Additive Manufacturing Binder Shell for Metal Part Strength
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Additive manufacturing methods using granular materials, such as metal powders, face challenges in achieving improved mechanical properties due to the interference of binder coatings during the sintering process, which reduces hardness and strength compared to sintered parts without binders.
Innovation Solution
The method involves depositing a granular metal construction material with a binder forming a contiguous shell around an unbound region, followed by debinding and sintering, where the shell and enclosed material sinters together at a temperature below the melting point, allowing for improved mechanical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If binder is deposited to bind granular construction material particles together, then the object can be formed and handled, but the mechanical properties (hardness and strength) are reduced due to binder interference during sintering
Solution Approach 1:
The patent extracts the binder from the bulk material regions and retains it only in the shell region. This selective removal of binder from interior regions allows the granular particles in those regions to sinter directly without binder interference, achieving high mechanical properties while maintaining manufacturability through the shell binder
Solution Approach 2:
The patent applies different binder distributions to different regions of the object: the shell region contains binder for structural integrity and handling, while the bulk interior regions are free of binder to enable high-strength sintering. This local differentiation resolves the contradiction between manufacturability and mechanical properties
2Productivity
If binder is used to adhere granules together, then the object can be built layer by layer, but the sintering process is interfered with and mechanical properties are reduced
Solution Approach 1:
The patent segments the object into shell regions and bulk regions with different binder characteristics. The shell provides the necessary binding for layer-by-layer construction, while the bulk regions remain binder-free for optimal sintering. This segmentation allows both productivity and strength requirements to be met simultaneously
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 results in objects with enhanced mechanical properties, such as increased hardness and compressive strength, by minimizing the presence of binder within the sintered structure, thereby overcoming the limitations of binder-interfered sintering.
Implementation Method 1
portions of each layer being bound together during or after deposition of each layer to form portions of an object, thereby forming the object in the build region from the series of layers. The binding is typically carried out by selective deposition of a binder.
Implementation Method 2
objects made from metal powders as the granular construction material can be sintered, for example by heating to a temperature below the melting point of the metal, to achieve an object with substantially improved mechanical properties
Data Source
AI summary
The present disclosure provides an additive manufacturing method for manufacturing an object. The method comprises depositing successive layers of a granular metal construction material. The method comprises selectively binding a first region of each layer to form a bound shell of the construction material defining an exterior of the object by depositing a binder into the first region surrounding a second region that remains unbound. The method comprises separating the shell and the enclosed unbound construction material from the construction material remaining outside the shell. The present disclosure also provides apparatuses implementing the manufacturing method, and objects manufactured by the manufacturing method.