However, additive manufacturing technology has relatively high requirements for raw materials, resulting in high raw material costs. At the same time, the equipment for additive manufacturing is relatively expensive, and some key components also rely on imports, which limits the application of this technology in ordinary products. Developing low-cost raw materials and mastering key technologies to reduce equipment costs are important issues to be addressed in promoting additive manufacturing technology.
Femtosecond laser technology is composed of chemical lasers that operate freely and rapidly in various forms of laser electromagnetic waves or laser pulses. Its processing duration is very short, and it has very high instantaneous motion speed and processing power. During the processing, laser can easily and directly achieve fine laser processing, repair, and laser microwave diffraction treatment of any material. Laser interacts with other chemicals in an extremely short duration of fine processing and a very small action space. The laser temperature within the action time range rapidly rises in an instant, and the femtosecond laser spot is removed by various forms of laser plasma rapid outward movement and spraying.
The femtosecond laser technology avoids the quality problems caused by the high-temperature fusion and melting process in traditional processing, significantly reducing and effectively eliminating many other negative impacts that may arise from the high-temperature thermal effects in traditional processing management. It has great application prospects in the field of ultra fine machining and repair.
The femtosecond laser technology is still in its early stages, and the development and application of this technology still need to solve a series of key technical problems. For example, there is currently no complete theory to explain the physical essence of the interaction between laser and matter under extreme conditions of ultrafast, ultra short, and ultra strong; Increase investment in the production of femtosecond lasers and microfabrication systems, and further miniaturize their volume; Improve the working environment for its microfabrication and extend its lifespan; Develop software for model design based on the characteristics of femtosecond laser microfabrication and the properties of the processed material, simulate and simulate the machining process, and achieve optimal parameter machining.
3、 Ultrasonic machining technology
Ultrasonic machining is a special machining method that uses ultrasonic frequency as a tool for small amplitude vibration, and gradually breaks the surface of the workpiece material through the hammering effect of the abrasive free in the liquid between it and the workpiece on the machined surface. It has unique advantages in cutting, wire drawing dies, deep and small hole machining, and other fields. Ultrasonic machining has experienced rapid development in the past few decades, especially in the field of difficult to machine materials, where many key process problems have been solved and good results have been achieved.
Ultrasonic machining has gradually become an important means to improve the energy efficiency of mechanical processing. From the perspective of application industry, ultrasonic machining is currently mainly applied in 3C, aerospace, national defense and military industry, and 5G new materials. In the aerospace field, high product quality is required. Important materials such as carbon carbon composites and carbon fibers have excellent characteristics such as high strength, low density, ultra-high temperature resistance, and corrosion resistance. However, their high strength, high elastic modulus, and wear resistance are difficult to process, and are not easy to cut, prone to edge collapse, and have fast tool wear. Ultrasonic machining can reduce tool load, improve edge and burr phenomena, and improve machining quality and efficiency.
With the improvement of processing quality and demand for new materials, difficult to machine materials, difficult to machine structures and surfaces, as well as the combination of ultrasonic machining with electrical discharge machining, electrochemical machining, cutting machining, grinding machining, etc. to form composite machining, ultrasonic machining will have broader application prospects in improving processing efficiency and quality.