Laser Cutting of High-Strength Steel for Accurate Blank Trimming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High strength steel cutting processes face challenges with residual stress relief, leading to poor geometric accuracy and increased process scrap, particularly when cutting long and narrow blanks, which are critical for applications like tailor welded blanks in automotive manufacturing.
Innovation Solution
A laser cutting process involving multiple steps, including positioning, clamping, cutting, separating, and trimming of sub-blanks using a cutting table with moveable laths and magnetic clamping, to produce high-quality, geometrically accurate trimmed sub-blanks with low scrap, suitable for high-strength steels above 980 MPa ultimate tensile strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional laser cutting is used on high strength steel, then cutting speed is maintained, but geometric accuracy deteriorates due to residual stress relief
Solution Approach 1:
The cutting process is divided into two distinct stages: a first cutting operation that separates sub-blanks from the mother blank, followed by a second trimming operation that achieves final geometric precision. This segmentation allows the first cut to proceed quickly without worrying about final accuracy, while the second cut focuses solely on precision without compromising overall productivity.
Solution Approach 2:
The first cutting operation performs a preliminary separation of sub-blanks before the final trimming. By pre-positioning the sub-blanks and removing them from the mother blank in advance, the process enables the subsequent trimming operation to focus exclusively on achieving geometric accuracy without the constraints of maintaining cutting speed.
2Productivity
If conventional laser cutting is used on high strength steel, then productivity is maintained, but process scrap increases due to poor edge quality
Solution Approach 1:
The two-stage cutting process separates the functions of material separation and edge quality optimization. The first cut efficiently divides the mother blank into sub-blanks, while the second trimming cut specifically addresses edge quality issues, thereby reducing scrap generation without compromising overall production output.
Solution Approach 2:
The process changes cutting parameters between the two operations. The first cutting operation uses parameters optimized for speed and efficiency, while the second trimming operation uses parameters optimized for edge quality and geometric precision, thereby minimizing scrap while maintaining productivity.
3Shape
If high strength steel is cut into long and narrow blanks, then application requirements are met, but geometric accuracy deteriorates due to residual stress relief
Solution Approach 1:
The process segments the cutting operations so that the first cut creates the long and narrow blank shape, while the second trimming operation specifically addresses the geometric accuracy issues that arise from residual stress relief in these particular geometries.
Solution Approach 2:
The trimming operation applies localized quality improvement to specific areas of the blank that are most affected by residual stress relief, particularly along the long edges and narrow sections where geometric accuracy is most critical for applications like floor panels and rocker reinforcements.
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 process achieves excellent blank geometry, edge quality, and productivity while minimizing process scrap, ensuring precise cutting of high-strength steel blanks for applications like floor panels and rocker reinforcements in automotive manufacturing.
Implementation Method 1
Op3/ cutting, using a laser source, n untrimmed sub-blanks from the mother blank in a longitudinal cutting direction
Implementation Method 2
Op7/ laser trimming the n untrimmed sub-blanks in order to form n trimmed sub-blanks
Implementation Method 3
The clamping operations Op2 and Op6 are performed using magnetic clamping
Data Source
AI summary
Laser cutting process to produce n trimmed sub-blanks, n being an integer strictly greater than 1, from a mother blank made of metallic material, having the following steps: Op1/ positioning the mother blank on a cutting table having n laths arranged to be moveable relative to one another in a transverse direction, Op2/ clamping at least part of the mother blank to the cutting table, Op3/ cutting, using a laser source, n untrimmed sub-blanks from the mother blank in a longitudinal cutting direction, Op4/ separating the n laths of the cutting table from one another in a transverse direction, Op5/ releasing the clamping, Op6/ clamping the n untrimmed sub-blanks to the n laths, Op7/ laser trimming the n untrimmed sub-blanks in order to form n trimmed sub-blanks, Op8/ releasing the clamping, Op9/ discharging the n trimmed sub-blanks from the cutting table.