- Laser treatment as SACO alternative
- Two-component polyurethane for bonding
- Delo and Ulm University of Applied Sciences (IFW) cooperate
Stainless steel is difficult to bond, and durable bonded connections are often only possible through pretreatment. Delo Industrial Adhesives and the Institute of Production Engineering and Materials Testing of the Ulm University of Applied Sciences have recently discovered that laser-pretreated stainless steel bondings are almost as durable as after SACO pretreatment.
Laser treatment as SACO alternative
Wet- or tribo-chemical methods, such as the SACO method (sandblasting and coating) are commonly used for stainless steel bondings. However, laser pretreatment (wavelength 1,024 nm) can be considered as a viable alternative due to several advantages over SACO: running costs in the process can be cut down, in-line processes are possible, and selective pretreatment is easier to implement.
In collaboration with DELO, the Ulm University of Applied Sciences investigated how dissimilar laser intensities influence the surface topology of stainless steel (1.4301). A two-component polyurethane was used for bonding. The effectiveness of surface pretreatment was verified by tensile shear tests.
Result: at the maximum processing intensity, the specimens pretreated by a laser achieve tensile shear strength values after simulated aging, which are similar to those of SACE-pretreated specimens.