Papers by Keyword: Layer Thickness

Abstract: Additive manufacturing by laser powder bed fusion (LPBF) is increasingly applied to aluminium alloys; however, the resulting surface quality and machining behaviour remain critical challenges, particularly when post-processing is required. In this context, the interaction between LPBF process parameters and advanced cooling strategies during machining remains largely unexplored.This study examines the impact of cryogenic machining on the surface integrity of LPBF-produced AlSi7Mg components, fabricated with varying layer thicknesses. Specimens were machined under fixed cutting parameters using either conventional flood cooling or cryogenic cooling. Cutting forces, surface roughness, defect morphology, and subsurface microstructure were systematically evaluated.Cryogenic cooling consistently reduced cutting forces and improved surface quality, effectively suppressing tearing formation. In contrast, under flood cooling, the influence of the microstructural differences induced by layer thickness remained significant, with increasing LPBF layer thickness further enhancing both surface and subsurface integrity. Overall, the results reveal a strong interaction between LPBF parameters and cooling strategy, highlighting the unexpectedly beneficial role of cryogenic machining in improving the surface integrity of LPBF-processed AlSi7Mg alloys.

Abstract: Additive Manufacturing (AM) is growing much faster because of its capability to produce complex geometries accurately without material wastage, using a CAD 3D model. It has immense scope in sectors such as aerospace, healthcare, filtration, mechanical, and electrical industries. Out of the many AM technologies available, Stereolithography (SLA) is one process that can build prototypes and end-use products using resins. SLA is particularly known for producing smooth surfaces with tight dimensional tolerances. Several SLA process parameters play a crucial role in producing dimensionally accurate parts. This study focuses on the impact of layer thickness, exposure time, print orientation, and curing time on the dimensional accuracy of SLA-printed parts. A Taguchi-based array was used to design and conduct the experimental work, and the analysis was carried out using Analysis of Means (AOM) plots and regression equations. The optimal settings improved precision, with a 0° orientation yielding the best results for the inside diameter, and 45° and 90° orientations performing best for outside dimensions. Proper curing time was also found to prevent dimensional errors. A validated prediction model showed minimal errors, thereby enhancing the accuracy of SLA-printed parts. These findings show that by optimizing layer thickness, exposure time, print orientation, and curing time, SLA printing can consistently achieve high dimensional accuracy. Such improvements make SLA more viable for industrial applications requiring precision, such as aerospace components, custom medical devices, and high-performance mechanical parts

Abstract: Additive Manufacturing (AM), or as it is often called 3D printing, is the process of making objects by adding successive thin layers of material. One of the AM methods used is Digital Light Processing (DLP), which is a 3D printing technology that uses photopolymer resin (also known as UV Resin) as a manufacturing material. In the resin 3D printing process, several problems arise, such as the degree of drying which depends on the length of drying time and the difference in layer thickness which affects the material properties. Therefore, it is necessary to analyze how printing thickness parameter and drying (post-curing) time affect material properties, especially in terms of tensile strength values. This study used a variety of specimens, such as post-curing times of 90 minutes, 120 minutes, and 150 minutes with a layer thickness of 0.050 mm, as well as variations in layer thickness of 0.050 mm, 0.075 mm and 0.100 mm with a post-curing time of 150 minutes. Each specimen is printed and tested according to ASTM D638 standard. The results showed that the tensile strength values increased with increasing in post-curing time, and conversely, the tensile strength values decreased with increasing layer thickness. The longest post-curing time of 150 minutes and the thinnest layer thickness of 0.050 mm produce the highest tensile strength of 24.9 MPa.

Abstract: The technological advancements in laser powder bed fusion (PBF-LB/ L-PBF) processing has led to the potential in utilizing larger powder bed layer thicknesses aimed at increasing the productivity. Moreover, by increasing the layer thickness, coarser powder particle size distribution (PSD) may be employed, further improving cost-effectiveness of the process. This drives the shift towards a more sustainable process chain, while reinforcing the business cases in additive manufacturing (AM). In this study, the effect of larger layer thickness (i.e., 90 µm) using recommended PSD of 15 to 45 µm, as well as feedstock powder with a coarser PSD (i.e., 45 to 90 µm) on the surface characteristics, heat treated microstructure, and mechanical properties of Ti64 components is evaluated. The results were then compared with that of 30 and 60 µm layer thicknesses, using a standard PSD of 15 to 45 µm.

