Laser Cladding of Metallic Coatings Using Surface Microstructure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing metallic coating processes using laser deposition welding for brake discs face issues with laser beam reflection, causing the metal powder to melt in the nozzles and requiring frequent maintenance due to full reflection of the laser beam back to the coating head, especially when the angle is unfavorable.
Innovation Solution
A microstructure is applied to the processing surface to scatter the laser beam upon reflection, minimizing the amount of laser beam reflected back to the coating head, thereby preventing nozzle clogging and reducing maintenance needs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a smooth machining surface is used for laser deposition welding, then the coating process can be performed, but the laser beam reflects fully back to the coating head causing nozzle clogging and frequent maintenance
Solution Approach 1:
A microstructure is applied to the machining surface before the laser deposition welding process. This preliminary surface treatment creates irregularities that scatter the laser beam upon reflection, preventing full reflection back to the coating head and eliminating nozzle clogging before the coating process begins
Solution Approach 2:
The invention converts the harmful full reflection of the laser beam into beneficial scattered reflection. By introducing a microstructure to the surface, the previously harmful concentrated reflection is transformed into dispersed reflection patterns that redirect laser energy away from the coating head nozzles
2Ease of operation
If the coating process is interrupted for maintenance, then nozzle clogging is cleared, but productivity decreases due to frequent maintenance intervals
Solution Approach 1:
The microstructure is applied in advance to the machining surface to prevent nozzle clogging before it occurs. This preliminary protective measure eliminates the need for frequent maintenance interruptions, allowing the coating process to continue uninterrupted and maintaining high productivity
3Reliability
If the laser beam hits the nozzles at an unfavorable angle, then metal powder melts in the nozzles causing clogging, but changing the angle may affect coating quality
Solution Approach 1:
Instead of trying to avoid unfavorable angles or protect the nozzles directly, the invention uses the microstructure to convert the harmful concentrated reflection at any angle into beneficial scattered reflection. This allows the coating process to maintain flexibility with various angles while preventing nozzle clogging
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The microstructured surface effectively reduces and prevents full reflection of the laser beam, minimizing nozzle clogging and extending maintenance intervals, allowing for a more efficient and cost-effective coating process.
Implementation Method 1
A microstructure is applied to the processing surface to scatter the laser beam upon reflection, minimizing the amount of laser beam reflected back to the coating head
Implementation Method 2
The laser melts the metal powder, which is sprayed onto the working surface, and thus bonds it to the working surface
Data Source
Figure 1
Figure 2
AI summary
The invention relates to a method for metallically coating a flat machining surface of a workpiece by laser cladding using a coating head which has an exit aperture for a laser beam and at least one exit nozzle offset therefrom for a metal powder. Metal powder is sprayed onto the machining surface to be coated through the at least one exit nozzle and is thereby melted by the laser beam to form a coating. The coating head is moved across the machining surface during this process. According to the invention, the machining surface is provided with a microstructure before coating. The invention further relates to a system for carrying out the method according to the invention.