A bottom-up approach to experimentally investigate the deposition of austenitic stainless steel in laser direct metal deposition system

Abstract

Direct metal deposition (DMD) is a method of metallic part fabrication under the classification of additive manufacturing process. In DMD, parts are manufactured by melting powder particles reaching the deposition zone, layer by layer with a laser beam. This potential process promises manufacturing flexibility of complex shapes deposition with a range of challenging materials. The work presents the establishment of laser, powder and deposition parameters in a newly developed metal-based direct laser deposition system. The experiments are performed using a 1.2-kW diode laser of 976-nm wavelength coupled with coaxial fed powder delivery nozzle. Geometrical characteristics and mechanical properties of the deposited single-wall, multi-layer wall are determined and discussed. The study also discusses some of the challenges met during the deposition and their potential resolutions. Issues with uniformity of layer width, layer height and mechanical properties such as surface finish and micro-hardness are addressed. The specific aim of this experimental work is to effectively control the process parameters towards building a sound thin wall clad deposition and to further use those parameters for the development of a functional 3D component. A 3D functional component is deposited using 300 W laser power, 4 mm/s scanning speed, 1.05 g/ min powder feed rate and 50% overlap ratio which shows a good geometrical resemblance with the original part. The study thus can provide intuitive guidance for deposition to metal additive manufacturing enthusiasts.

Fabrication of Thin Walls with and without Close Loop Control as a Function of Scan Strategy Via Direct Energy Deposition

“…Also, gradually the layers were seen to be bent through the middle. Due to this effect gradual reduction of laser power is advised by many researchers [6,10,28,29]. By manually reducing power by 100 W with each successive layer (Fig.…”

“…The fabrication of such thin-walled structures is quite challenging due to complex stress distribution [5]. Also, it is often of interest to know the smallest possible feature which is geometrically consistent to be manufactured by DED [6]. Effective control of process parameters such as scan speed, laser speed, feed rate etc.…”

Analysis of novel induction heating extruder for additive manufacturing using aluminum filament

“…1,2 Among them the well-known metal deposition processes of AM are DED and PBF. 3–6 However the limitations associated with these AM methods are low deposition rates and high equipment cost. 7 An aspiring method to process metal is the material extrusion, which is commonly known to handle materials like polymers.…”

On the Features of Composite Coating, Based on Nickel Alloy and Aluminum–Iron Bronze, Processed by Direct Metal Deposition

“…The formation of macrocracks was fixed upon deposition with the minimum of excess, whereas only microcracks were observed when it increased. Pant et al [ 27 ] defined and discussed the geometrical characteristics and mechanical properties of single-layer and multi-layer walls when DMD processing with a coaxial-powder flow of 316 L steel, depending on the laser power, the laser spot speed, the intensity of the powder feeding, and overlapping factors. Ni et al [ 28 ] researched the influence of coaxial nozzle parameters on gas flow and the powder distribution on the surface formed by the DMD method and showed that the correct choice of these parameters ensures good morphology and quality of the deposited layer.…”