Multi-Material Processing By Lens

Abstract

During the past few years, solid freeform fabrication has evolved into direct fabrication of
\nmetallic components using computer aided design (CAD) solid models. [1-4] Laser Engineered
\nNet Shaping (LENS™) is one such technique [5-7] being developed at Sandia to fabricate high
\nstrength, near net shape metallic components. In the past two years a variety of components have
\nbeen fabricated using LENS™ for applications ranging from prototype parts to injection mold
\ntooling. [8]
\nTo advance direct fabrication capabilities, a process must be able to accommodate a wide
\nrange ofmaterials, including alloys and composites. This is important for tailoring certain
\nphysical properties critical to component performance. Examples include graded deposition for
\nmatching coefficient ofthermal expansion between dissimilar materials, layered fabrication for
\nnovel mechanical properties, and new alloy design where elemental constituents and/or alloys are
\nblended to create new materials. In this paper, we will discuss the development ofprecise
\npowder feeding capabilities for the LENSTM process to fabricate graded or layered material parts.
\nWe also present preliminary results from chemical and microstructural analysis.