Halogen-Free Powder for Additive Manufacturing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current powder bed fusion technologies face challenges in achieving improved recyclability, mechanical properties, post-processing properties, and printability while maintaining standardized flame-retardant ratings, and they often rely on halogen-based flame-retardant materials.
Innovation Solution
A powder composition for use in powder bed fusion methods, comprising 60-99% by weight of a thermoplastic polymer with a melting temperature below 175°C, 1-40% by weight of a halogen-free inorganic flame retardant, and 0-25% by weight of additives, which enables the production of flame-protected articles with enhanced properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If halogen-based flame-retardant materials are used in powder bed fusion, then flame retardancy is improved, but environmental safety and material recyclability deteriorate
Solution Approach 1:
The patent changes the chemical composition parameters of the flame retardant system by replacing halogen-based compounds with phosphorus-containing compounds (e.g., ammonium polyphosphate, red phosphorus, zinc phosphide) and metal hydroxides (e.g., aluminum hydroxide, magnesium hydroxide). This parameter change maintains flame retardancy while eliminating harmful halogen emissions, thus resolving the contradiction between flame safety and environmental safety.
Solution Approach 2:
The patent employs composite flame retardant systems combining multiple components such as phosphorus-containing compounds with metal hydroxides, or organic phosphates with inorganic fillers. These composite materials provide synergistic flame retardant effects while avoiding halogenated compounds, thereby achieving both effective flame protection and environmental safety.
2Reliability
If flame retardant additives are added to polymer powder, then flame retardancy is improved, but mechanical properties and printability deteriorate
Solution Approach 1:
The patent optimizes the concentration parameters of flame retardant additives, typically maintaining them within 5-30 wt% of the total polymer composition. This controlled parameter range ensures sufficient flame retardancy while minimizing the negative impact on mechanical properties and printability.
Solution Approach 2:
The patent uses composite formulations where flame retardant additives are combined with reinforcing fillers (such as glass fibers, carbon fibers, or mineral fillers) to compensate for potential mechanical property reductions. The synergistic effect of the composite material maintains or even enhances mechanical strength while providing flame retardancy.
3Reliability
If flame retardant materials are used in powder bed fusion, then flame retardancy is improved, but recyclability of powder deteriorates
Solution Approach 1:
The patent selects flame retardant compounds with thermal stability parameters that match the polymer processing temperature range. By choosing additives that remain stable and do not decompose or volatilize during the sintering process (typically below 200°C), the powder maintains its properties through multiple recycling cycles without degradation.
Solution Approach 2:
The patent employs flame retardant systems that do not require additional post-processing treatments or special handling procedures. The additives are inherently stable and compatible with the polymer matrix, allowing the powder to be directly reused after simple sieving and removal of unsintered particles, thus maintaining high recyclability.
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 proposed powder composition achieves improved recyclability, mechanical properties, post-processing properties, and printability, while maintaining excellent flame retardancy and avoiding the use of halogen-based flame-retardant materials.
Implementation Method 1
the work piece is successively built up layer by layer by selective irradiation from above with a laser, which irradiates only the areas to be solidified and causes this solidification by melting the material
Implementation Method 2
causes this solidification by melting the material
Implementation Method 3
Powder bed fusion (PBF) technologies is an additive manufacturing process to produce spatial structures by sintering with a laser
Implementation Method 4
the melt solidifies when it falls below the solidification temperature of the polymer
Implementation Method 5
the block is slowly cooled, and the melt solidifies when it falls below the solidification temperature of the polymer
Implementation Method 6
1-40% by weight of a halogen-free inorganic flame retardant
Data Source
AI summary
Powder for the production of mouldings in a layer-by-layer process in which areas of a powdered layer are selectively melted, sintered, fused, or solidified,wherein the powder consists of the following components:a) 60-99% by weight of a thermoplastic polyamide with a melting temperature smaller than 175° C.;b) 1-40% by weight of a mineral inorganic flame retardant;c) 0-25% by weight of additives;wherein the components a)-c) add up to 100% by weight of the total material of the powder.