Additive Manufacturing of Magnetostrictive Fe-Co Alloys.

Fe-Co alloys are attracting attention as magnetostrictive materials for energy harvesting and sensor applications. This work investigated the magnetostriction characteristics and crystal structure of additive-manufactured Fe-Co alloys using directed energy deposition. The additive-manufactured Fe-Co parts tended to exhibit better magnetostrictive performance than the hot-rolled Fe-Co alloy.

Interface Control in Additive Manufacturing of Dissimilar Metals Forming Intermetallic Compounds-Fe-Ti as a Model System.

Laser metal deposition (LMD) has demonstrated its ability to produce complex parts and to adjust material composition within a single workpiece. It is also a suitable additive manufacturing (AM) technology for building up dissimilar metals directly. However, brittle intermetallic compounds (IMCs) are formed at the interface of the dissimilar metals fabricated by LMD.

Epitaxial Growth of Silicon on Silicon Wafers by Direct Laser Melting.

Additive manufacturing (AM) of brittle materials remains challenging, as they are prone to cracking due to the steep thermal gradients present during melting and cooling after laser exposition. Silicon is an ideal brittle material for study since most of the physical properties of single-element materials can be found in the literature and high-purity silicon powders are readily available. Direct laser melting (DLM) of silicon powder was performed to establish the conditions under which cracks occur and to understand how the solidification front impacts the final microstructure.

Effects of Processing Parameters on Mechanical Properties of Silicon Carbide Nanoparticle-Reinforced Aluminium Alloy Matrix Composite Materials.

Nano-silicon carbide (nSiC) particle-reinforced aluminium (Al) 6061 alloy matrix composites were fabricated by high-energy ball milling, hot-pressing (HP), and hot-forging (HF). The composite powders were degassed and the composites were synthesised under air and/or vacuum. Mechanical properties of the obtained composite materials were evaluated using various tests, including indentation, compression, four-point bending, and tensile tests as well as by microstructural observations.

Fabrication of Metal Matrix Composite by Laser Metal Deposition-A New Process Approach by Direct Dry Injection of Nanopowders.

Laser Metal Deposition (LMD) offers new perspectives for the fabrication of metal matrix nanocomposites (MMnCs). Current methods to produce MMnCs by LMD systematically involve the premixing of the nanopowders and the micropowders or require in-situ strategies, thereby restricting the possibilities to adjust the nature, content and location of the nano-reinforcement during printing. The objective of this study is to overcome such restrictions and propose a new process approach by direct injection of nanoparticles into a metallic matrix.

Hot extruded carbon nanotube reinforced aluminum matrix composite materials.

Carbon nanotube (CNT) reinforced aluminum (Al) matrix composite materials were successfully fabricated by mechanical ball milling followed by powder hot extrusion processes. Microstructural analysis revealed that the CNTs were well dispersed at the boundaries and were aligned with the extrusion direction in the composites obtained. Although only a small quantity of CNTs were added to the composite (1 vol%), the Vickers hardness and the tensile strength were significantly enhanced, with an up to three-fold increase relative to that of pure Al.

Dual-nanoparticulate-reinforced aluminum matrix composite materials.

Aluminum (Al) matrix composite materials reinforced with carbon nanotubes (CNT) and silicon carbide nanoparticles (nano-SiC) were fabricated by mechanical ball milling, followed by hot-pressing. Nano-SiC was used as an active mixing agent for dispersing the CNTs in the Al powder. The hardness of the produced composites was dramatically increased, up to eight times higher than bulk pure Al, by increasing the amount of nano-SiC particles.

Carbon nanofiber reinforced aluminum matrix composite fabricated by combined process of spark plasma sintering and hot extrusion.

Spark plasma sintering and hot extrusion processes have been employed for fabricating carbon nanofiber (CNF)-aluminum (Al) matrix bulk materials. The Al powder and the CNFs were mixed in a mixing medium of natural rubber. The CNFs were well dispersed onto the Al particles.