Capability of Multi-Material Laser-Based Powder Bed Fusion—Development and Analysis of a Prototype Large Bore Engine Component

Abstract

Additive Manufacturing (AM) allows the manufacturing of functionally graded materials (FGM). This includes compositional grading, which enables the allocation of desired materials corresponding to local product requirements. An upcoming AM process for the creation of metal-based FGMs is laser-based powder bed fusion (PBF-LB/M) utilized for multi-material manufacturing (MM). Three-dimensional multi-material approaches for PBF-LB/M are stated to have a manufacturing readiness level (MRL) of 4 to 5. In this paper, an advancement of multi-material technology is presented by realizing an industry-relevant complex part as a prototype made by PBF-LB/M. Hence, a multi-material injection nozzle consisting of tool steel and a copper alloy was manufactured in a continuous PBF-LB/M process. Single material regions showed qualities similar to the ones resulting from mono-material processes. A geometrically defined transition zone between the two materials was achieved that showed slightly higher porosity than mono-material regions. Nevertheless, defects such as porosity, cracks, and material cross-contamination were detected and must be overcome in further MM technology development.

Development of a maturity model for additive manufacturing: A conceptual model proposal

“…Schneck et al [ 50 ] proposed a breakthrough of multi-material technology by fabricating a complex, industrial multi-material part as a prototype fabricated by laser-based powder bed fusion. With this work, the authors concluded that a maturation of this type of fabrication to a higher MRL was possible [ 50 ]. Wu et al [ 51 ] performed a literature review and evaluated bioprinting based on the proposed criteria of the MRL.…”

Embedding Function within Additively Manufactured Parts: Materials Challenges and Opportunities

“…Regardless of the specific technology in use, much attention in the literature has been paid to embedding functionality through the development of new materials, including alloys and composites, rather than part comprised of multimaterial systems. Generally speaking, multimaterial printing by PBF is still in its infancy, [7] likely because it requires complicated procedures (e.g., the deposition, consolidation, and cleaning of alternating powders' layers [8] ) or extensive hardware customization. [9] Also, multimaterial printing may potentially cause bonding issues at the interface between dissimilar materials, thermal stresses due to the thermodilatometric mismatch, and, in metal-based systems, galvanic corrosion in service, should the materials be bridged by an electrolyte.…”

Research progress in multi-material laser-powder bed fusion additive manufacturing: A review of the state-of-the-art techniques for depositing multiple powders with spatial selectivity in a single layer

“…Another approach for applying powders in a multi-material process combines a full-surface powder deposition with powder removal by suction 24 . An illustration of this approach is shown in Figure 3 where an AconityONE printer was upgraded with a multi-material mobile module that can be installed and removed.…”