Showing papers in "Journal of Materials Processing Technology in 2018"

TL;DR: In this paper, an experimental analysis of spatter formation was carried out on an instrumented SLM set-up allowing the quantification of spatiotemporal ejections and possible correlation with melt-pool behavior.

TL;DR: In this paper, a wire arc additive manufacturing of AA5183 aluminium alloy using conventional gas metal arc welding deposition on 20"mm thick AA6082-T6 plate as support material is presented.

TL;DR: In this paper, an innovative wire arc additive manufacturing (WAAM) process with forced interpass cooling using compressed CO2 was employed to fabricate Ti6Al4V thin-walled structures.

TL;DR: In this paper, a simple thermal model of selective laser melting (SLM) process is evaluated and the temperature distribution in the sample is characterized by two dimensionless parameters: normalized enthalpy and the ratio of dwell time to the thermal diffusion time.

TL;DR: In this paper, a methodology based on a laser vision system was proposed to view the surface appearance on the side face of multi-layer single-pass low-carbon steel parts deposited in GMAW-based additive manufacturing, and a corresponding evaluation method was established to quantify the surface roughness.

TL;DR: In this article, a double-wire+arc additive manufacturing system was built to add magnesium into Al-Cu deposits for higher mechanical properties, and the microstructure and morphology of thin wall samples were characterized by optical micrographs, X-ray diffraction (XRD) and scanning electron microscopy (SEM).

TL;DR: In this paper, the X40CrMoV5-1 (H13) hot work tool steel was densified by selective laser melting (SLM) using different laser parameters and preheating temperatures.

TL;DR: In this paper, a three dimensional selective laser melting process simulation is developed to investigate the melt-pool behavior of a randomly-distributed powder bed with keyhole formation by Nd-YAG laser.

TL;DR: Porosity was measured for 21 AA2319 wire and arc additive manufacture (WAAM) panels built using different wire batches, cold metal transfer (CMT) modes, wire feed speed (WFS) and travel speed (TS) as mentioned in this paper.

TL;DR: In this paper, a simulation model was developed to enhance understanding of the manufacturability of these new materials, as well as to predict the temperature evolution and thermal behaviors of the molten pool under various volumetric laser energy densities.

TL;DR: In this paper, an innovative finishing technique combining chemical and abrasive flow polishing of interior surfaces of tubular IN625 components designed for the aerospace industry was designed and validated, and the synergistic effect stemming from a combined use of the chemical-abrasive flows was investigated by studying: a) the flow of abrasive particles suspended in water, b) a flow of a chemical solution without abrasives, and c) the surface roughness and texture.

TL;DR: In this paper, the effect of changing scanning speed on the formation of single track, as well as the overlapping rate to form multi tracks during SLM processed (SLMed) Al-Cu-Mg alloy was investigated.

TL;DR: In this article, a new volumetric heat source was proposed to estimate the size of the melt pool cross-section during Selective Laser Melting (SLM), which takes into account the effect of powder size distribution on the propagation of the laser energy through the depth of the metal powder layer.

TL;DR: In this paper, the authors investigate the fatigue behavior of additively manufactured (AM) NiTi (i.e., Nitinol) specimens and compare the results to the wrought material.

TL;DR: In this article, the authors developed an enhanced BOM (E.BOM) for wire and arc additive manufacturing (WAAM), which takes the spreading of the weld beads into consideration.

TL;DR: In this paper, a tapered thread tool with triple facets was designed and tested for high depth-to-width ratio friction stir welding at a rotational speed of 800-rpm and a welding speed of 30mm/min.

TL;DR: In this article, a method to reduce the surface roughness of Cobalt Chromium (CoCr) components with complex surface geometry by using a layered polishing method which can constantly adjust the defocusing distance of the laser along with the surface shape of the components.

TL;DR: In this article, a sound hybrid joint was achieved with a sufficient mixture of 6061-T6 aluminum alloy and polyether ether ketone (PEEK) via friction stir lap welding (FSLW) by a tapered thread pin with the triple facets.

TL;DR: In this article, an improved method of selective laser melting with parameters of two process windows for each of the laser beam spots is presented, which can give a possibility to obtain 3D-object with the parameters up to 1'kW for laser source power and up to 0.3'm/s for scanning speed.

TL;DR: In this article, the effect of the laser power density and focus size on the residual stress field of an AA2198-T8 has been investigated using the finite element method.

TL;DR: In this article, the effect of processing parameters on densification behavior during selective laser melting (SLM) of pure Zn, and obtain high density in a reasonable process window was investigated.

TL;DR: In this article, the effects of duplex coolant jets on chip-tool interface temperature were studied, and the mean surface roughness, cutting force, tool wear and chip formation were analyzed at varying cutting speed and feed rate combinations.

TL;DR: In this article, seven sets of rivet and die combinations with different die-to-rivet volume ratios were selected to investigate the effects of four key factors, i.e., rivet hardness, rivet length, die width and die pip height, on the rivetability and mechanical performance of the aluminum alloy AA6061-T6 and mild steel CR4.

TL;DR: A preliminary investigation was carried out into the application of angularly exerted ultrasonic vibrations in friction stir welding for the joining of AA 6061-T4 alloy to AZ31B at different tool rotation speeds as mentioned in this paper.

TL;DR: The instability of the keyhole and bubble being captured by solidification interface are the main factors that affect the formation of porosity in laser welding of both aluminum alloy and steel as discussed by the authors.

TL;DR: In this article, the fabrication of line-like and pillar-like periodic microstructures on stainless steel by means of direct laser interference patterning was studied, where a picosecond (10-ps) pulsed Nd:YAG laser operating at 1064-nm wavelength was used to produce the micro-structures with spatial periods ranging from 2.6μm to 5.2μm.

TL;DR: In this article, the influence of ultrasonic vibration on the plasticity of lightweight metals (aluminium and titanium) was investigated by means of Ultrasonic assisted compression (UAC) experiments, which was carried out based on the newly designed ultrasonic horns and transducers which can generate a series of vibration frequencies (20, 30 and 40 kHz) and adjustable vibration amplitudes (4.06-10.37μm).

TL;DR: In this paper, a new technology was developed to improve the anti-friction performance of cutting tools by constructing textured surface with composite lyophilic/lyophobic wettabilities and applied to polycrystalline diamond (PCD) tools.

TL;DR: In this paper, a multiscale model is developed to investigate the evolution mechanisms of site-specific grain structures during additive manufacturing of metallic alloys, using the selective electron beam melting (SEBM) fabrication of Ti-6Al-4V as an example.

TL;DR: In this paper, a finite element model is developed to calculate the heat propagation of a circular thin-walled component fabricated in gas metal arc welding based additive manufacturing, and the heat evolution, thermal cycle feature, and temperature gradient in molten pool and deposited layers are revealed.