Work

Research on Microstructure and Mechanical Properties of Ultrasonic-Assisted Gas Metal Arc Welding Additive Manufacturing with High-Nitrogen Steel Welding Wire

Year: 2025

Type: article

Abstract: High-nitrogen steels (HNSs) are valued for their superior mechanical strength and corrosion resistance, making them ideal for high-end industrial applications. However, nitrogen loss during gas metal arc welding additive manufacturing (GMAW-AM) often results in porosity and coarse microstructures, degrading component performance. This study introduces a coaxial ultrasonic-assisted GMAW-AM (U-GMAW-AM) process to mitigate nitrogen loss and refine the microstructure. Welding wires with 0.35 wt.% and 0.70 wt.% nitrogen were used to examine the effects of welding voltage (24.5–30 V) and ultrasonic power (0–2 kW). The results show that a higher voltage increases nitrogen evaporation, with a maximum loss of 0.22% at 30 V. In contrast, ultrasonic assistance reduces nitrogen loss by up to 29.17% for the 0.70 wt.% wire. Microstructural analysis reveals a significant reduction in ferrite and enhanced austenite formation due to better nitrogen retention. Mechanical testing shows that ultrasonic assistance improves tensile strength by 100 MPa (up to 919.1 MPa), elongation by nearly 10%, and hardness uniformity. These findings highlight the potential of ultrasonic assistance for optimizing high-nitrogen steel properties in additive manufacturing.

Source: Metals

DOI: 10.3390/met15050491

Authors: Jiawen Luo, Zhizheng He, Zihuan Hua, Chenglei Fan

Institution: Harbin Institute of Technology

Language: English

Topic: Additive Manufacturing Materials and Processes

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,137

Funder: Taishan Industry Leading Talents