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The purpose of this paper is to investigate the effect of preheat and layer thickness in selective laser melting (SLM) of magnesium using pulse mode. Magnesium has been considered as a new generation of implant materials which are bioactive and biodegradable for orthopaedic applications.

To produce optimal single magnesium tracks to compare the effect of layer thickness and preheat, different laser parameters were investigated. The analysis was made based on digital and electronic microscope images and mechanical measurements.

Improvements in the magnesium tracks due to preheating were successfully achieved. The analysis shows better bonding to the surface. The preheated tracks present an improvement in quality surface: smoother and flatter surfaces are discovered for the low layer thicknesses. When the thickness increases, the surface was disrupted and presented high surface roughness values. These were attributed to the Marangoni convection.

This study continues valuing the fabrication of magnesium with SLM. It shows the improvements of preheat and effect of different layer thicknesses on the part properties.

Magnesium has been considered as a new generation of bioactive and biodegradable implant for orthopaedic applications because of its prominent properties including superior biocompatibility, biodegradability and proper mechanical stiffness. For the direct production of custom biomedical implants, selective laser melting (SLM) has been investigated to fabricate pure magnesium and its resultant properties. The primary objective of this paper is to identify the most appropriate mode of irradiation for the melting of pure magnesium powders due to its reactive properties. This study focuses on investigating the interaction between the laser source and the magnesium powders by varying the SLM parameters of the laser power and scan speed under continuous or pulse mode conditions.

Single magnesium tracks were fabricated under different processing conditions using SLM, in order to evaluate the effects of processing parameters on the dimension and surface morphology of the achieved parts. The digital images of the tracks were used to analyze the geometrical features in terms of melting width and depth. In addition, scanning electron images were also studied to understanding the selective melting mechanism.

Magnesium tracks were successfully fabricated using SLM. Results showed that the dimension, surface morphology and the oxygen pick‐up of the laser‐melted tracks are strongly dependent on the mode of irradiation and processing parameters.

This work is a first step towards magnesium fabrication using SLM technique. The experimental results represent an important step in understanding the magnesium under an Nd:YAG laser irradiation, which provides the basis of behavior for follow‐on research and experiments.

The purpose of this paper is to outline some key aspects such as material systems used, phenomenological and statistical process modeling, techniques applied to monitor the process and optimization approaches reported. All these need to be taken into account for the ongoing development of the SLM technique, particularly in health care applications. The outcomes from this review allow not only to summarize the main features of the process but also to collect a considerable amount of investigation effort so far achieved by the researcher community.

This paper reviews four significant areas of the selective laser melting (SLM) process of metallic systems within the scope of medical devices as follows: established and novel materials used, process modeling, process tracking and quality evaluation, and finally, the attempts for optimizing some process features such as surface roughness, porosity and mechanical properties. All the consulted literature has been highly detailed and discussed to understand the current and existing research gaps.

With this review, there is a prevailing need for further investigation on copper alloys, particularly when conformal cooling, antibacterial and antiviral properties are sought after. Moreover, artificial intelligence techniques for modeling and optimizing the SLM process parameters are still at a poor application level in this field. Furthermore, plenty of research work needs to be done to improve the existent online monitoring techniques.

This review is limited only to the materials, models, monitoring methods, and optimization approaches reported on the SLM process for metallic systems, particularly those found in the health care arena.

SLM is a widely used metal additive manufacturing process due to the possibility of elaborating complex and customized tridimensional parts or components. It is corroborated that SLM produces minimal amounts of waste and enables optimal designs that allow considerable environmental advantages and promotes sustainability.

The key perspectives about the applications of novel materials in the field of medicine are proposed.

The investigations about SLM contain an increasing amount of knowledge, motivated by the growing interest of the scientific community in this relatively young manufacturing process. This study can be seen as a compilation of relevant researches and findings in the field of the metal printing process.