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A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study aims to investigate its characteristics of laser sintering and get the optimal process parameters.

The effect of mass ratio of co-PA-PES on thermal behavior was analyzed using a simultaneous thermal analyzer, and the density and mechanical properties of sintered parts were tested to evaluate the performance of the polymeric system. Scanning electron microscopy and Fourier transform infrared spectroscopy were performed to characterize the microstructure and binding mechanism of sintered co-PA-PES parts. Specifically, mechanical properties of the mixture with 20 Wt.% PA-B249 were optimized based on a design of experiment methodology, along with the restriction of maximum absorbable laser energy density.

Liquid phase fusion was considered as the main sintering mechanism for co-PA-PES, and mechanical interlocking was the dominant binding mechanism. The effects of mass ratios of this material on the thermal properties, density and mechanical properties were obtained via data results. Additionally, compared to neat PES-HmA, co-20 Wt.% PA-PES showed a 71.7 per cent increase in tensile strength, 24.4 per cent increase in flexural strength and 102.1per cent increase in impact strength.

This paper proposed a new kind of polymer mixture as the feedstock for laser sintering with the advantages of low price and easy processing. The filler of PA-B249 effectively improved the performance of the polymer mixture, including but not limited to mechanical properties.

A pine/co-PES composite (PCPES composite) was proposed as the feedstock for powder bed fusion (laser sintering, LS). This paper aims to provide some necessary experimental data and the theoretical foundation for LS of pine/co-PES, especially for the application of using the laser-sintered pine/co-PES parts as complex structural patterns in investment casting.

The PCPES composites with different pine loadings were mixed mechanically. The composite’s preheating temperature and processing temperature during LS were determined experimentally based on the material’s thermal behavior. The effects of pine powder on the binding mechanism of PCPES composites were discussed through analyzing the microstructure of the laser-sintered parts’. Mechanical properties and dimensional precision of laser-sintered PCPES parts in different pine loadings were tested, and the parts’ mechanical properties were strengthened by wax-infiltration post-processing. The influence extents of process parameters on the mechanical properties of laser-sintered 20 Wt.% pine/co-PES parts were investigated using a 1/2 fractional factorials experiment.

20 Wt.% pine/co-PES is considered to be a promising wood-plastic composite for laser sintering. The relationship between mechanical strength of its laser-sintered parts and process parameters was built up using mathematical formulas. Experimental results show density, tensile strength, flexural strength and surface roughness of laser-sintered 20 Wt.% pine/co-PES parts are improved by 72.7-75.0%, 21.9-111.3%, 26.8-86.2%, 27.0-29.1% after post-process infiltration with a wax. A promising application of the wax-infiltrated laser-sintered parts is for investment casting cores and patterns.

The proper process parameters and forming properties of laser-sintered parts are limited to the results of laser sintering experiments carried on using AFS 360 rapid prototyping device.

This investigation not only provides a new feedstock for laser sintering with the advantages of low cost and fabricability but also uses an advanced technique to produce personalized wood-plastic parts efficiently. Mathematical models between mechanical properties of laser-sintered PCPES parts and LS process parameters will guide the further LS experiments using the 20 Wt.% pine/co-PES composite. Besides, the laser-sintered PCPES parts after wax-infiltration post-processing are promising as complex structural patterns for use in investment casting.

The purpose of this paper is to improve the quality of additive manufactured optically translucent parts by investigating the manufacturing issues, analyzing lithophane production criteria and identifying the best translucent material and additive manufacturing (AM) technology.

Figured lithophanes were laser sintered on a 3D Systems SinterStation® HiQ™ with varying layer thickness and plate thickness. Laser sintered (LS) polyamide (PA) 12 blanks were cyanoacrylate infiltrated and polished. Optical properties and performance were compared with the original LS blanks. Lithophanes and blanks were manufactured using 3D systems stereo lithography apparatus (SLA)® Viper ™si2 station, and optical properties and lithophane performance were compared with the LS specimens.

