Carbon Fiber Reinforced PPS As Alternative To PEEK

Industrial applications for engineering thermoplastics such as PC and high performance thermoplastics such as PEEK are growing. In 3D printed filament form, these materials offer a lightweight alternative to metals such as steel and aluminum in industries such as aerospace and energy. Reinforcing these high-performance plastics with additives can further improve their performance. For example, short-cut carbon fibers add strength and stiffness and can be added to low to mid-priced engineering plastics as well as high-performance plastics. As long as the 3D printer nozzle can handle abrasive materials, these composites can be printed just like regular thermoplastics. The main drawback to high-performance composites, such as reinforced PEEK, is the high cost of the required 3D printing hardware. These materials require extremely high extrusion and chamber temperatures, and the price of the right hardware (often in the six-figure range) often offsets the overall cost benefits of plastic 3D printing technology.

What is PPS?

Polyphenylene Sulfide (PPS) is a semi-crystalline thermoplastic that can be categorized as a high-performance plastic along with materials such as PEEK and PEI.Widely used in machining, molding, and additive manufacturing, PPS has good mechanical properties, high temperature resistance compared to standard and engineering thermoplastics, and is flame retardant. Its most desirable property, however, is its excellent chemical resistance: PPS is resistant to many acids, bases, solvents, and some strong oxidizing agents (under certain conditions). For strong oxidizers like chlorine dioxide, coatings or linings may be required. Due to its desirable properties and favorable price compared to PEEK, PPS has a wide range of applications in various industries. Its mechanical and chemical properties make it useful in automotive, energy and chemical processing, while its flame retardancy and self-extinguishing properties make it the material of choice for electrical and electronic components such as SMT devices, motor housings and transistor seals. Not only impressive from a thermoplastic standpoint, PPS is often used as a true alternative to metals such as steel and aluminum. Its thermal stability and excellent chemical resistance allow it to be used in harsh chemical environments, while its resistance to corrosion and the effects of automotive fluids is remarkable.PPS as a composite materialIn order to increase strength and stiffness, PPS can be reinforced with additives such as short-cut carbon fibers or glass fibers to form composites. In fact, PPS is more commonly sold as a "filled" material than unfilled. According to the researchers, "The addition of carbon can significantly improve the mechanical properties, tribological properties, post-fire structural integrity, and electrical/thermal conductivity of ......PPS blends and composites."

Carbon fiber-reinforced PPS can be used in applications similar to unfilled PPS. However, the improved mechanical properties make it a suitable material for components such as tools, jigs and fixtures.PPS composites are particularly well suited for industrial FFF additive manufacturing, as these 3D printers are unable to print materials like pure carbon fiber.

3D Printing PPS

PPS, both unfilled and in composite form, offers a fairly viable way to 3D print high-performance thermoplastic parts. This is made possible by its print temperature of around 320°C, which is high but not extremely high.

While an extrusion temperature of 320°C is beyond the capabilities of most FFF 3D printers, it is significantly lower than the ~400°C required to 3D print PEEK. (PEEK also requires very high chamber temperatures.) As a result, PPS parts are less temperature resistant than PEEK parts, but they can still be used in demanding applications up to ~230°C. The type of 3D printer needed to print PPS is somewhere between an industrial grade FFF printer and a specialized high temperature FFF printer. Reliable production-grade printers cost around $10,000, while state-of-the-art high-temperature machines like the Stratasys Fortus 450mc cost around $150,000, which can be prohibitively expensive for SMBs. When printing carbon fiber-reinforced PPS, the durability of the printhead must be considered in addition to the temperature, as the short-cut fibers are more abrasive than the thermoplastic substrate and can therefore damage plain brass hardware. a suitable build surface for PPS is PEI sheet, with the print bed heated to approximately 80°C. For complex 3D printed PPS parts printed on dual extruders, the material is compatible with the PVA backing material. 3D printed PPS reinforced with carbon fiber is suitable for applications such as functional prototyping, tooling for molding and other processes, and manufacturing aids such as fixtures. Industries using reinforced PPS filaments include automotive, railroad, and aerospace. New high-performance, low-cost additive manufacturing systems are enabling more users to 3D print with PPS. For example, the UltiMaker Factor 4, which begins shipping in May 2024, features a highly abrasion-resistant print core capable of printing at temperatures up to 340°C - enough to print carbon fiber-reinforced PPS and many engineering thermoplastics. Modern systems like the Factor 4 are unique in that they are positioned in the middle market. Despite its ability to print truly high-performance materials like carbon fiber-reinforced PPS, the Factor 4 is priced more along the lines of a typical professional-grade desktop 3D printer than a high-temperature PEEK 3D printer. To meet the needs of users in industries such as electronics and automotive, UltiMaker has also developed its own composite material, UltiMaker PPS CF, specifically for use with the Factor 4. The material offers consistent flow and ideal material properties, formulated to deliver high performance and ease of printing. The combination of printer and material also achieves excellent dimensional accuracy with minimal shrinkage compared to PEEK. Like other carbon fiber PPS materials, UltiMaker PPS CF is highly recommended for functional prototyping and indirect manufacturing of components, but its excellent chemical and heat resistance opens the way for a wide range of applications, including end-use parts. UltiMaker-formulated PPS-CF is flame-retardant (V0-94) and guarantees low warpage on large parts, making it a good match for other PPS CF filaments. UltiMaker-formulated PPS-CF is flame retardant (V0-94) and also guarantees low warpage on large parts, differentiating it from other PPS CF filament suppliers.

The main application components are:

Air transportation fasteners

This bracket is used to securely fasten air cargo or to safely load components in an airfreight package. It must therefore be temperature-resistant, very robust and stable, and resistant to chemicals - application requirements can all be met with PPS CF. Another advantage of additive manufacturing is that the design can be adapted iteratively and, thanks to the materials used, all iterations can meet the necessary certifications.

High-pressure pump valves

This type of pump valve is installed in trains that transport liquids or chemicals. However, as it has become an obsolete component (no longer in production), the entire pump assembly needs to be replaced at a cost of around €5,000. Using PPS CF, it can now be 3D printed, so it still meets the UL94 V0 standard for non-flammability and can also be used with hot acids.

Sensor bracket

This simple bracket is used on production lines and around the field to quickly mount sensors, cameras or other necessary extensions. Prioritize components to withstand extreme loads when used outdoors, including weather conditions, impact resistance or fire conditions

New possibilities

Carbon fiber reinforced PPS is a high performance material for some of the most demanding industrial applications. Some end users of additive manufacturing may believe that they need the most expensive materials and hardware to achieve engineering-grade quality and a high level of design freedom. However, UltiMaker Factor 4 and its specially formulated PPS CF materials show that this is no longer the case.

New possibilities

Carbon fiber reinforced PPS is a high performance material for some of the most demanding industrial applications. Some end users of additive manufacturing may believe that they need the most expensive materials and hardware to achieve engineering-grade quality and a high level of design freedom. However, UltiMaker Factor 4 and its specially formulated PPS CF materials show that this is no longer the case.