GOALI: Miniature Net-Shape Fabrication Method Using Thermoplastic Forming with Bulk Mettalic Glass

该研究项目的目标是开发一种基于大块金属玻璃（BMG）热塑性成形的微型制造方法。BMGS是一种新型的工程材料，具有非常高的强度、弹性和耐腐蚀性，当在其过冷液体区域中热塑性成型时，可以像塑料一样加工。在所提出的制造方法中，将BMG再加热到过冷液体区域中，在该过冷液体区域中，在所施加的压力下将其模塑成各种形状和尺寸的模具。将建立各种BMG合金在不同模具上的成形压力、加工时间、温度和成形行为之间的相关性，以确定最佳加工条件。为了制造三维零件，制造方法将包括成型工艺、热刮方法和表面平滑工艺，以产生具有超光滑表面光洁度的高精度三维微型零件。为了开发成本有效的方法，必须更换硅模具。由于所需的加工温度不允许使用聚合物模具，或者，使用通过聚合物热解合成的碳模具。如果成功的话，这项研究的结果将奠定一个新的微型制造方法的基础上，热塑性成形与块体金属玻璃。确定工艺参数和成形行为之间的相关性可以用作基于BMG的热塑性成形的广泛工艺的模型描述的基础。在这种方法中，可以以成本有效的方式生产具有最高精度和表面光滑度的三维微型零件。BMG的这些加工优点和优于当前使用的微型成形材料的上级性质表明，所提出的方法可能取代当前使用的微型制造方法作为最具成本效益的方法。

The goal of this Grant Opportunities for Liaison with Industry (GOALI) research project is to develop a miniature fabrication method based on thermoplastic forming with bulk metallic glasses (BMGs). BMGS are a new class of engineering materials with very high strength, elasticity and corrosion resistance that can be processed like plastics when thermoplasically formed in their supercooled liquid region. Within the proposed fabrication method the BMG is reheated into the supercooled liquid region where it is molded under an applied pressure into molds of various shapes and sizes. The correlation between forming pressure, processing time, temperature and forming behavior will be established for various BMG alloys on different molds to determine the optimal processing conditions. In order to create 3-dimensional parts the fabrication method will be comprised of a molding process, a hot-scraping method, and a surface smoothening process, to yield high precision 3-dimensional miniature parts with an ultra smooth surface finish. To develop a cost effective method silicon molds have to be replaced. Since the required processing temperatures do not permit the use of polymer molds, alternatively, the use of carbon molds which are synthesized by the pyrolyzing of polymers. If successful, the results of this research will lay the foundation of a novel miniature fabrication method based on thermoplastic forming with bulk metallic glass. Determining of the correlation between processing parameters and forming behavior can be used as a foundation of a model description of a wide range of processes based on thermoplastic forming with BMGs. Within this method 3-dimensional miniature parts can be produced with highest precision and surface smoothness in a cost effective manner. These processing advantages and the superior properties of the BMG over currently used miniature forming materials suggest that the proposed method might replace currently used miniature fabrication methods as the most cost effective process.