Effect of Laser Power on Microstructure and Mechanical Properties of Laser Welded High-Nitrogen Steel

Wang, Meirong; Dong, Jianlin; Yang, Haifeng; Wang, Wujun; Chen, Yu; Zhu, Xinnan; Fu, Yue

doi:10.3390/met16030261

This is an early access version, the complete PDF, HTML, and XML versions will be available soon.

Open AccessArticle

Effect of Laser Power on Microstructure and Mechanical Properties of Laser Welded High-Nitrogen Steel

by

Meirong Wang

^1,2,

Jianlin Dong

^1,2,3,

Haifeng Yang

^1,2,*,

Wujun Wang

^1,2,

Yu Chen

^1,2,

Xinnan Zhu

^1,2 and

Yue Fu

^1,2

¹

State Key Laboratory of Precision Welding & Joining of Materials and Structures, Harbin Institute of Technology, Harbin 150001, China

²

Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology, Weihai 264209, China

³

School of Materials Science and Chemical Engineering, Harbin University of Science and Technology, Harbin 150040, China

^*

Author to whom correspondence should be addressed.

Metals 2026, 16(3), 261; https://doi.org/10.3390/met16030261

Submission received: 1 February 2026 / Revised: 21 February 2026 / Accepted: 24 February 2026 / Published: 26 February 2026

(This article belongs to the Special Issue Novel Insights into Welding and Joining Technologies of Metallic Materials)

Download Versions Notes

Abstract

This study investigates the influence of laser welding process parameters on the weld bead formation, microstructure, and mechanical properties of high-nitrogen steel. Results indicate that as laser power increases, the weld bead width expands, while the cross-sectional porosity exhibits a trend of initially decreasing and then increasing. The lowest porosity is achieved at a power of 2.1 kW and a welding speed of 8 mm/s. Microstructural analysis revealed that higher laser power promotes grain coarsening, increases the proportion of high-angle grain boundaries, and raises the ferrite phase content. At 2.4 kW, the weld zone exhibits high dislocation density and significant lattice distortion. Regarding mechanical properties, the hardness of the weld metal gradually decreased with increasing laser power, while the tensile strength exhibited an initial increase followed by a decrease. The tensile strength (840.5 MPa) was also achieved under the process conditions of 2.1 kW and 8 mm/s.

Keywords: high-nitrogen steel; laser welding; microstructure; mechanical properties

Share and Cite

MDPI and ACS Style

Wang, M.; Dong, J.; Yang, H.; Wang, W.; Chen, Y.; Zhu, X.; Fu, Y. Effect of Laser Power on Microstructure and Mechanical Properties of Laser Welded High-Nitrogen Steel. Metals 2026, 16, 261. https://doi.org/10.3390/met16030261

AMA Style

Wang M, Dong J, Yang H, Wang W, Chen Y, Zhu X, Fu Y. Effect of Laser Power on Microstructure and Mechanical Properties of Laser Welded High-Nitrogen Steel. Metals. 2026; 16(3):261. https://doi.org/10.3390/met16030261

Chicago/Turabian Style

Wang, Meirong, Jianlin Dong, Haifeng Yang, Wujun Wang, Yu Chen, Xinnan Zhu, and Yue Fu. 2026. "Effect of Laser Power on Microstructure and Mechanical Properties of Laser Welded High-Nitrogen Steel" Metals 16, no. 3: 261. https://doi.org/10.3390/met16030261

APA Style

Wang, M., Dong, J., Yang, H., Wang, W., Chen, Y., Zhu, X., & Fu, Y. (2026). Effect of Laser Power on Microstructure and Mechanical Properties of Laser Welded High-Nitrogen Steel. Metals, 16(3), 261. https://doi.org/10.3390/met16030261

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Menu

Effect of Laser Power on Microstructure and Mechanical Properties of Laser Welded High-Nitrogen Steel

Abstract

Share and Cite

Article Metrics

Article Access Statistics

Further Information

Guidelines

MDPI Initiatives

Follow MDPI