SBIR Phase I: Vacuum Arc Control using Arc Position Sensing and Induced Magnetic Fields

这个小企业创新研究第一阶段项目将为特种金属行业（钛和镍的制造商）提供40多年来的第一次技术进步。特种金属在我们的生活中无处不在，从飞机零件到医疗植入物的应用，然而真空电弧重熔（VAR）工艺，这个行业的主力，自20世纪40年代发展以来，一直保持相对不变。通过在VAR中测量用于熔化这些高价值合金的电弧位置的能力，以及控制电弧的能力，可以实现大量的电力节约，降低消费者的成本，提高最终产品的可靠性。例如，众所周知，由于缺乏对工艺动态的了解，估计会导致8%的产量损失，由于产量损失和电气效率低下，美国工业每年损失10.24亿美元的收入，导致这些产品的高价格。该项目建议通过开发一种应用反馈控制技术来减少50%的损失，该技术能够优化这些系统中的能量分配，以更低的生产价格提供更高质量的金属。这个项目的智力价值是证明实时控制可以改善基于等离子体的工业处理系统。这项创新利用外部施加的磁场来控制熔化过程中的电弧位置模式。通过耦合电弧位置传感，通过测量过程外部的磁场矢量来确定过程内部的电弧位置，通过主动操纵外部导出的场，可以精确控制电弧。依靠多年来电弧位置传感技术的发展和验证，再加上有限元分析仿真和实验验证，该技术将成为首个主动控制电弧熔化系统的技术。重要的实现是，如果将验证的电流位置测量系统与外场发生器耦合，可以精确控制漫射电流路径的时空控制。这项工作将侧重于VAR炉的应用，但也可能在其他具有漫射电流途径的工艺中有重要应用，如焦耳加热系统、燃料电池、增材制造或工业微波加工。在熔化过程中电弧控制的预期影响是减少制造缺陷，使锭的直径增加，减少合金生产所需的能量，并提高操作的安全性。

This Small Business Innovation Research Phase I project will provide the first technical advancement in the specialty metals industry (manufacturers of titanium and nickel) in more than 4 decades. Specialty metals are ubiquitous in our lives, with applications from aircraft parts to medical implants, yet the vacuum arc remelting (VAR) process, the work horse for this industry, has remained relatively unchanged since its development in the 1940?s. By coupling the ability to measure the location of electric arcs used for melting these high value alloys in the VAR, with the ability to steer the arcs, substantial electrical savings can be achieved, decreasing costs to the consumer and increasing reliability of the final products. For example, it is well known that the lack of understanding of the dynamics of the process leads to an estimated 8% yield loss, costing the US industry $1.024B per year in lost revenue through yield loss and electrical inefficiency, contributing to the high price of these products. This project proposes to decrease this loss by 50% by developing an applied feedback control technology capable of optimizing the energy distribution within these systems, providing better quality metals at a cheaper production price.The intellectual merit of this project is to prove that real-time control can improve plasma-based industrial processing systems. The innovation uses externally applied magnetic fields to manipulate arc position modes during melting operations. By coupling arc position sensing, which measures magnetic field vectors exterior to the process to determine arc positions interior to it, with active manipulation of externally derived fields, arcs can be precisely controlled. Relying upon years of development and validation of arc position sensing, coupled with Finite Element Analysis simulations and experimental validation, this technology will become the first active control of arc melting systems. The significant realization is that spatial and temporal control of the diffuse current paths can be controlled precisely if the validated measurement system of current location is coupled with external field generators. This effort will focus on the application to VAR furnaces but may have significant application to other processes with diffuse current pathways such as Joule heated systems, fuel cells, additive manufacturing or industrial microwave processing. The expected impact of arc control during melting is a reduction in manufacturing defects, an enablement of the production of ingots with increasing diameter, a reduction in energy required in alloy production, and improved safety of operations.