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Selective laser melting (SLM) is an important advanced additive manufacturing technology. The existing SLM printing technology cannot manufacture the mechanical parts that fully meet the requirements of high precision and strength. This paper aims to explore a new post-processing method for SLM 316L specimen, namely, using of the TiN/TiAlN multilayer coating fabricated by multi-arc ion plating on the surface of SLM specimens, for improving the performance of SLM specimens. The other purpose of this paper is compared the performances of the TiAlN/TiN multilayer coating machined specimen and the TiN/TiAlN multilayer coating SLM specimen.

The TiN/TiAlN multilayer coating is fabricated by multi-arc ion plating on the surface of 316L specimens. The surface morphology and selected mechanical properties of TiN/TiAlN multilayer coating plating on the SLM substrate specimen and the machined substrate specimen were studied in this paper. The analyzed properties included surface topography, micro hardness, the adhesion, the thickness and the wear resistance of TiN/TiAlN multilayer coating plating on the SLM substrate specimen and the machined substrate specimen.

The electron microscope images reveal that surface morphology of TiN/TiAlN multilayer coating plating on the SLM specimens is relatively flat, and there are some micro-particles in different sizes and pin holes dispersed on them. After TiN/TiAlN multilayer coating, the performances of SLM samples, such as micro hardness, the thickness and the wear resistance, were significantly improved. The micro hardness of TiN/TiAlN multilayer coating machined specimen is higher than that of TiN/TiAlN multilayer coating SLM specimen. However, the adhesion of TiN/TiAlN multilayer coating machined specimen is less than that of TiN/TiAlN multilayer coating SLM specimen.

The study provides a new post-processing method for SLM 316L specimen to improve the performance of SLM specimens and to enable SLM specimens to be applied in the field of precision mechanical transmission.

The present paper aims to systematically investigate the influence of building orientations (0°, 15°, 30°, 45°, 60°, 75°) and heat treatment processes on the macro-/micro-structural, mechanical and electrochemical behaviors of selective laser melting (SLM) prepared AlSi10Mg alloy parts.

AlSi10Mg samples were produced by the SLM method using standard processing parameters at 0°, 15°, 30°, 45°, 60° and 75° building angles. The effects of building orientations on the physical, mechanical and electrochemical properties of the alloy were investigated.

With the increase in the building orientation from 15° to 75°, the structural defects were found reducing. The effect of step size of inclined geometries was found to significantly influence the mechanical and electrochemical properties of the AlSi10Mg samples. Tensile strength for samples fabricated at lower angles (0°, 15°, 30°) reported a drop of approximately 11% than SLM 0° samples. Moreover, the tensile strength was found to decrease from 412.35 ± 9.568 MPa for the as-built samples to 290.48 ± 12.658 MPa, whereas the fracture strain increases from 3.32 ± 0.56% to 5.6 ± 0.6% when the as-built sample was treated with T6 treatment. This study indicates that the microstructure and mechanical properties of SLM-processed AlSi10Mg alloy can be tailored by a suitable heat treatment or building angle.

Microstructural and mechanical behavior of horizontal or vertically built SLM components have already been demonstrated several times. However, the influence of different building orientations, such as 0°, 15°, 30°, 45°, 60°, 75°, has not been explored in-depth, particularly on corrosion and general mechanical performance. As a result, this work may be of significant relevance to academics and designers, given the varying orientation of internal component of SLM structures.

The purpose of this paper is to obtain high-temperature-resistant material with high density and to conduct microstructural investigations of 3D-printed Ni-based alloy 713C specimens.

High-density specimens of Ni-based alloy 713C were obtained by the optimizing selective laser melting (SLM) process parameters and an X-ray diffraction (XRD) analysis confirmed the occurrence of γ and γ′ phases and the presence of carbides in the SLM-manufactured Ni-based alloy 713C. The analysis of electron backscatter diffraction (EBSD) studies suggested a preferred 〈100〉 direction orientation and low angle misorientation for the SLM specimens.

