Microstructures and mechanical properties of Fe-Cr stainless steel parts fabricated by ultrasonic vibration-assisted laser engineered net shaping process

• Fe-Cr parts were fabricated by ultrasonic vibration-assisted LENS process.
• Porosity, micro-cracks, and grain size of the fabricated parts were decreased.
• Tensile properties and microhardness of the fabricated parts were improved.
• Ultrasonic vibration is beneficial to refine microstructure and improve property.

This paper studied fabrication of Fe-Cr stainless steel parts using the novel ultrasonic vibration-assisted laser engineered net shaping (UV-A LENS) process and investigated the effects of ultrasonic vibration on the microstructures and mechanical properties. The results showed that cross-sectional morphology as well as internal microstructure of the parts were changed by applying ultrasonic vibration in LENS process. Porosity, micro-cracks, and microstructural grain size were remarkably decreased due to the actions and influences of ultrasonic vibration. In addition, mechanical properties of the parts fabricated by UV-A LENS process were significantly improved compared with that of the parts fabricated by LENS without ultrasonic vibration. These findings indicated that UV-A LENS was an effective process to generate uniform morphology and fine microstructures to improve the mechanical properties of the parts.