Steel Foam Pore Control via 3D Printed Inserts

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods are limited in producing steel foam components with consistent densities and predictable mechanical properties, restricting their industrial-scale production and application in high-strength, lightweight applications such as energy absorption and ballistic resistance.

Innovation Solution

A method involving a 3D-printed insert system within a mold, using sand bonded with a chemical binder, to create steel foam components with controlled pore structures, allowing for variable density and gradient density production, enabling consistent and predictable mechanical properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional casting methods are used to produce steel foam, then production cost is reduced, but density consistency and mechanical property predictability deteriorate

Engineering Contradiction:
Improvedensity consistencyVSAvoidproduction complexity
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The insert with predetermined pore structure is prepared before casting. The insert is positioned in the mold cavity beforehand, establishing the exact geometry and distribution of pores in advance. This preliminary preparation ensures that when molten steel is poured, the foam structure forms with consistent density and predictable mechanical properties, resolving the contradiction between manufacturing precision and production complexity.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The insert acts as an intermediary tool between the mold and the final steel foam product. It transfers the desired pore structure directly into the molten steel during casting. This intermediary device enables precise control over foam density and morphology without requiring complex post-processing or multiple casting stages, thus improving manufacturing precision while maintaining ease of production.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Strength

If steel foam is produced for high-strength applications, then mechanical properties improve, but production scalability deteriorates

Engineering Contradiction:
Improveballistic resistanceVSAvoidindustrial scale production
Core Design Contradiction:
StrengthVSProductivity

Solution Approach 1:

The steel foam production process is segmented into modular components: the insert with its pore structure, the mold cavity, and the molten steel pouring process. This segmentation allows each component to be optimized independently - the insert can be designed for high-strength applications while the modular assembly enables scalable industrial production. The segmented approach resolves the contradiction between achieving high mechanical properties and maintaining production scalability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The method controls foam density and mechanical properties by adjusting parameters such as insert material composition, pore size distribution, and molten steel temperature. These parameter changes enable the production of steel foam with high ballistic resistance while maintaining consistent quality across industrial-scale batches, thereby resolving the contradiction between strength and productivity.

Inventive Principle:
Principle #35Parameter changes

3Strength

If aluminum foam is used instead of steel foam, then production cost is reduced, but strength and hardness deteriorate

Engineering Contradiction:
ImprovestrengthVSAvoidproduction feasibility
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The invention changes the material parameter from aluminum to steel, leveraging steel's inherent higher strength and hardness properties. By using the same pore structure insert with steel instead of aluminum, the method achieves superior mechanical properties while maintaining production feasibility through a straightforward casting process. This parameter change resolves the contradiction between strength and ease of manufacture.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The steel foam produced through this method creates a composite structure combining steel matrix material with a controlled porous architecture. This composite approach enables the material to exhibit both the high strength characteristics of steel and the lightweight advantages of foam structures, resolving the contradiction between strength and manufacturing feasibility by optimizing the composite structure rather than relying on material substitution.

Inventive Principle:
Principle #40Composite materials

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

Enables the production of steel foam components with controllable densities and mechanical properties, suitable for industrial-scale manufacturing, offering enhanced strength, energy absorption, and ballistic resistance, with applications in military, naval, and civilian structures.

Implementation Method 1

Metal is considered a foam if pores are distributed within the metal to take up a certain minimum percentage of the total volume of the metal

Methodology Applied
Scientific EffectPorosity: Porosity

Implementation Method 2

A method involving a 3D-printed insert system within a mold

Methodology Applied
Scientific Effect3D Printing: 3D Printing

Data Source

PatentEP3233334B1Steel foam and method for manufacturing steel foam
Publication Date: 2020.10.07 MAYNARD STEEL CASTING CO
  • EP3233334B1 patent drawingFigure 1
  • EP3233334B1 patent drawingFigure 2
  • EP3233334B1 patent drawingFigure 3

AI summary

A method of producing a steel foam component includes providing a mold defining a cavity. The method also includes positioning an insert within the cavity of the mold. The insert can be configured to form a generally uniform pattern of pores within the steel foam component, and in some cases occupies at least 20% of the cavity. The method can further include pouring molten steel into the cavity, cooling the molten steel into the steel foam component, and removing the steel foam component and the insert from the mold. Steel components having internal shapes corresponding to the insert(s) are also provided.