The high-density specimens of Ni-based alloy 713C were obtained by the optimized SLM process parameters. XRD analysis confirmed the presence of γ and γ′ phases and carbides in the SLM-manufactured Ni-based alloy 713C. Analysis of EBSD studies suggested a preferred 〈100〉 direction orientation and low angle misorientation for the SLM specimen.

In this study, 3D-printed Ni-based alloy 713C with a high density of 99% was obtained for the first time, to the best of the authors’ knowledge.

The present study aims to investigate the effect of finish machining and aging processes on the surface integrity of the selective laser melted (SLM) maraging steel samples and compared them with those obtained conventionally.

Finish machining and aging were applied on the SLM and wrought maraging samples to investigate and compare their microstructural and mechanical properties such as surface roughness, microhardness and wear resistance.

After applying aging and finish machining treatments, the surface roughness <1 µm, microhardness (542Hv) and wear resistance (COF 0.578) of SLM samples were similar to their wrought counterparts. Compared to finish machining, the effect of aging was more significant on the microhardness and the wear resistance, regardless of sample type.

The knowledge of post-processing is essential to enhance the functional performance of the SLM samples. Aging and finish machining were applied for the first time to evaluate the surface integrity of the SLM prepared maraging steel and compared it with the wrought samples.

The purpose of this paper is to examine the effect of internal pores on the tensile properties of a Co–Cr–Mo alloy fabricated by selective laser melting (SLM).

The size and volume fraction of pores were controlled through high temperature annealing (HTA) and hot isostatic pressing (HIP).

After HTA, the size and fraction of pores decreased compared with the as-built SLM sample, and no pores were observed after HIP. Tensile tests of the HTA and HIP samples showed nearly similar tensile deformation behavior. From the results, the authors found that the size of the internal pores formed in the SLM process had little effect on the tensile properties. The as-built SLM sample had less elongation than the HTA and HIP samples, which would not the effect of porosity, but rather the effect of the residual stress and the retained ε phase after the SLM process.

Although pores are a main factor that influence the mechanical properties, the effect of pores on the tensile properties of Co–Cr–Mo alloys fabricated by SLM has not been studied. Therefore, in this study, the effect of pores on the tensile properties of a Co–Cr–Mo alloy fabricated by SLM was studied.

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.

In this paper, the mechanical properties and corrosion resistance of CoCr alloy fabricated by selective laser melting (SLM) were studied, and the changes of performance after porcelain sintering process were also analysed. This study is to point out the relationship between the microstructure, mechanical properties and corrosion resistance of CoCr alloys prepared by SLM after porcelain sintering process. In addition, the biosafety of the sintered CoCr alloy was evaluated.

The microscopic feature changes of CoCr alloy samples after porcelain sintering process were observed by DMI 5000 M inverted metallographic microscope and Nova Nano430 FE-SEM. Moreover, phase identification and determination were conducted by X-ray diffraction (XRD) using Smartlab X-ray diffractometer. The Vickers microhardness was measured on the HVS-30 microhardness tester, and tensile tests were carried out on a CM3505 electronic universal testing machine. The corrosion resistance was tested by a classical three-point electrode system electrochemical method, then the ion precipitation was measured by using an atomic absorption spectrometer of Z2000 7JQ8024.

The XRD results indicate that the transition of γ phase (FCC) to e phase (HCP) occurs during the porcelain sintering processing of CoCr alloy. Moreover, the Vickers microhardness of the upper surface and the side surface of the CoCr alloy sample was improved by more than 36%. In addition, the ultimate strength of CoCr alloy via porcelain sintering treatment was increase to 1,395.3 ± 53.0 MPa compared to 1,282.7 ± 10.1 MPa of unprocessed CoCr alloy. However, the corrosion resistance of CoCr alloy samples decreases after porcelain sintering process.

There are few studies on the relationship of microstructure, mechanical properties and corrosion resistance of CoCr alloys prepared by SLM after porcelain sintering process. In this study, the microstructure, mechanical properties and corrosion resistance of CoCr alloy after porcelain sintering process were studied, and the biosafety of the alloy was evaluated. The research found that it is feasible to apply CoCr alloy fabricated by SLM to dental medicine after porcelain sintering process.

