Work

The Role of Element Segregation in the Fracture Mechanism and Performance of Spot-Welded AlSi7MnMg Aluminum Alloy Joints

Year: 2026

Type: article

Abstract: MnMg alloy, with particular focus on the influence of element segregation and secondary phase behavior on fracture mechanisms and the process window. The results indicate that the weld nugget exhibits a typical dual structure consisting of columnar and equiaxed grain zones, with a corresponding "M"-shaped microhardness profile. Significant segregation of Si, Fe, and Mn elements at the nugget boundary was observed, leading to the formation of low-melting-point eutectic regions and secondary phase bands. These features induce microporosity along segregation trajectories, serving as crack initiation sites and resulting in a notably narrowed spot welding process window. From the perspective of microstructure and solute behavior during non-equilibrium solidification, this work elucidates the intrinsic mechanisms governing joint performance and process stability in non-heat-treatable die-cast aluminum alloys, providing a theoretical basis for their engineering applications.

Source: Materials

DOI: 10.3390/ma19040747

Authors: Hong Xu, Miao Zhao, Rui Wang, Lijun Han, Xiuming Cheng, You Fang

Institutions: Jilin University, Key Laboratory of Automobile Materials, Ministry of Education, Jilin University, First Automotive Works (China)

Language: English

Topic: Advanced Welding Techniques Analysis

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,137

Funder: Department of Science and Technology of Jilin Province