Additive Manufacturing Feedstock with Negative Thermal Expansion MOF
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional materials used in additive manufacturing exhibit positive thermal expansion, leading to potential warping, stress, and material failure when exposed to temperature changes, especially in confined environments, and adhesion issues at material interfaces due to thermal expansion mismatches.
Innovation Solution
Combining a first material with a metal organic framework (MOF) having a negative coefficient of thermal expansion to create a feedstock material with reduced thermal expansion properties, achieved by selecting and tailoring the MOF's composition and structure to offset the positive thermal expansion of the first material, thereby minimizing dimensional changes under temperature variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional materials with positive thermal expansion are used in additive manufacturing, then the materials are easy to process and maintain structural integrity at room temperature, but the materials expand and warp when exposed to temperature changes, causing dimensional inaccuracies and stress
Solution Approach 1:
The patent changes the thermal expansion parameter of the feedstock material by incorporating MOF particles with negative thermal expansion coefficients. This modifies the effective coefficient of thermal expansion of the composite material from positive to near-zero, preventing warping and dimensional changes during temperature variations in the additive manufacturing process.
Solution Approach 2:
The patent creates a composite material system combining conventional PTE material with NTE MOF particles. The composite structure allows the beneficial negative thermal expansion properties of the MOF to offset the positive thermal expansion of the base material, achieving near-zero thermal expansion while maintaining the processability of conventional materials.
2Manufacturing precision
If materials with low thermal expansion are used to prevent warping, then dimensional stability is improved, but the materials may exhibit poor adhesion at interfaces due to thermal expansion mismatches with other materials
Solution Approach 1:
The patent carefully controls the thermal expansion parameter of the composite material by adjusting the concentration and type of MOF particles. This allows tuning the effective coefficient of thermal expansion to achieve near-zero expansion for dimensional stability while maintaining compatibility with other materials for reliable adhesion at interfaces.
3Object-affected harmful factors
If MOF particles are added to reduce thermal expansion, then the thermal expansion properties are improved, but the complexity of material preparation and characterization increases
Solution Approach 1:
The patent establishes specific parameter ranges for MOF particle characteristics (size, concentration, surface area) and feedstock material composition to achieve the desired thermal expansion properties. By defining these parameters, the complex process of material preparation can be standardized and controlled.
Solution Approach 2:
The patent employs computational methods and predictive models to characterize the thermal expansion properties of the composite material and guide the selection of MOF particles. This reduces the need for extensive experimental trial-and-error in material development.
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 resulting composite material exhibits lower thermal expansion characteristics, reducing the risk of warping, stress, and adhesion issues, while maintaining the design flexibility and efficiency of additive manufacturing processes.
Implementation Method 1
a metal organic framework (MOF) having a coefficient of thermal expansion less than the coefficient of thermal expansion for the first material. For instance, the MOF may have a negative coefficient of thermal expansion
Data Source
AI summary
A feedstock material for use in an additive manufacturing apparatus is prepared from a first material and a metal organic framework (MOF). The MOF comprises a plurality of nodes and a plurality of linkers, the plurality of linkers coupled to the plurality of nodes, thereby forming a framework. The MOF has a lower coefficient of thermal expansion than a coefficient of thermal expansion for the first material. As a result, the feedstock material has a reduced coefficient of thermal expansion as compared to the first material alone and thus exhibits low thermal expansion as its temperature is increased. The coefficient of thermal expansion for the MOF may be modified by using a different plurality of nodes and/or a different plurality of linkers, as well as by incorporating guest molecules or atoms into the framework of the MOF.