Ultrasonic Characterization of Components Manufactured by Direct Laser Metal Deposition

Direct laser metal deposition (DLMD) is an innovative additive technology becoming of key importance in the field of repairing applications for industrial and aeronautical components. The performance of the repaired components is highly related to the intrinsic presence of defects, such as cracks, porosity, excess of dilution or debonding between clad and substrate. Usually, the quality of depositions is evaluated through destructive tests and microstructural analysis. Clearly, such methodologies are inapplicable in-process or on repaired components. The proposed work aims to evaluate the capability of ultrasonic techniques to perform the mechanical characterization of additive manufactured (AM) components. The tested specimens were manufactured by DLMD using a nickel-based superalloy deposited on an AISI 304 substrate. Ultrasonic goniometric immersion tests were performed in order to mechanical characterize the substrate and the new material obtained by AM process, consisting of the substrate and the deposition. Furthermore, the relationship was evaluated between the acoustic and the mechanical properties of the AM components and the deposition process parameters and the geometrical characteristics of multiclad depositions, respectively. Finally, the effectiveness of the proposed non-destructive experimental approach for the characterization of the created deposition anomalies has been investigated.

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2D longitudinal modeling of heat transfer and fluid flow during multilayered direct laser metal deposition process

Journal of Laser Applications ◽

10.2351/1.4726445 ◽

2012 ◽

Vol 24 (3) ◽

pp. 032008 ◽

Cited By ~ 61

Author(s):

Simon Morville ◽

Muriel Carin ◽

Patrice Peyre ◽

Myriam Gharbi ◽

Denis Carron ◽

...

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Deposition Process ◽

Metal Deposition ◽

Longitudinal Modeling ◽

Laser Metal Deposition ◽

Direct Laser ◽

Direct Laser Metal Deposition

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A Methodology for Optimization of the Direct Laser Metal Deposition Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.473.75 ◽

2011 ◽

Vol 473 ◽

pp. 75-82 ◽

Cited By ~ 11

Author(s):

Andrea Angelastro ◽

Sabina L. Campanelli ◽

Giuseppe Casalino ◽

Antonio D. Ludovico ◽

Simone Ferrara

Keyword(s):

Optimization Procedure ◽

Deposition Process ◽

Metal Deposition ◽

Hard Coatings ◽

Full Density ◽

Laser Metal Deposition ◽

Scanning Velocity ◽

3D Cad ◽

Direct Laser ◽

Direct Laser Metal Deposition

Direct Laser Metal Deposition (DLMD) is actually one of the most attractive techniques in the group of Material Accretion Manufacturing (MAM) processes. In fact, the DLMD technology is able to realize, to repair and restore, objects, moulds and tools, directly from the 3D CAD model in a rapid and economic way. A great variety of metals, including those very difficult to work with the conventional techniques, can be shaped in a large number of complex geometries. This technique is also well suited to produce very hard coatings. The metallic parts, which are obtained through melting coaxially fed powders with a laser, present very good mechanical properties, with minimum porosity and good adhesion to the substrate. The objective of this work was to optimise the scanning velocity of the laser beam in order to maximize the density of DLMD parts. The optimization procedure was worked out with a mathematical model together with an experimental analysis to study the shape of the track clad generated melting coaxially fed powders with a laser. The material tested was Colmonoy 227-F, a nickel alloy specially designed for manufacturing moulds. The presented methodology has permitted to select the better combination of parameters that produce almost full density parts, free of cracks and well bonded to the substrate sintered parts.

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