When building in the XY plane, it is optimal to sinter with the minimum layer thickness (0.076 mm) and maximum plate thickness (5 mm). Cyanoacrylate infiltration and polishing assists in reducing the LS PA 12 plate surface roughness, but polishing does not affect the lithophane performance. The best LS candidate should have an absorption coefficient of 0.5/mm using a white light source. Improved resolution but reduced contrast was observed on stereolithography (SL) specimens compared to LS parts.

Transmittance experiments were performed on three SL parts which was not sufficient for optical property calculation. Limited literature was found for new material exploration.

It is the first effort to study systematically quality improvement issues of LS PA optically translucent parts. A comparison is made of optical performance between parts made using LS and SL.

The purpose of this paper is to establish a scientific understanding for electrochemical infiltration of laser sintered (LS) preforms.

Electrochemical deposition techniques were modified to induce infiltration of nickel ions inside porous LS structures with deposition on pore walls.

This novel process is feasible and has the potential to produce fully dense parts. Both conductive and non‐conductive preforms can be infiltrated by this method.

Removal of trapped fluids and gases inside the porous structure is one of the major challenges in the described electrochemical infiltration process.

This work enables low‐cost production of structural parts. It expands the application base for additive manufacturing, especially laser sintering technology.

The novel process carried out in this research is energy efficient when compared to state‐of‐the‐art vacuum‐melt infiltration.

The proposed process is a novel method for facilitating room‐temperature infiltration of porous LS preforms.

The purpose of this paper is to develop a methodology to achieve successful infiltration of indirect selective laser sintered steel components with ferrous alloys and thereby to produce fully ferrous components with desirable properties while preserving part geometry.

The approach is to generate a “green” part by selective laser sintering (SLS) of ferrous powder mixed with a transient binder in a commercial polymer machine. This part is post‐processed to burn off the transient binder (brown part) and to infiltrate the porous structure with a lower melting point ferrous metal. A critical consideration is loss of part structural integrity by over‐melting after infiltration as a result of chemical diffusion of alloying elements, principally carbon. A predictive model defining the degree of success of infiltration based on chemical equilibrium may be used to select the temperature for infiltration.

The infiltration temperature should be set such that the equilibrium solid fraction of the final infiltrated part is at least equal to or greater than the brown part solid fraction.

Infiltration temperature must be carefully controlled to prevent melting of the brown part. Effect of alloying elements other than carbon on equilibrium solid fraction is not considered while constructing the predictive model.

This approach can be used to obtain fully ferrous parts with complex geometry and desirable properties using a low‐cost polymer SLS machine.

Considers efforts to date to produce parts by direct selective laser sintering (SLS) of metals, including post processing to improve structural integrity and/or to induce a transformation. Provides a brief overview of the basic principles of SLS machine operation, and discusses materials issues affecting direct SLS of metals and the resultant properties and microstructures of the parts. Reviews results of past efforts on SLS of metal systems such as Cu‐Sn, Cu‐Solder (Pb‐Sn), Ni‐Sn, pre‐alloyed bronze (Cu‐Sn). Finally discusses more recent efforts on SLS of bronze‐nickel powder mixtures in greater detail.

This paper aims to analyze the additive manufacturing orientation effect of laser sintered polyamide 12 (PA 12) optically translucent parts.

Plates with small features, wedges and lithophanes were laser sintered on a SinterStation HiQ™ in different orientations using PA 12. Lithophane performance was assessed using a Picker 240050 X-ray view/light box. All parts were examined using stereomicroscopy to capture the small features.

The quality of the lithophane image was substantially improved by orienting the flat plate side to the incident backlit light. Sintering in the ZX/ZY plane significantly increased the contrast and resolution compared to sintering in the XY plane. The thinnest feature thickness possible in the SinterStation HiQ is in the XY plane 0.13 mm, and it is 0.57 mm when manufacturing in the ZX/ZY plane.

The laser spot size and other machine parameters were not changeable, which limited the manufacturing resolution. Oblique, non-orthogonal orientations were not investigated.

This is a first effort to investigate the manufacturing orientation effect of laser sintered polyamide optically translucent parts. The manufacturing resolutions on different planes were defined.