Three-dimensional printing technology soon will not surprise anyone: according to the trends and loud reports of the developers, it will be possible to print everything as it seems by the additive methods in the near future - from the tie to the human kidney. 3D-printing of manufactured articles made of composite materials does not look like something considerable in this range. Nevertheless these technologies received a little attention in a worldwide list of industrial technologies, therefore, consortium of Russian scientists and engineers-innovators has taken over the project to get ahead of potential competitors.
The consortium includes the developers of the Skolkovo Institute of Science and Technology, Tomsk Polytechnic University, RAS Institute of Problems of Mechanical Engineering, NITU "MISiS" and SB RAS Institute of Physics of Strength and Materials Sciences. The main work on the creation of specialized "software" was charged to the employees of Engineering center of Peter the Great St. Petersburg Polytechnic University. Aleksandr Nemov, deputy director of the Centre and the young leading specialist of the "Computational Mechanics" laboratory told more on the new production technology of composites area and the tools for the design of composite products.
- Our task is divided in two the hardware and the software. Creating equipment and the direct production of composite materials by additive method currently is conducted by Skolkovo Institute of Science and Technology.
We are developing the methods, algorithms and software in the engineering centers, that will allow designing the composite structures that are optimized for the operating conditions of particular products.
Of course, these two lines are parallel: it is possible to design a composite structure on your own, without equipment, but very few people want it itself, if there is no opportunity to make it. Therefore, the creation of equipment for the production of composite structures, with broad capabilities in terms of form design and its composite microstructure is an integral part of the project.
Is it supposed that 3D-printing of composites or the process of creating the product will be something like an assembling of meccano?
- This is a real layered printing.
The extruder has already been designed and manufactured by the Skolkovo Tech for the production of composite by additive method. It is supplied with carbon fiber and some binder, a plastic, which is blended with the fiber in the molten state in the extruder.
About 130 samples have appeared thanks to using this equipment, and consortium members have already conducted tests - on the thermal properties, mechanical properties and chemical resistance to a variety of solvents, as it is the requirement of our industrial partner. The experimental results showed that a serious work on the mechanical properties should be done, but the first conclusions are positive on the whole, as we have constructive ideas to improve the physical and mechanical properties of the samples. A first scientific article on the project has already been published.
Is there 3D-printing of composites technology abroad?
- Additive manufacturing of composite materials is on the cutting edge of technology now. There are organizations working in this area in the world, but industrial analogues with impressive results have not yet been created.
Therefore we can say that we are on the cutting edge, and we believe that our project consortium has all the necessary competence to solve the technological problems.
What has already been done in the St. Petersburg Polytechnic University in the "program" direction of work?
- We have conducted extensive work on the analysis of existing software: there are many successful commercial systems for computerized design, computerized engineering (CAE-systems) and for solving the optimization problems on the market now, but there is no such a tool that would allow design engineers to fully design composite products, including their microstructure, optimized for specific operating conditions. We found some of the strengths of the different software, so we want to build a system that integrates these forces. Why should we reinvent the wheel if some individual problems have already been successfully solved?
ANSYS, DS SIMULIA Abaqus, HyperWorks and LSTC LS-DYNA engineering software have many opportunities to work with composite materials and composite structures, and it is possible that we will apply something from these world-class CAE-systems. In addition, in the first phase, we have developed a multi-level model of composite materials for virtual testing.
The industrial partner of the project is the "United Rocket and Space Corporation". But surely this industry is not the only field of developments application, is it?
- It is, so to say, the primary application area. The very idea of ??our system is invariant to the industry. ACCD is ready to support us, so we promote our development together. The terms of reference provide several elements specifically for ACCD - power, mounting structures. But in general, the software system being developed is multi-purpose one. We want to enable it to design a wide class of products of certain requirements: dimensional constraints, loads they must withstand, the requirement of weight minimizing, etc.
In rocket and space technology the optimization objective is most often to minimize the weight of structures and equipment, as the fight is for every extra kilogram of the payload.
In the current project we plan to develop a system for the maximum size of manufactured composite structures up to three meters. That is we are not threatened the ten meters dimensions, because we want to fill a specific niche in the process equipment: machines for automated calculations of composite materials are usually designed for large-sized construction of tens of meters, and in the size range less than a meter additive technologies have already well proven. Of course, we are not talking about composite materials. We want to fill the «gold mean»: our size is from half to three meters.
Will the 3D-printer for composites completely replace the existing technology of production of such materials?
- Today, we do not undertake to say that with the new integrated system we will produce all the products of better quality than now exist for any industry. But the main advantage of our development is its flexibility, the ability to customize the creation of different microstructures in different areas of the composite structure. How the composite materials are designed most often? The designer has a set of technologies available to him. For example, he may use only the vacuum infusion method, and he has a set of tissues for production of carbon fiber construction. He choose from them where and which fabric should be placed, where and how many layers he should set up. It is clear that it is not the fact that such a structure and design of product will be optimal from a particular point of view. The idea of ??the project is to learn how to design and create the optimal composite structures. And not only virtually.
The project "Development of an integrated system of computer-aided design and engineering for the additive production of light and reliable composite structures of key high-tech industries" is being implemented with the financial support of the Ministry of Education and Science of the Russian Federation (Federal Target Program "Research and development in priority areas of scientific and technological complex of Russia for 2014-2020 years ").