Material Evaluation and Process Optimization of CNT-Coated Polymer Powders for Selective Laser Sintering

Area of Science:

• Materials Science
• Polymer Engineering
• Nanotechnology

Background:

• Laser sintering of polymers requires precise control of material properties.
• Enhancing thermal and mechanical performance of polymer composites is crucial for advanced applications.
• Carbon nanotubes (CNTs) offer unique properties for material reinforcement.

Purpose of the Study:

• To investigate the use of CNTs in polyamide 12 (PA12) for improved laser sintering.
• To evaluate the processability and predict optimal process parameters for CNTs/PA12 powders.
• To characterize the thermal and mechanical enhancements in CNTs/PA12 composites.

Main Methods:

• Characterization of thermal conductivity, melt viscosity, phase transition, density, and heat capacity for PA12 and CNTs/PA12 powders.
• Development of a dual experimental-theoretical method for processability evaluation.
• Microstructural analysis of sintered composites to observe CNT distribution and network formation.

Main Results:

• CNTs/PA12 powders showed enhanced heat conduction and absorption compared to virgin PA12.
• The stable sintering range for CNTs/PA12 was extended, facilitating the laser sintering process.
• Microstructural analysis revealed CNTs forming networks at powder boundaries, leading to significant improvements.

Conclusions:

• CNTs effectively facilitate laser sintering and enhance the properties of PA12.
• The developed method accurately predicts process parameters for CNTs/PA12.
• Significant improvements in tensile strength, elongation at break, and toughness were achieved without compromising tensile modulus.