Laser gas assisted treatment of AISI H12 tool steel and corrosion properties

Surface microrelief and hardness of laser hardened and ultrasonically peened AISI D2 tool steel

“…6, 8, Table 4) similar to other SPD methods [2,14,41,42]. It is not surprising, and it is in good agreement with conclusions of a number of works [7,11,31,43,44] studied the effects of different laser treatments. These studies report that the effects of laser treatment on the surface roughness are strictly dependent on the laser intensity, and they can either lower or conversely enlarge the roughness.…”

“…Thus, the laser polishing was shown to cause the maximal roughness reductions when the energy density range was chosen to be sufficient to melt thin surface layer [31], and the reduced roughness of AISI 1045 steel specimens improved their fatigue behavior [44]. Laser gas assisted treatment was also shown to considerably lower the surface roughness of AISI H12 tool steel if the laser pulse intensity was low enough to avoid large scale surface ablation [43].…”

Laser processing of Ti6Al4V alloy: wetting state of surface and environmental dust effects

“…If oxygen is used in the treated section, high temperature exothermic reactions takes place on the surface and the excessive defects sites are created. However, using assisting gases like nitrogen, argon, or helium minimizes this effect and improves the surface tribological and corrosion properties [3, 4]. Hence, using an assisting gas such as nitrogen not only prevents the surface defects but also forms the nitride species, such as metallic nitride compounds, in the treated region while increasing the surface resistance to wear.…”

Thermal fatigue behavior of Mg–9Al–Zn alloy with biomimetic strengthening units processed by laser surface remelting

“…The treated part was melted more rapidly. As laser moved away, the molten metal was solidified and a self-quenching effect occurred [22][23][24]. The heat led to the rapid heating and cooling of the treatment process, directly contributing to the microstructural modification of the treated area.…”