Need for NDE references in additive manufacturing: an aerospace perspective

Applications of additive manufacturing (AM) are diversified, but found with preponderance in the automotive, aerospace, and medical fields. The field of additive manufacturing/material 3D printing is advancing extremely fast, and covers a broad range of materials, spanning from plastics to metals, ceramics, and even to biological tissue. In the aerospace industry one of the main points of attraction is that parts with complex shapes can be built on demand while reducing the weight at the same time. The process can also aid in the fabrication of rare parts and replacement components that are no longer in production. It is commonly understood that AM parts would have different types of defects than those found in conventionally manufactured ones, while major gaps in knowledge exists in terms of the defect type, the effect-of-defect, and the critical defect size and location. One of the shortcomings is related to the lack of physical reference blocks for calibration and performance verification of proposed non-destructive evaluation (NDE) techniques. Also, there are no standards for NDE techniques as applied to AM. This article discusses how NDE could better position itself to help AM gain the trust of aerospace industry. (author)