Abstract: In the current era of additive manufacturing, Fused Deposition Modelling (FDM) method of printing is being studied extensively to print a concept model. Therefore, the dimensional accuracy and the mechanical properties of the FDM 3D printed part are very important. In this study, the tensile specimens are prepared according to ASTM D638 Type I. Dimensions of the specimen is measured in the x-direction (length), y-direction (width), and z-direction (height) and is compared against the standard measurement for accuracy. Tensile stress, strain at break and Young’s modulus were also investigated. Overall, the dimension accuracy achieved is more than 98%. The highest accuracy is obtained by using 0.2mm layer thickness and 0.2mm initial layer thickness. The tensile stress, Young’s modulus and strain at break are found to decrease when the layer thickness is increased. This is due having more layer with lesser and smaller voids which increases the strength and stiffness. Increasing initial layer thickness, however, has a low influence on the tensile stress but can greatly affect the Young’s modulus.

Abstract: In this research, the thickness of coating layer and hardness of coated 316L stainless steel surface has been improved by Quench Polish Quench (QPQ) coating process. The influences of nitriding Temperature(T), nitriding time(t_c), and Oxidation time(t_o) on hardness and thickness of coated surface have also been investigated using Taguchi method. During this process, the percentage of carbonate and cyanate, post oxidation temperature, and time are constantly maintained. The experimental investigations have been performed using the Taguchi analysis to examine the effects and to predict the combination of optimum processing time settings. The nitriding time and temperature are significantly contributed to the hardness and maximizing the thickness respectively. The level-3 of all process parameters has been recommended to maximize the hardness (800 Hv) and layer thickness (19.6 µm). The microstructure of the Layer thickness on the coated stainless-steel surface has been illustrated using a Scanning Electron Microscope (SEM) image.

Abstract: In the context of Industry 4.0, the interest towards the additive manufacturing processes is growing due to their numerous advantages, such as the possibility to prototype, the reduction of waste material, the inferior time to market, ad so on. In particular, a promising technology is the Direct Laser Deposition, which uses a focused laser beam to melt powders as there are deposited. In opposition to the well-established powder-bed fusion technologies, there are still some issues related to this process. This work aims to solve one of them, exploring the potentialities of DLD in printing thin-wall structures. For this purpose, the influence of the adopted deposition strategy and of the layer thickness on the geometrical accuracy and mechanical properties has been investigated. The results have pointed out that the first variable strongly influences the workpiece. It is possible to deposit thin-wall structures with a ZigZag strategy and consider a layer thickness equal to 90% of the height of the single track, printed with the same process parameters.

Abstract: Surface roughness of ABS material on FDM process due to different orientation angle and layer thickness are investigated using an experimental method. The aim of this paper is to determine the effect of orientation angle and layer thickness on surface roughness on 3-dimension FDM printing on ABS material. A rectangle model with 60 mm length,10 mm in width, and 10 mm in height is used in this research. The orientation angle of model is 30, 45, and 60 degrees in layer thickness of 0.15 mm and 0.25 mm. The results indicates that the different orientation angle of the layer thickness causes the roughness value of the printed surface. The roughness surface value increases along with increasing of the orientation angle. The highest surface roughness value occurs at 60 degrees orientation angle in 0.15 mm layer thickness.

Abstract: The 3D printed cubic bulk specimens (10x10x10 mm) were fabricated by Selective Laser Melting (SLM) additive manufacturing (AM) technology from TiAl6V4 powder, using different layer thickness (from 40 to 60 μm), for investigation of the influence of layer thickness on microstructure of SLM-fabricated TiAl6V4.

Abstract: Selective laser melting (SLM) is an additive manufacturing technology that allows to produce functional parts with extremely complex shape from metal powder feedstock. 240 single tracks with the length of 10 mm were fabricated using different SLM process parameters: laser power output, powder layer thickness, point distance and exposure time. Obtained single tracks were measured using optical microscopy. An influence of SLM process parameters on geometrical characteristics of obtained single tracks was investigated.