Ring-Shaped Laser Deposition Head for Powder Usage Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The directed energy deposition method in additive manufacturing faces challenges with low material powder usage efficiency due to complex parameter combinations and difficulty in preventing powder scattering outside the melt pool, leading to inefficient processing and maintenance issues.

Innovation Solution

An additive-manufacturing head with a ring-shape laser beam forming unit using axicon lenses and a convex lens, along with moving mechanisms to control the laser-beam-irradiated region, allows for precise adjustment of the laser beam size and powder feeding to optimize the deposition process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of substance

If material powder is fed from outside the laser beam, then it is difficult to prevent scattering of the material powder to the outside of the melt pool, but feeding from inside the ring-shape laser beam improves powder usage efficiency

Engineering Contradiction:
Improvematerial powder usage efficiencyVSAvoidparameter combination complexity
Core Design Contradiction:
Loss of substanceVSDevice complexity

Solution Approach 1:

The laser beam is segmented into a ring shape with a hollow center, allowing the material powder feed to be spatially separated from the high-intensity heating zone while remaining within the overall beam structure. This segmentation enables the powder to be delivered through the central region without interfering with the annular heating pattern, thereby preventing powder scattering while maintaining efficient usage.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The material powder feed path is nested within the ring-shape laser beam structure. The powder delivery system is positioned through the hollow center of the annular beam, creating a nested configuration where the powder feed channel is contained within the outer boundary of the laser beam while occupying the central void space. This nesting allows simultaneous optimization of powder delivery and laser heating without mutual interference.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Manufacturing precision

If the size of the laser-beam-irradiated region is not controlled, then processing quality decreases, but controlling the region size requires additional moving mechanisms

Engineering Contradiction:
Improvelaser-beam-irradiated region controlVSAvoidmoving mechanism complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The optical system incorporates movable optical elements that can dynamically adjust the laser beam parameters in real-time. By moving the optical components along predetermined paths, the system dynamically changes the beam waist position and ring shape dimensions to match different processing requirements, enabling precise control of the irradiated region size without requiring complex mechanical positioning systems.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

Optical elements serve as intermediaries between the laser source and the workpiece, mediating the transformation of the laser beam characteristics. These intermediary optical components (such as lenses and mirrors) can be moved to adjust beam parameters, providing a sophisticated method of controlling the irradiated region size through optical manipulation rather than direct mechanical positioning of the entire system.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 enables efficient control of the laser-beam-irradiated region and material powder distribution, improving usage efficiency and stability in additive manufacturing, reducing waste and maintenance complexities.

Implementation Method 1

a ring-shape laser beam forming unit including a first axicon lens and a second axicon lens disposed to face each other in an optical axis direction of the laser beam, and a convex lens disposed between the first axicon lens and the second axicon lens, to form the laser beam entering through the first axicon lens into a ring-shape laser beam

Methodology Applied
Scientific EffectAxicon lens beam shaping: Lens

Implementation Method 2

an additive-manufacturing head performing additive manufacturing by feeding material powder to a workpiece and irradiating the workpiece with a laser beam

Methodology Applied
Scientific EffectLaser heating: Laser

Implementation Method 3

irradiating the workpiece with a laser beam

Methodology Applied
Scientific EffectLight absorption: Absorption (EM radiation)

Data Source

PatentEP3626383B1Additional-processing head and processing machinery
Publication Date: 2023.09.06 DMG MORI CO LTD
  • EP3626383B1 patent drawingFigure 1
  • EP3626383B1 patent drawingFigure 2
  • EP3626383B1 patent drawingFigure 3

AI summary

An additive-manufacturing head (21) includes: a ring-shape laser beam forming unit (32) having axicon lenses (43, 45) facing each other and a convex lens (44) between the axicon lenses (43, 45) to form a laser beam entering through the axicon lens (43) into a ring-shape laser beam and emit the ring-shape laser beam from the other axicon lens (45); a lens moving mechanism (81) to move the convex lens (44) in the optical axis direction of the laser beam; a laser beam emitting unit (34) to emit the ring-shape laser beam toward a workpiece; and a material powder feeding tube (61) having an outlet (62) which is disposed inside the ring-shape laser beam emitted from the laser beam emitting unit (34) and from which material powder is released, to feed the material powder from the outlet (62) toward the workpiece. Accordingly, the additive-manufacturing head capable of freely controlling the size of the laser-beam-irradiated region and the laser beam intensity distribution on the workpiece is provided.