Effect of laser-induced ultrasound treatment on material structure in laser surface treatment for selective laser melting applications

Ivan A Ivanov,Maxim Yu Anufriev,Anton S Bychkov,Pavel V Chirkov,Stepan L Lomaev,Konstantin E Kuper,Alexander A Karabutov,Artem A Gapeev,Roman M Kichigin,Vladimir V Dremov,Svetlana A Gruzd,Vladimir S Dub,Nikolay N Simakov,Igor A Kudinov,Elena B Cherepetskaya,Alexey V Karavaev,Mikhail D Krivilyov

doi:10.1038/s41598-021-02895-8

Abstract

A new mechanism for controlling the microstructure of products in manufacturing processes based on selective laser melting is proposed. The mechanism relies on generation of high-intensity ultrasonic waves in the melt pool by complex intensity-modulated laser irradiation. The experimental study and numerical modeling suggest that this control mechanism is technically feasible and can be effectively integrated into the design of modern selective laser melting machines.

Highlights

A new mechanism for controlling the microstructure of products in manufacturing processes based on selective laser melting is proposed
Despite the variety of Additive manufacturing (AM) process, including selective laser melting (SLM)[1,2,3], direct laser metal deposition[4,5,6], electron beam m elting[7,8] and o thers[9,10], the manufactured parts may contain imperfections. This is primarily due to the specific features of the melt pool solidification process associated with high thermal gradients, high cooling rates, and the complexity of heating cycles in the melted and re-melted m aterial[11], which lead to epitaxial grain growth and significant porosity[12,13]
Grain refinement of the microstructure by several times was observed during laser-based direct energy deposition of Ti-6Al-4V26,33 alloy, nickel-based superalloy Inconel 62526 and 316L stainless steel[34] with an external high-intensity ultrasound source attached to the substrate

Summary

Introduction

A new mechanism for controlling the microstructure of products in manufacturing processes based on selective laser melting is proposed. Despite the variety of AM process, including selective laser melting (SLM)[1,2,3], direct laser metal deposition[4,5,6], electron beam m elting[7,8] and o thers[9,10], the manufactured parts may contain imperfections This is primarily due to the specific features of the melt pool solidification process associated with high thermal gradients, high cooling rates, and the complexity of heating cycles in the melted and re-melted m aterial[11], which lead to epitaxial grain growth and significant porosity[12,13]. Laser surface treatment of each layer is equivalent to “laser volume treatment” if the part is constructed layer by layer

Methods

Results

Conclusion