Dual-Scanner Laser Steering for Precise Powder Bed Melting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing additive manufacturing technologies face challenges in achieving precise control over energy beam scanning in selective laser melting and sintering processes, leading to issues like warping, curling, and elongate melt pools due to limitations in dynamic response and absorption of high-power laser beams by traditional beam steering components.
Innovation Solution
A scanner system utilizing a combination of beam steering components with different dynamic responses, where a faster dynamic response component compensates for the slower response of another, allowing for precise control and reduced absorption, enabling sharper changes in direction and reduced build time by 'hopping' the energy beam across the powder bed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a single beam steering component is used to direct the laser beam, then the device complexity is reduced, but the dynamic response is insufficient leading to elongate melt pools and reduced manufacturing precision
Solution Approach 1:
The patent combines two beam steering components (first and second scanners) with different dynamic response characteristics into a single integrated scanner system. The first scanner provides coarse positioning while the second scanner provides fine adjustments, merging their functions to achieve both high precision and fast response without requiring entirely separate systems.
Solution Approach 2:
The beam steering function is segmented into two distinct components with different capabilities. The first scanner handles the primary scanning motion while the second scanner handles rapid directional changes and fine positioning. This segmentation allows each component to be optimized for its specific function, resolving the contradiction between simplicity and performance.
2Productivity
If continuous mode laser operation is used, then the productivity is improved, but the melt pool becomes elongate and manufacturing precision deteriorates
Solution Approach 1:
The system uses periodic pulsed laser operation instead of continuous mode. The laser is activated in controlled pulses that allow the melt pool to solidify between pulses, preventing excessive elongation while maintaining high productivity through rapid sequential pulsing. This periodic action resolves the contradiction between continuous operation speed and precision.
3Device complexity
If traditional beam steering components are used, then the device complexity is reduced, but thermal loads increase causing warping and curling
Solution Approach 1:
The system uses dynamic beam steering with two scanners that can rapidly adjust the laser path. This dynamic capability allows the laser to hop between locations and pause at key points, reducing continuous thermal loading on any single area and preventing warping and curling while maintaining a relatively simple overall device structure.
4Productivity
If the laser beam is scanned continuously across the powder, then the productivity is improved, but the thermal loads become excessive causing warping
Solution Approach 1:
The laser operation is converted from continuous scanning to periodic pulsed scanning. The laser delivers energy in controlled pulses with intervals between them, allowing heat to dissipate and preventing excessive thermal accumulation that causes warping, while maintaining high productivity through rapid sequential pulsing across the powder bed.
Solution Approach 2:
The beam steering system enables the laser to skip across the powder bed by hopping between discrete locations rather than continuously scanning across all intermediate areas. This skipping approach reduces total exposure time and thermal loads on any given region, preventing warping while maintaining fast build speeds.
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
This solution allows for more accurate and detailed solidification lines, reducing thermal loads and build time, while maintaining high power laser operation without overheating, thus improving the quality and efficiency of additive manufacturing processes.
Implementation Method 1
a first beam steering component for deflecting the energy beam over a first range of angles in a first dimension
Implementation Method 2
a second beam steering component for deflecting the energy beam over a second range of angles in the first dimension
Implementation Method 3
A laser beam is then scanned across areas of the powder layer that correspond to a cross-section of the object being constructed. The laser beam melts or sinters the powder to form a solidified layer.
Implementation Method 4
The laser beam melts or sinters the powder to form a solidified layer
Implementation Method 5
The laser beam melts or sinters the powder to form a solidified layer
Data Source
AI summary
An additive manufacturing apparatus including a scanner for directing a laser beam on to layers of flowable material to selectively solidify the material to form an object in a layer-by-layer manner. The scanner includes an optical component operable under the control of a first actuator to reflect the laser beam over a first range of angles in a first dimension and the or a further optical component operable under the control of a second actuator to reflect the laser beam over a second range of angles in the first dimension, wherein the second actuator provides a faster dynamic response but a smaller range of movement of the laser beam than the first actuator.