Researchers from Seoul National University of Science and Technology in Korea have explored how laser surface texturing (LST) patterns impact the strength and durability of joints in lightweight vehicle design.
By applying LST to automotive steel and joining it with plastic materials, they found that LST processing significantly improved joint strength and resistance to tensile stress and vibration fatigue. This technique helps reduce vehicle weight, boost fuel efficiency, and lower greenhouse gas emissions.
This research led by Professor Changkyoo Park, discovered how specific patterns can significantly improve the performance of metal-polymer joints under conditions mimicking real-world stresses, vital for reducing vehicle weight and improving fuel efficiency.
“This method provides a breakthrough for joining metal and plastic, two materials traditionally challenging to bond due to differences in their physical properties,” explained Park.
“By grooving different LST patterns on the surface of AHSS and joining it with glass fiber-reinforced polyamide 6 (PA 6) using injection moulding, we significantly improved the mechanical interlock and overall strength of the joints.”
The study focused on specific LST patterns, including diagonal and orthogonal designs, which significantly improved resistance to wear and tear and tensile shear strength, achieving up to 78.9 MPa—much higher than traditional automotive structural adhesives that typically achieve around 25 MPa.
Practically, this technique could address a key challenge in the automotive industry: reducing vehicle weight to meet fuel efficiency and emission standards.
This advancement has significant real-world applications, including enhancing safety and performance in road driving conditions. “Laser surface texturing is fast and programmable, allowing optimal strength and longevity at any desired joints in the car body and chassis,” Park said.
The original paper was published in the Optics & Laser Technology journal under the title: Effect of laser surface texturing pattern on mechanical properties in metal-polymer direct joining.