Bi-Metal Build Platform With Graded Porosity for Metal AM Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing additive manufacturing build platforms face issues with print material adhesion and thermal expansion compatibility, leading to build failures, especially at high temperatures, due to material incompatibilities, which result in high costs when using compatible materials and low costs when using incompatible materials.
Innovation Solution
A bi-metallic build platform with a graded porosity surface layer, where the base is made of a first metal and the surface layer is made of a second metal compatible with the print material, featuring a graded porosity structure to enhance adhesion and thermal expansion compatibility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If build platforms are made entirely from material compatible with the print material (e.g., stainless steel or nickel-based alloys), then adhesion and thermal expansion compatibility are improved, but manufacturing cost increases significantly
Solution Approach 1:
The build platform is divided into two distinct segments: a base portion made from inexpensive material (first metal) and a surface layer made from compatible material (second metal). This segmentation allows each portion to be optimized independently - the base for cost-effectiveness and the surface layer for adhesion and thermal compatibility with the print material.
Solution Approach 2:
Different portions of the build platform are assigned different material properties according to their functional requirements. The surface layer uses compatible material (second metal) to ensure good adhesion and thermal expansion matching with the print material, while the base portion uses inexpensive material (first metal) to reduce overall cost. This local differentiation of material quality resolves the contradiction between reliability and manufacturing cost.
2Ease of manufacture
If lower cost materials (e.g., certain types of steel) are used for the build platform, then manufacturing cost decreases, but adhesion and thermal expansion compatibility with advanced print materials (e.g., nickel-based alloys, superalloys) deteriorates
Solution Approach 1:
The build platform is segmented into a base portion that can be made from low-cost material and a surface layer that provides the necessary compatibility. This allows the system to benefit from both inexpensive base material and compatible surface material, resolving the contradiction between cost and reliability.
Solution Approach 2:
The build platform uses a composite structure combining two different metals: a base portion made from inexpensive metal (first metal) and a surface layer made from compatible metal (second metal). This composite approach allows the platform to exhibit both cost-effectiveness and the necessary adhesion/thermal properties for advanced print materials.
3Strength
If the surface layer has high porosity to enhance adhesion, then bonding strength improves, but thermal expansion compatibility and structural integrity deteriorate
Solution Approach 1:
The surface layer exhibits graded porosity where different regions have different porosity levels. The upper portion of the surface layer has lower porosity to maintain thermal expansion compatibility and structural integrity, while the lower portion (contacting the base) has higher porosity to enhance adhesion. This local variation in porosity resolves the contradiction between adhesion strength and thermal/structural reliability.
Solution Approach 2:
The porosity parameter is changed gradually across the thickness of the surface layer, creating a gradient from higher porosity at the base interface to lower porosity at the upper surface. This parameter change allows the surface layer to simultaneously achieve good adhesion (via higher porosity regions) and maintain thermal expansion compatibility (via lower porosity regions), resolving the contradiction between these two requirements.
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 bi-metallic build platform ensures strong adhesion and thermal expansion compatibility, reducing build failures and costs by using a less expensive material combination while maintaining performance in high-temperature environments.
Implementation Method 1
the ability of the print material to wet and bond (weld) to the build platform is advantageous
Implementation Method 2
graded porosity structure to enhance adhesion
Implementation Method 3
Coefficient of thermal expansion (CTE) compatibility of the build platform to the print material is another characteristic to be considered. Significant differences in CTE can result in separation of the bond between the print material and the build platform
Implementation Method 4
Certain additive manufacturing methods use lasers or electron beams to sequentially sinter metal layers to form a 3D part
Implementation Method 5
where electron beams are used, the process may be referenced as, for example, electron beam melting (EBM)
Implementation Method 6
Certain additive manufacturing methods use lasers or electron beams to sequentially sinter metal layers to form a 3D part
Data Source
AI summary
A build platform for a metal additive manufacturing process and a related method are disclosed. The build platform includes a base including a first metal and an upper surface. The build platform also includes a surface layer on the upper surface of the base including a second metal different than the first metal. The surface layer has a graded porosity having a most-dense region at an upper surface of the surface layer and a least-dense region at a lower surface of the surface layer. The lower surface of the surface layer contacts the upper surface of the base.