Features of laser impact treatment application with low-energy sources to reduce residual tensile stresses in the welds of aluminium alloys*

ABSTRACT

The strength of the welding joints which made of aluminium alloys is often significantly reduced, this is due to post-welding residual stresses and structural transformation. Laser shock peening (LSP) is effectively used as postprocessing, which allows to process extremely narrow sections of the transition zone of welds, increase of microhardness and depth of the residual compressive stress zone. However, despite the significant advantages of LSP over the other processing methods, it has some disadvantages. One of this disadvantages is the high cost of typical laser emitters for LSP. Therefore, it is advisable to switch from traditional laser sources to low energy sources. The effect of various process parameters on the result of LSP was investigated in this article.

KEYWORDS:

• Welding
• aluminium alloys
• laser shock peening
• residual stresses
• microhardness

Funding

The original work was undertaken with the support of the RNF (grant No. 17-19-01706).