Blue Laser Metal Additive Manufacturing with DMD
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Infrared (IR) based additive manufacturing systems face limitations in build volume and speed due to finite scanning system sizes and high reflectivity of metals, leading to inefficient energy coupling and resolution issues, with existing solutions failing to overcome keyhole welding defects and spatter problems.
Innovation Solution
The use of a laser source with a digital micro-mirror device (DMD) and spatial light modulators to create high-power density patterns on metal powders, employing blue or green wavelengths for improved absorptivity and energy efficiency, allowing for simultaneous heating and fusion without keyhole welding, and utilizing a secondary laser for pre-heating to enhance build speed and resolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of stationary object
If infrared laser systems are used for additive manufacturing, then the process can be implemented with existing technology, but the build volume is limited by the finite size of scanning systems and spot size
Solution Approach 1:
The patent changes the fundamental parameter of laser wavelength from infrared to blue/green visible spectrum. This parameter change enables much smaller spot sizes (diffraction-limited) while maintaining or increasing build volume, as the smaller wavelength allows for tighter focusing without being constrained by the longer wavelength limitations of IR systems.
Solution Approach 2:
The patent introduces a new dimension to the problem by moving from infrared to visible spectrum laser wavelengths. This dimensional change in the electromagnetic spectrum allows simultaneous achievement of small spot sizes and large build volumes, breaking the traditional trade-off that exists in IR-based systems.
2Productivity
If infrared laser systems are used for additive manufacturing, then the system can process materials, but the build speed is limited by high reflectivity of metals causing inefficient energy coupling
Solution Approach 1:
The patent changes the laser wavelength parameter from infrared to blue/green visible spectrum (400-500 nm). Metals have much lower reflectivity and higher absorptivity at these wavelengths compared to infrared, enabling significantly improved energy coupling efficiency and build speed without the energy loss problems inherent in IR systems.
3Manufacturing precision
If infrared laser systems are used for additive manufacturing, then the process can be implemented, but the resolution is limited by finite penetration depth of infrared laser light
Solution Approach 1:
The patent changes the laser wavelength from infrared to blue/green visible spectrum. The shorter wavelength enables diffraction-limited spot sizes and deeper penetration into metal powders, dramatically improving resolution and eliminating the penetration depth limitations that constrain IR-based systems.
4Reliability
If keyhole welding mode is used in infrared laser additive manufacturing, then metal powder can be fused, but spatter and defects occur
Solution Approach 1:
The patent changes the laser wavelength from infrared to blue/green visible spectrum, which fundamentally alters the interaction with metal materials. This parameter change enables fusion at lower power densities without reaching the keyhole welding regime, thereby eliminating spatter and defects while maintaining reliable part quality.
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 approach significantly increases build speed and resolution, reduces spatter and defects, and enables the production of larger parts with improved surface quality and reproducibility by optimizing energy coupling and absorption, overcoming the limitations of IR systems.
Implementation Method 1
metals, such as gold, silver, platinum, copper and aluminum and alloys thereof, which materials have high and very high IR reflectivity... the coupling of the infrared laser energy into the raw build materials, e.g., powder bed or particles, is limited with a significant portion of the energy being reflected away
Implementation Method 2
laser building of materials including laser additive manufacturing processes using laser beams
Implementation Method 3
existing solutions failing to overcome keyhole welding defects and spatter problems
Data Source
AI summary
A high-resolution additive manufacturing system based on a parallel printing method using a spatial light modulator. A method and system for additive manufacturing using a DMD in the laser beam path. The use of a pre-heat laser beam in combination with a build laser beam having a DMD along the build laser beam path.