3D printing of jet engines from metal is what we love about 3D metal printers. Turbojet engines are a combination of high technology, modern heat-resistant materials, and extreme loads. This engine was printed on a 3DLAM Mid2019 3D metal printer commissioned by Microjet (microjet.su). According to the NDA, we can't show what is inside because the parameters of the combustion chamber and engine layout are a commercial secret, but we can tell you about it.
Inside the of the body of the jet engine there is a heat chamber, remember that the engine is printed from an analog of the heat-resistant alloy Inconel 718 with a melting point of 1260-1335°C and operating temperature up to 700°C. The engine walls, which are 0.8 mm thick, have channels for oil and fuel. Separate channels are provided for front and rear bearing lubricants and a separate fuel channel for the spark plug. The applied technology of layer-by-layer selective laser melting allowed to obtain channels with a diameter of 0.6 mm with a length of 200 mm passing through the entire engine, both vertically and horizontally. At the engine outlet, there is a straightening device to increase the efficiency of the turbine and the overall efficiency of the engine. Thanks to fine-tuning of the 3D metal printing process, the 3DLAM Mid2019 3D printer can grow blades with an angle of up to 30 degrees without using supporting structures. Eliminating supports structures when printing a straightening device increases the efficiency of the engine by 4-6%.
The total weight of the engine is 700 grams, which is 200-300 grams lighter than the classic layout from multiple parts. The use of 3D metal printing reduces the total number of engine parts by two times. This simplifies the design of the engine, significantly reduces the amount of documentation, and increases the reliability of the product. 3D printing with metal reduces the cost of manufacturing and operating micro turbojet engines. The printing time is 25 hours. The time for receiving the finished product by the customer from the moment of receiving the final 3D model was 34 hours.
The video showing the process of extracting jet engine from the powder at the end of the 3D metal printing process