The effect of laser power and scanning speed on forming structure in selective laser melting process

Abstract

With the continuous development of ship technology, the usage environment of some parts has changed, with higher requirements for materials and preparation technology being put forward. Some traditional structural materials have do not meet the actual working conditions of ships, which necessitates development of new materials and research on their preparation technology. Owing to its high strength and stable mechanical properties at high temperature, molybdenum base alloy is expected to replace nickel base alloy and aluminum base alloy the primary structural material in the development of ships. Under the conventional method, the impurity elements is quite complex and there are limitations in the shape of the formed parts. This experiment uses spherical pure molybdenum powder as raw material. The effects of laser power, powder thickness, scanning speed and scanning distance on the microstructure of formed parts during selective laser melting process were studied and the optimum process parameters were determined. Laser power and scanning speed can seriously affect the quality of the forming parts. In this experiment, by comparing the density and internal holes of the forming parts under different process parameters, the best preparation process for the forming parts was determined: laser power 325 watts, scanning speed 400mm/s, powder thickness 30μm, scanning distance 40μm. Meanwhile, the forming workpiece density is the largest, up to 94.92%.

Influence of energy density on the microstructure and property regulation of additive manufactured pure nickel

“…6 These issues are closely related to surface tension gradients, thermal capillarity, and bubble movement during the shaping process, ultimately significantly affecting the quality, performance, and safety of the formed parts. 7 Therefore, to optimize components performance, it is essential to exercise the precise control over some key parameters, such as laser power, scanning velocity, hatching spacing, and powder layer thickness. 8 Leung et al 9 found that with the increase in laser power, the wetting ability of the molten pool improves, as the scanning velocity increases, the continuous melting track change to interrupted hemi-cylindrical melting track and a series of independent molten beads forms.…”

Determination of Preliminary Operating Intervals of the Power Density for Laser Technological Processes on Copper Samples

“…The application of different laser technologies also leads to different effects on the modified surface properties. Thus, for example, in addition to the power density and the energy density in the processing area, the scanning speed or the laser interaction time have a strong influence on the modification of a metal surface [10] [11] [12]. All these specific features determine the number of advantages of laser surface treatment over conventional treatment methods, such as local heating of the surface without changing the properties of the substrate material, precision, and high speed of work and low cost [13] [14].…”

Copper laser patterning on a flexible substrate using a cost-effective 3D printer

“…However, lowering the flash intensity to mitigate this risk will reduce the sinter quality. Moreover, this method is not a direct patterning method, and an additional patterning process is required before and after Cu sintering.Another promising technique is direct laser sintering [22][23][24][25][26][27] . During focus, the focused beam energy is absorbed by the precursor and induces a localized, transient heating process that results in rapid sintering.…”

“…Another promising technique is direct laser sintering [22][23][24][25][26][27] . During focus, the focused beam energy is absorbed by the precursor and induces a localized, transient heating process that results in rapid sintering.…”