Variability in the Geometric Accuracy of Additively Manufactured Test Parts | NIST

Abstract

A.L. Cooke and J.A. Soons National Institute of Standards and Technology Gaithersburg, MD, USA Abstract This paper describes the results of a study on the variability in the geometric accuracy of a metal test part manufactured by several service providers using either an electron beam or laser beam powder bed thermal fusion process. The part was a circle-diamond-square test part with an inverted cone that is used to evaluate the performance of five-axis milling machines. The study was conducted to aid development of standardized parameters and test methods to specify and evaluate the performance of additive manufacturing systems. Without standards for performance characterization, it is difficult to match system capabilities with part requirements and ensure consistent and predictable part quality across systems, operators, and manufacturing facilities. Introduction There are many additive manufacturing (AM) system vendors with various types of AM systems on the market. No standards exist for the unambiguous specification, comparison, and evaluation of AM system performance. This makes it difficult to match machine/process capabilities with part requirements and ensure consistent and predictable results across systems, operators, and manufacturing facilities. There are many aspects of system performance to consider, such as processing speed, part accuracy, surface finish, maximum part size, minimum feature size, feasibility of overhang features, and part material properties. This paper focuses on part accuracy.