This study explains the importance of performance measures and identifies the specific performance measures of sustainable lean manufacturing (SLM) for automobile industries. Awareness towards sustainability and continuous improvement approaches demand monitoring of the sustainable lean impact on organization/industry, and hence, identifying the specific performance metrics is of peak importance.

In this study, specific metrics for social, economic and environmental performance are identified from a systematic literature review of 82 significantly related journal articles. The importance of the identified metrics is assessed with the help of questionnaire responses from a group of industrial experts.

Performance indicators are statistically analyzed category wise and assessed. The key metrics are summarized based on the survey data followed by a discussion with industrial experts. From this study, performance measures have been identified and validated through hypothesis testing for Indian automobile industries. Certification of IATF16949 implementation found an important vertical for SLM implementation. In this study, SLM implementation initiatives are discussed, and reward scheme for outstanding performers are identified as important initiatives are followed by small improvement culture.

The proposed discussion of this study is useful for industrialist and researchers, as SLM performance measures are well explained for Indian automobile industries. In this study, future research direction is also explained related to other industries. These summarized performance measures will help to maintain SLM in industries.

This paper presents the original literature review based on the study of SLM, as no extensive study is available where SLM performance measure explained for automobile industries. Key initiatives and vertical of SLM are well explained for Indian automobile industries. This study proposed a complete framework for SLM implementation considering competitive manufacturing targets.

In recent years, the use of high performing materials, and application of additive manufacturing technology for industrial production has witnessed a steady rise and its expanse is only to increase in the future. “Selective laser melting (SLM) technique” for an exotic nickel-titanium (NiTi) shape memory alloy (SMA) is expected to a great facilitator to research in this area. The purpose of this paper is to put forth the research direction of NiTi shape memory alloy by selective laser melting.

This review also summaries and skims out the information on process equipment, adopted methodologies/strategies, effects of process parameters on important responses e.g. microstructure and comprehensive functional and mechanical properties of SLM-NiTi. In particular, the functional characteristics (i.e. shape memory effects and super-elasticity behavior), process analysis and application status are discussed.

Current progresses and challenges in fabricating NiTi-SMA of SLM technology are presented.

This review is a useful tool for professional and researchers with an interest in the field of SLM of NiTi-SMA.

This review provides a comprehensive review of the publications related to the SLM techniques of NiTi-SMA while highlighting current challenges and methods of solving them.

Selective laser melting (SLM) is an additive manufacturing technology that is gaining industrial and research interest as it can directly fabricate near full density metallic components. The paper aims to identify suitable process parameters for SLM of processing of pure nickel powder and to study the microstructure of such products. The study also aims to characterize the microhardness and tensile properties of pure nickel produced by SLM.

A 2⁴ factorial design experiment was carried out to identify the most significant factors on the resultant porosity of nickel parts. A subsequent experiment was carried out with a laser power of 350 W. The scanning speeds and hatch spacings were varied.

Scanning speed and hatch spacing have significant effects on the porosity of SLM components. A high relative density of 98.9 per cent was achieved, and microhardness of 140 to 160 Hv was obtained from these samples. A tensile strength 452 MPa was obtained.

As the energy input levels were made in steps of 20 J/mm³ for the optimization study, the true optimal combination of parameters may have been missed. Therefore, researchers are encouraged to test the parameters with smaller variations in energy levels.

The paper provides a set of optimized parameters for the SLM of pure nickel. This study enables the three-dimensional (3D) printing of objects with nickel, which has applications in chemical catalyses and in microelectromechanical systems with its magnetostrictive properties.

This research is the first in direct processing of pure nickel using SLM, with the identification of suitable process parameters. The study also provides an understanding of the porosity, microhardness, strength and microstructure of SLM produced nickel parts. This work paves the way for standardization of 3D printed nickel components and enables the applications of pure nickel via SLM.