Source: China Aerospace News
It is understood that on May 5th, China Aerospace Science and Technology Group Co., Ltd. made a successful first flight of the Long March 5B carrier rocket developed by the General Manager. During the same period, the full 3D printed core-level binding support developed by the 211 Factory of the First Academy passed the flight assessment . The binding support is a key product that connects the rocket core stage and the booster to transmit the huge thrust of the booster. It carries more than 200 tons of concentrated force during flight. This is the 3D printing product in the aerospace field that has concentrated on the most “bad” environment to date. It also marks that the 211 plant’s strength in another additive manufacturing technology has leapt to the forefront of the country.

In the development process, in order to greatly reduce weight, the designer optimized the key bearing component of the binding support system, and finally selected the titanium alloy component designed with the optimal force transmission path, which can effectively reduce the weight by 200 kg.
However, the key load-bearing parts of titanium alloy manufactured by traditional methods cannot meet the needs of models due to their machinability, consistency of organizational performance, and manufacturing cycle. To this end, the model team used 3D printing technology for the first time to develop this main bearing. Facing the parts with large size, high precision and high performance, 211 Factory Additive Manufacturing Center abandoned the usual 3D printing scheme and chose full 3D printing with higher technical difficulty in order to ensure the overall product quality and reliability. At the same time, in order to further improve the performance of the product, the center chose a method far more difficult to control, which is far away from the equilibrium forming method.
After nearly 4 months of technological exploration, the additive manufacturing center solved the problem of large-size parts forming and easy cracking, and successfully developed the first full 3D printed core-level binding support product in March 2018. Subsequently, the center accelerated the engineering application process, fully mastered the key technology of the whole process manufacturing, and the products passed the comprehensive ground assessment of 300 tons and 400 tons, which fully verified the reliability of the products and met the conditions for batch production. In March 2019, the official product delivery.
The product performance test results show that the fully printed titanium alloy material is slightly better than the static load yield strength, and the elongation is far better than the domestic engineering application level in the same period. The strong plastic product is more than doubled, and the dispersion of the cutting performance of the whole product reaches the level of forgings Claim.
It is reported that the 211 factory will continue to improve the batch production efficiency of this product and promote the application of this technology in the large-scale centralized power transmission mechanism of future aerospace models.