Objective. Improve soiling and corrosion in stainless steel
The TEXENCO project “Laser surface texturing of stainless steels to improve behavior against soiling and corrosion phenomena” has as its main objective to design and transfer by laser a microstructure capable of avoiding the adhesion of ashes and soot inside the tubes of heat recoverers at the exhaust gas outlet of combustion vehicles. The second objective is to obtain greater resistance to corrosion of those microstructured tubes.
This project has received public funding under the AEI 2017 call from the Ministry of Industry, Commerce and Tourism, within the aid established to support innovative business groups with the aim of improving the competitiveness of small and medium-sized companies. The participating partners are Valeo Térmico, the Aragón Automotive Cluster CAAR and ATRIA.
Solution. Laser microstructure the surface
As a first step, we performed a literature search for laser texturing solutions for similar applications. Within this stage, we analyzed the size and distribution of ash and soot particles that are generated in the normal use of combustion engines.
After this stage, we designed and transfered different microstructures using lasers. These parts were tested on a test engine bench and streams of exhaust gas from the engines were passed through them so that ash and soot would accumulate.
To analyze the efficiency of the generated microstructures, various ad hoc tests were developed, with which the adhesion of the ash layers to the tubes and textured plates was analyzed.
Finally, we transferred with laser the microstructures with the best results to the total internal surface of the tubes and the ash accumulation test was carried out again to verify its result.
Additionally, to check the anticorrosive properties of the microstructures, we performed a test with a potentiostat to measure the corrosion potential. With the samples that gave the best results, we performed an accelerated life test with corrosive chemicals.