The idea of the 3D printed engine first came up during the consultation with the engineers of Audi Hungaria, and its development started in 2016 in close cooperation. Our main aim was the examination of the manufacturing technology of 3D printing and its use in the automobile industry, as well as researching development potentials. To achieve this aim we had the Experimental Engine Manufacturing Center of Audi Hungaria Zrt. for our help and the metal 3D printer they use, which was developed by SLM Solutions AG. The basis of the unit being the subject of the research was the EVO4 engine construction developed and assembled by our team earlier, and its parts were modified according to the needs of the printing technology.
The cylinder, the cylinder head, the whole crankcase, and all the lids, which cover the engine are composed of 3D sintered aluminum parts. After printing all parts went through CNC processing. It was followed by hand finishing in order to avoid problems that might come up during the assembly, such as concerning the surfaces of the combustion chamber, the intake and exhaust manifold, and the inner surfaces which contact with oil. First, we carried out component tests by parts because the engine was compatible with the machined parts, then we tested the assembled one on our test bench. In order to decrease the load, a spare application was written for the engine, so in the end, it was calibrated for 50 horsepower. The biggest components of the internal combustion engine were created with a more favorable and effective manufacturing technology, whose additional advantages are a better material structure, mass, and cost efficiency at the examination of unique, prototype parts. Besides thanks to laser sintering, there is an opportunity to try out part designs different from traditional constructions during the creation of complex geometries.
In race engine development the quick and efficient testing of the different unique component constructions is a very important aspect, which, thanks to 3D printing, grants a more free, economical, and time-efficient implementation in the automobile industry as well. The 3D printed internal combustion engine of SZEngine is a good example of the popularization and applicability of the technology because after the successful tests we had the opportunity not only to exhibit but also to prove the use of our engine and the 3D printer technology in working condition during a presentation in a Formula Student East competition.