Evaluating Material Property Variations in Components With Difficult Geometries

Abstract

All manufacturing methods produce components which have some degree of inhomogeneous properties. Part properties may vary with location in most fabrication methods including additive manufacturing, casting, forging, welding, and surface modifications. Standard tensile test specimens cannot provide a good map of the properties of the material, except for only the largest of components or simplest of geometries. For example, simple curved shapes, such as pipes cannot be reliably evaluated by straight tensile specimens unless the pipe diameter is large enough to have a sufficiently low curvature from which flat specimens can be machined. This paper will look at part property variations in various components made by different fabrication methods, which include selective laser melting, press and sinter powder metallurgy, rolling and casting. Subsize tensile specimens developed at the Missouri University of Science and Technology have been used to map out material properties with location. This method of mapping out properties provides new information which could be valuable to quality control, process control, and design of components.