Recently, Canadian startup Fortis3D is launching two new 3D printing polymer materials for industrial applications, which are PA-GF20 and PK-GF20, Mohou.com learned.

Recently, Canadian startup Fortis3D is launching two new 3D printing polymer materials for industrial applications, which are PA-GF20 and PK-GF20, Mohou.com learned.

Along with the launch of the new materials, Fortis3D has also provided a detailed analysis of the material properties of each filament to facilitate engineers in finding the right application scenario based on the material advantages. Based on a polymer engineering background, Fortis3D's team of scientists and engineers created reinforced polyamide (PA, or nylon), and polyketone (PK) 3D printing filaments that are stronger and have lower glass fiber content than other filaments.

We found that most fiber-reinforced filaments on the market can produce relatively strong and stiff parts, but they are nowhere near as strong as the fiber-reinforced resins used for traditional injection molding," said Wayne Lam, Fortis3D's business manager. We also wanted to make high-strength materials available to a wider range of users than just those with expensive industrial machinery. With these two goals in mind, we developed these two materials to be the strongest on the market, allowing even users with mid-range printers to make very high-strength parts."

△ PA6GF moisture absorption diagram. Image from Fortis3D

Features of PA-GF20 and PK-GF20

Fortis3D's PA-GF20 and PK-GF20 shredded glass fiber reinforcements are used to 3D print high-performance functional parts. In addition to their excellent mechanical strength, both materials are chemically, high temperature, impact and abrasion resistant, making them durable in harsh environments. Applications for these materials range from industrial end-use parts to cover fixtures. Most other glass-reinforced filaments in the industry use very short (100-300µm) milled glass fibers that are incorporated into a variety of resins. While they have good strength and printability, they can be brittle. Chopped glass fibers are longer (3 mm) and provide very high strength while retaining more of the toughness of the base plastic material, but are more challenging to incorporate. Both types of fibers typically break down more during the compounding process, resulting in shorter fibers in the final product, so precautions must be taken during processing to minimize fiber breakage.

△ 3D printed part using PK-GF20. Image from Fortis3D

Technical data about PA-GF20 and PK-GF20 3D printing materials

Fortis3D's R&D team optimized the fiber loading and processing variables to produce one of the "strongest" fiber-reinforced PA filaments in the field with a lower glass fiber loading. The reduced glass fiber loading enhanced print performance, nozzle wear and surface finish. To achieve a high tensile strength of 78 MPa even after conditioning, the R&D team also used a chemical coupling agent to strengthen the bond between the glass fibers and the polymer matrix. With tensile strength retention in excess of 90% compared to injection molding, the material is tougher than other leading brands of glass fiber and carbon fiber reinforced nylon materials. 30% lower moisture absorption when using a nylon copolymer similar to Fortis3D's SnapPrint PA compared to typical PA6GF filament. Compared to PA6GF filament, stringing is minimized even when the filament is placed under ambient conditions.

△ Schematic diagram of moisture retention by number of days. Image from Fortis3D

Polyketone (PK) is a terpolymer of propylene, ethylene and carbon monoxide with characteristics similar to PA12, but with lower moisture absorption, higher chemical and impact resistance, and correspondingly less friction and abrasion. It also maintains mechanical strength after moisture absorption, unlike nylon. In terms of environmental protection, the polyketone production process produces 60% less CO2 than nylon production. However, it is very difficult to print alone due to excessive warpage and lack of adhesion to most bed adhesives and materials in PK printing. To solve this problem, Fortis3D's development team created a proprietary formulation that greatly reduces warpage and conforms to most bed materials with only PVA adhesive. Chopped glass fibers are added for strength and stiffness, making this material comparable to other carbon or glass fiber reinforced nylons in the industry without the risk of excessive moisture absorption. Moisture absorption is reduced by approximately 70% compared to typical PA6GF filaments, which means that stringing is limited and part strength is not compromised under week-long environmental conditions.

Fortis3D currently sells a line of filaments including SnapPrint PA, Lignum PLA, BioDuro Metallic PLA, etc. Fortis3D says its filaments are made from premium materials and each spool is restricted to strict quality control standards before shipment. According to Fortis3D, the company's manufacturing facilities are GMP-certified and registered to ISO 9001:2015 standards, ensuring "industry-leading" consistency in diameter, ovalness and color from batch to batch.