Effect of process parameters on the formation of laser-induced nanoparticles during material processing with continuous solid-state lasers

Abstract

Articles you may be interested inEffect of process parameters in laser cladding on substrate melted areas and the substrate melted shape J. Laser Appl. 27, S29201 (2015); 10.2351/1.4906376 Effect of laser and laser hybrid welding on the corrosion performance of a lean duplex stainless steel J. Laser Appl. 22, 150 (2010); 10.2351/1.3533146 Visualization of refraction and attenuation of near-infrared laser beam due to laser-induced plume J. Laser Appl. 21, 96 (2009); 10.2351/1.3110058Interaction between laser beam, process effects, and structural properties during welding using models based on the finite element analysis During laser material processing with high laser beam intensities, a laser-induced vapor formation can occur. Due to the shockwave behavior of the vapor plume and the associated rapid cooling, a significant particle formation can be initiated by nucleation. The laser radiation interacts with the particles which can result in a dynamic change of the intensity distribution on the surface. Especially in the field of laser remote processing, the attenuation of laser radiation by nanoparticles can influence the process stability and reduce the processing quality. The presented work is focused on the particle formation at a height of 10 mm above the material surface during the laser welding of stainless steel with a fiber laser. The laser beam intensity on the surface was varied between 1.3 and 5.1 MW/cm 2 . Transmission electron microscopy images of the nanoparticles and high speed images of the vapor propagation in the ambient atmosphere were analyzed. The attenuation of a probe beam in the vapor plume was evaluated in dependence on the wavelength. The results indicate a linear connection between the laser beam power and the particle formation rate. V C 2015 Laser Institute of America. [http://dx.

Texture control of 316L parts by modulation of the melt pool morphology in selective laser melting

“…They collected less spattered powder for manufactured at low shielding gas flow, likely indicating an interaction between the laser and those particles and resulting in lower mechanical performances due to incomplete melting. In the same manner, Scholz et al (2015) observed that the laser power can be locally attenuated by the metal vapor plume. This vapor plume can interact in two ways with the laser beam: directly and indirectly.…”

Laser-Welded Steel Foils with Sapphire Substrates

“…In Ref. [21], it was reported that liquid drops of the stainless steel with a size in the lower nanometer range can be formed in the vapor plume, leading to nanoparticles after the cooling.…”

“…One of the possible applications would be the production of electrically conducting steel structures on sapphire substrates. Laser welding of the stainless steel with transparent materials, like polymers [19] and sapphire, has been reported only in a few works [20,21]. In the latter references, a picosecond pulsed laser and a continuous-wave laser were used, respectively.…”

“…In the latter references, a picosecond pulsed laser and a continuous-wave laser were used, respectively. The effect of laser irradiation on stainless steel plate and the subsequent formation of nanoparticles were reported [21].…”

Nondiffractive beam shaping for enhanced optothermal control in metal additive manufacturing

“…To this end, our work demonstrates that Bessel beams are the ideal replacement to conventional diffractive beam shapes due to their relatively greater degree of propagation invariance, thereby alleviating the need for the integration of adaptive optics for focal and aberration compensation ( 31 , 35 , 44 ), which presents unfeasible logistic complications by adding to the design complexity of AM machines. In addition, it has been proposed that at high energy densities, strong plume-laser interactions and the interaction of the laser beam with ejected nanoparticles could attenuate the power delivered to the build surface ( 39 , 45 ). Although we have not explicitly studied such interactions in the present work, crude evidence of this can be garnered from Fig.…”