3D printing of multiple metallic materials via modified selective laser melting

Abstract

Selective Laser Melting (SLM) is a powder bed layer-by-layer fusion technique mainly applied for additive manufacturing of 3D metallic components of complex geometry. However, the technology is currently limited to printing a single material across each layer. In many applications such as the manufacture of certain aero engine components, conformably cooled dies, medical implants and functional gradient structures, printing of multiple materials are desirable. This paper reports an investigation into the 3D printing of multiple metallic materials including 316L stainless steel, In718 nickel alloy and Cu10Sn copper alloy within a single build-up process using a specially designed multiple material SLM system combining powder-bed with point by point powder dispensing and selective material removal, for the first time. Material delivery system design, multiple material interactions, and component characteristics are described and the associated mechanisms are discussed. 3D printing, selective laser melting, multiple materials 2. Experimental materials and procedure 2.1. Materials Gas atomized spherical 316L stainless steel powder (LPW-718-AACF, 10-45 µm, LPW Technology Ltd., UK), In718 nickel alloy powder (LPW-316-AAHH, 10-45 µm LPW Technology Ltd., UK), Contents lists available at SciVerse ScienceDirect CIRP Annals Manufacturing Technology

Embedding anti-counterfeiting features in metallic components via multiple material additive manufacturing

“…This makes multiple material SLM a promising method to imbed the tiny QR codes into the metallic components manufactured fully or partially with additive manufacturing. The University of Manchester demonstrated a novel ultrasonic selective powder delivery integrated into powder bed SLM [31] ……" 2) While barcodes embedded into the part are non-removable and not visible unless one inspects it with proper equipment, it is easy to detect for very stubborn malicious agent. When it is detected, what stops that malicious agent from fabricating parts with embedded barcode (counting availability of multi-material SLM machine)?…”

“…The multiple material SLM process procedure was demonstrated in the previous work [31]. As presented in Fig.…”

“…This makes multiple material SLM a promising method to imbed tiny QR codes into the metallic components manufactured fully or partially with additive manufacturing. The University of Manchester demonstrated a novel ultrasonic selective powder delivery system integrated into powder bed SLM [31], which showed the potential for applications for the tailoring of local material prosperities in a component (e.g. medical implants), printing of mechanical-electronic integrated components (e.g.…”

Multi-Cycle Process Signature of Laser-Induced Thermochemical Polishing

“…Conventional polishing processes face a major challenge for filigree micro-and mesoscale metallic parts or for complex geometries [6] and multi-material composition [7] of additive manufactured parts [8]. Polishing such parts requires a minimum thermal and mechanical energy impact and a high grade of automatization [9].…”

Effects of Gas Nitriding on Fatigue and Crack Initiation of Ti6Al4V produced by Selective Laser Melting

“…Selective Laser Melting (SLM), is an established technique in additive manufacturing (AM). SLM uses a high-power laser beam to fully melt powdered material placed on a flat surface, layer-by layer, to build three dimensional solid models with high density and usefully high mechanical properties [1][2][3] . The SLM process has been widely studied for different metallic powders, including: steels, titanium, nickel, tungsten, aluminium and copper alloys/composites [4][5][6][7][8][9][10] .…”