Effect of laser contour scan parameters on fatigue performance of A20X fabricated by laser powder bed fusion

Laser contour scanning was used to improve the surface finish and fatigue properties of A20X components produced by laser powder bed fusion. The effects of four different contour laser scan speeds and three different offset distances were evaluated using mechanical testing and advanced characterization. The maximum profile valley depth (Rv) improves by 50.5 % when laser scan speed decreases from 850 mm/s to 350 mm/s, resulting in fatigue life improvement by 200%. The laser contour parameters affect the type and number of pores created close to the surface of the specimens. However, subsurface pores do not affect fatigue life since a fully surfacedriven failure mechanism was observed in this study.

Automated summary

Laser contour scanning improves the surface finish and fatigue properties of A20X components produced by laser powder bed fusion. The study evaluated the effects of different contour laser scan speeds and offset distances on mechanical properties and surface characteristics. Decreasing the laser scan speed from 850 mm/s to 350 mm/s resulted in a 50.5% improvement in maximum profile valley depth (Rv) and a 200% improvement in fatigue life. The type and number of pores near the surface were influenced by the laser contour parameters, but subsurface pores did not affect fatigue life.