Selective Laser Sintering Composite Particles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current selective laser sintering (SLS) methods face challenges in incorporating high loadings of conductive materials like carbon nanotubes into polymer powders, leading to inadequate conductivity and material degradation at high sintering temperatures, which limits the creation of functional 3D objects with embedded sensors and electronics.
Innovation Solution
The method involves using composite particles made by emulsion aggregation, incorporating at least 5% by weight of carbon nanotubes, graphene, or graphite with thermoplastic polymers, allowing for improved dispersion and increased electrical conductivity while maintaining suitable melt temperatures for SLS processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high loadings of conductive materials (e.g., graphitic materials) are incorporated into polymer composites to enable high conductivity, then electrical conductivity is improved, but melt temperature increases to over 250°C or 300°C which may render materials unsuitable for printing and cause polymer degradation
Solution Approach 1:
The patent changes the particle size parameter of conductive materials to sub-100 nm range and controls their distribution within the polymer matrix. This parameter change allows achieving high electrical conductivity (greater than 1 S/cm) while maintaining melt temperatures suitable for SLS printing (below 250°C), thereby resolving the contradiction between conductivity and temperature
Solution Approach 2:
The patent creates a composite material system combining polymer matrix with specifically engineered conductive particle fillers. The composite structure allows the polymer to maintain its processability while the conductive particles provide electrical functionality, achieving both high conductivity and suitable processing temperatures through proper material composition design
2Reliability
If conventional mixing methods are used to incorporate conductive materials into polymer powders, then processing is simple, but dispersion is inadequate and conductivity is insufficient
Solution Approach 1:
The patent performs preliminary dispersion of conductive materials in a liquid carrier before incorporating into polymer powder. This preliminary action ensures uniform distribution of conductive particles throughout the polymer matrix, achieving high conductivity without requiring complex mixing processes during SLS printing
Solution Approach 2:
The patent uses a liquid carrier as an intermediary medium to disperse conductive materials uniformly before incorporating them into the polymer powder. This intermediary approach simplifies the overall manufacturing process while achieving superior dispersion and conductivity compared to direct mixing methods
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 enables the production of 3D objects with enhanced electrical conductivity and improved processability, using a broader range of polymers and particle sizes, while retaining material properties suitable for additive manufacturing, such as FDM filaments and pastes.
Implementation Method 1
a rasterized laser is used to 'scan' over a bed of polymer powder, sintering it to form solid shapes
Implementation Method 2
The composite particles are exposed to a laser to fuse the composite particles
Data Source
Figure 1
Figure 2
Figure 3A~3C
AI summary
A method of selective laser sintering is disclosed. The method comprises providing composite particles made by emulsion aggregation, the composite particles comprising at least one thermoplastic polymer and at least one carbon particle material. The composite particles are exposed to a laser to fuse the composite particles.