Southwest Manufacturing News • Nov 19 • Optimize Coated Cylinder Bores with Laser Roughening

The appropriate adhesion for cylinder bore coating is a perquisite to increase engine efficiency. For this purpose, high-resolution micro-structures are created with a laser beam onto the substrate surface, allowing formation for a variety of adhesive properties.

Technology capable of thermally coating cylinder bores is a highly soughtafter solution. High performance roughening is required to produce a reliable bond between the layer and substrate, ensuring all aspects of functionality. A positive interlocking connection is achieved by undercutting and the complete filling of the profile’s roughness; microscopically and evenly sprayed materials are crucial requirements for layer adhesion.

The purpose of laser roughening is a micro-positive interlocking connection across the entire surface, enabling a high level of adhesive strength, resulting in an appropriate and robust layer in all directions.

Blast parameters and process kinematics allow roughening topographies for both spiral profiled grooves or enclosed cavities. When energy enriched beams of light identify the material, the energy is absorbed locally and converted into heat. When the appropriate parameters are selected, formation of the profile roughness is ideally matched to the function, for both aluminum and cast iron materials.

“Operating costs are relatively low due to the lack of mechanical machining typically associated with high tooling costs. Additionally, laser roughening delivers substantial material cost savings due to the high levels of adhesive strength achieved with low roughness,” said a company spokesperson.

The compact design of laser spindles allows for two identical cylinder bores to be machined simultaneously. The hollow-shaft motor and stationary submersed optical system enables operation, virtually without vibration.

An industrial based sensor is used to monitor the process, particularly during the set-up stage. The optical equipment for the fully automated roughening module, with an optimized footprint, includes an extraction system and coolant device for the laser beam and spindle sources.

“Our years of expertise in enginebased technologies, including a wide variety of performance categories, demonstrates laser roughening’s innovative and cost-effectiveness for today’s manufacturing processes. Laser roughening is applicable for pre-treating all conventional thermal coating processes,” said the spokesperson.

“Gehring has extensive expertise across all areas of the laser roughening, coating and honing process chains. Our synchronized process steps result in reduced friction and wear-resistant cylinder surfaces,” said the spokesperson.