Soluble support material for PEEK – Why it matters.Agnieszka
Demographic changes and industry development generate increased demand and material consumption as well as the need to automate production. In this field, modern polymers – such as PEEK, support optimization, and in some cases replace the materials used so far.
The improvement in the use of plastics in the industry, which we can observe, increases the requirements for the measurement correctness and quality management. Valued in industrial applications – PEEK – is an excellent example of the benefits of innovation in the field of polymers, on the other hand, it is also an excellent example to illustrate the technological requirements that one must meet to make production reasonable.
PEEK, a high-performance, temperature-resistant semi-crystalline polymer is often used as a replacement for metals in a wide range of industrial end uses.
It has proved particularly useful in the production of transplant components, due to the possibilities offered by 3D printing technology for forming complicated, non-standard parts. The mechanical and physical properties of the material itself (high chemical resistance/acids, bases) allow avoiding inconvenience in the body environment caused by metal parts. High temperature and abrasion resistance enable efficient work in severe operating conditions, also with lubricants, which contributes to broader use in the automotive industry. On the other hand, low gas emissions, even when exposed to relatively high temperatures, enable its use in vacuum technology, in which light materials are sought that can meet the restrictive requirements of research in the space environment.
The conditions of thermal treatment during printing with PEEK can have a direct and indirect impact on its crystallinity and mechanical properties.
High strength, wear and thermal properties mean that the process of forming melted PEEK requires particular parameters of printing machines. The main difficulty in forming PEEK parts during additive manufacturing is the high melting point of this material, which means that models can be subject to a significant temperature change during forming. These changes may result in high internal stresses, warping and delamination.
Therefore, it is essential during printing PEEK material to maintain optimal conditions such as the temperature of the nozzle and heat treatment possibility, i.e. equipping the printer with a closed heated chamber and heated work table. Such actions have a positive effect on increasing the ultimate strength of the formed parts.
These parameters can directly affect the final crystallinity and mechanical properties such as tensile strength and modulus of elasticity. 3D printing with temperature control is of great importance in the design, setting and implementation of different degrees of crystallinity and mechanical properties for different parts of PEEK, even in different regions of the same piece.
For preventing deformations serve supporting structures systems that help to maintain given geometries and strengthen structures.
Technological parameters of printing with high-temperature materials mean that the support material should keep comparable temperature resistance. After the printing process is finished, the support is removed – most often mechanically – that may cause damage to the model.
To prevent damage during the mechanical removal of support structures, VSHAPER has introduced to the market specially designed for 3D printing technology, filament FS11 – a support material soluble in an alkaline aqueous solution. Easy to print – FS11, has features which have strong adhesion to model materials – which directly prevents its delamination. In addition to the work with models printed in PEEK, it can also be used when printing with PA, PC, ABS / PC, TPE, ASA, ABS or PET. Importantly, FS11 material dissolves in a mild alkaline solution, which, together with dissolved support material in limited quantities, can be removed directly via the sewage system.
The type of support material and the method of its removal is also of great importance for another reason. It is common to provide an air gap between the last support layer and the first layer of the model to facilitate mechanical removal of the support skeleton and avoid damage to the model. It allows to reduce the adhesion of both surfaces but requires some knowledge and additional work of the 3d printing engineer. This procedure is not necessary for soluble support materials.
The number of 3d printed PEEK elements applications will undoubtedly grow.
As you can see, working with demanding PEEK material requires advanced and technological preparation – its capabilities and the multitude of applications in the medical, automotive or aviation industry show how valuable this material is and make it worth knowing well – so professional preparation of the right environment for its processing will undoubtedly help in efficient and trouble-free 3d printing.