废品率超过5%。耐用、透气的工具可以大大降低工具成本，从而更快地实施叶轮创新，从而实现更节能的制冷设计。