Research on Microstructures and Mechanical Properties of Fiber Laser Welding of A7N01 Al-Alloy

Abstract:

A7N01 aluminum alloy with the thickness of 10mm is welded using fiber laser with filler wire, the microstructures and mechanical properties of the welding joints are observed and analyzed by microhardness and tensile testers, SEM. The results show that the crystalline morphology of the welding metal is equiaxial as-cast. the columnar crystals exist in the fusion zone next to the weld interface. A softening zone with the width of 1.6 mm is formed in the heat affected zone. Micro-hardness of the welding joint distributes uniformly, the highest is in base metal which is 110 HV and the lowest is in the welding joint which is 73 HV. The tensile strength of the welded joint is 281 MPa, the strength coefficient reached 70.6%. the fatigue strengths of the laser welded joint and the base metal are investigated. The results show that the conditional fatigue strength (10⁷) of the laser welded joint can reach up to 63.6% of that of the base metal. there are fatigue striations generated during the steady-state region.

• Periodical: Key Engineering Materials (Volume 734)
• Pages: 310-318
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.734.310
• Online since: April 2017
• Authors: Yi Shuai Jiang, Shang Lei Yang*, Yan Wang, Zhi Hua Yang
• Keywords: Aluminum Alloy, Laser Welding, Mechanical Properties, Microstructure

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