SBIR Phase II: Rapid Superplastic Forming of Titanium Matrix Composites

该小型企业创新研究（SBIR）第二阶段项目将联合收割机颗粒增强钛金属基复合材料（PRMMC）与创新的成型工艺相结合，生产飞机发动机管道。 金属基复合材料，在高温下的刚度设计是非常困难的，形成有用的形状。 一种独特的现象，内应力超塑性，通过在钛PRMMC中产生均匀的粘性流动，在通过同素异形相变温度范围的重复热循环期间仅施加轻的应力，来规避成形问题。 阶段I产生了近300%的单轴拉伸。 第二阶段工艺开发将通过利用先进的红外加热（以每分钟1-4个循环的快速热循环）将PRMMC复合材料转变成有用的轴对称管状形状，例如用于商用飞机发动机上的管道，以在30分钟的超塑性成形中将预成型管“吹塑”成最终几何形状。 该项目将按比例扩大单轴的结果，以多轴板材胀形和管材胀形过程的4英寸12英寸的规模。 最后一个部件将复制航空发动机行业的管道部件。 商业应用包括飞机发动机管道、热交换器管道、海上管道配件和阀门等部件。 复杂形状的部件，特别是那些需要高强度和耐腐蚀性的轴对称部件，将受益于这项技术。 预计这些应用将跨越许多市场领域，包括航空航天、工业和消费市场。

This Small Business Innovation Research (SBIR) Phase II project will combine particulate reinforced titanium metal matrix composites (PRMMC) with an innovative forming process to produce aircraft engine ducting. Metal matrix composites, designed for stiffness at elevated temperatures are extremely difficult to form into useful shapes. A unique phenomenon, internal stress superplasticity, circumvents the forming problem by producing uniform viscous flow in titanium PRMMC's with only a light applied stress during repeated thermal cycling through the allotropic phase transformation temperature range. Phase I produced uniaxial stretching of nearly 300%. Phase II process development will transform PRMMC composite into useful axisymmetric tubular shapes, such as used for ducting on commercial aircraft engines, by utilizing advanced infrared heating (rapid thermal cycling at 1-4 cycles per minute) to "blow mold" a preform tube into final geometry in 30 minutes of superplastic forming. The project will scale up uniaxial results to multiaxial sheet bulging and tube bulging processes on a 4 inch by 12 inch scale. The final component will replicate a duct component from the aerospace engine industry. Commercial applications include components such as aircraft engine ducting, heat exchanger tubing, offshore pipe fittings, and valves. Complex shaped components, particularly those axisymmetric in nature which require high strength and corrosion resistance, will benefit from this technology. It is anticipated that these applications will span many market areas including aerospace, industrial, and consumer markets.