The heating and cooling profiles experienced during laser additive manufacturing results in residual stresses build up in the component. Therefore, it is necessary to perform post build stress relieving towards the retention and improvement of the mechanical properties. However the thermal treatments for conventional manufacturing do not seem to completely accommodate these rapid heating and cooling cycles of laser processing techniques such as powder bed fusion. Characterizations such as density measurements on the samples were performed employing the Archimedes principle; hardness testing was performed on the Zwick micro/macro (Hv) hardness tester, SEM and Electron backscatter diffraction (EBSD). Fracture toughness and crack growth was conducted on a fatigue crack machine. All characterization was done after stress relieving of Selective Laser Melting (SLM) produced samples at 300 °C for 2 hrs was performed in a furnace. The mechanical properties appear to be rather compromised instead of being enhanced desirably. As-built SLM produced tensile specimens built in different directions exhibited significantly favorable mechanical properties. However, post stress relieve thermal treatment technique deteriorated the strength while increasing the ductility significantly. Nonetheless, fatigue crack growth and fracture toughness illustrated positive outcome in terms of fatigue life on SLM produced AlSi10Mg components in application.

A cutting-edge manufacturing technology that uses powder or wire as the feeding material and a high-energy heating source is known as metal additive manufacturing (AM). High-performance components for automotive, aerospace, medical, and energy applications are designed and produced using additive manufacturing (AM). In this overview, only laser additive manufacturing (LAM) procedures such as powder bed fusion (PBF) and directed energy deposition are discussed (DED). LAM provides an alternate path for fabricating current designs and permits the creation of new designs with complexity that is not possible with conventional methods. One of the most promising forms of additive manufacturing is laser additive manufacturing, which may produce things at low cost while keeping high value and yield (LAM). Specifically, when it comes to directed energy deposition (DED) or powder bed fusion (PBF), which involve various types of wire-fed, powder fed, and powder-bed assembly, it examines the key metallurgical phenomena that occur during LAM as well as the distinctions between different LAM technological pathways. This study offers a thorough overview of the classification of LAM systems, applications of LAM processes, key processing factors, frequent flaws, mechanical characteristics of manufactured parts, numerous machine-related parameters, and optimization of deposition conditions.

In additive manufacturing, powder characteristics play an important role in terms of flowability and densification, which can be improved by the use of spherical powders. In this study, irregular powder was spheroidised by plasma treatment, and the powder properties were measured. Powder characterisation was conducted to determine the morphology, particle size and distribution as well as the flowability. Spherical AISI 304 stainless steel powders were produced by plasma spheroidization, and the efficiency of the spheroidisation process was evaluated. The spheroidisation process resulted in 93% efficiency with a decrease of fine particles (<63 µm) by 22%, while the all the flowability parameters of the powder improved significantly.

The AlSi10Mg alloy is known for its castability, corrosion resistance, high heat conductivity, low weight and good weldability. Applications of the aluminium alloy components includes heat exchangers that are subjected to high temperatures and corrosive environments. The production process of AlSi10Mg alloy using selective laser melting has been extensively explored because of its hypoeutectic composition of Al and Si. However, it has been observed that stress relieve has a negative consequence on tensile properties of SLM built samples, while retaining and improving ductility. The thermal behaviour of AlSi10Mg alloy fabricated by selective laser melting with the specimen heat treated at 300°C for 2 hours investigated in this work. The specimens exhibited mass gain during the thermalgravimetric analysis as a result of the precence of oxygen as one of the elements present as detected by the elemental analysis. The fatigue results post thermal treatment demonstrated improved fatigue resistance qualities comparable to die-casted AlSi10Mg.