Toray Japan Announces New Release on March 28 Carbon fiber composite material molding process , not only can improve the dimensional accuracy of the components, but also reduce the energy consumption of the production process. After the technology is proven, Will be first applied to aircraft manufacturing, and then to the automotive and other general industry promotion.
Conventional CFRP parts are usually produced using an autoclave process. The prepreg is first laid in a mold and then fed into an autoclave for heating, curing, and forming. However, heat conduction is slow due to air as a medium, and if the mold itself has a heat capacity Larger, it absorbs a lot of heat, it will cause the parts themselves to heat up for a long time, and the molding speed is very slow. This has always been a headache for the experts in the industry.
Furthermore, once the size of the part to be formed is large, the thickness is considerable, or the geometry is complex, the problem of uneven distribution of residual stress inside the part may occur, resulting in easy deformation of the molded part. For example, in the assembly of an aircraft wing During the process, in order to avoid this situation, some fillers have to be added to pay extra manpower, material resources and time. These additional processes will further lengthen the entire production cycle.
In order to solve the above problem, Toray Japan has installed a predetermined number of heaters on the mold surface (dividing the mold surface into several heating zones) and performing contact heating under vacuum conditions. This method not only improves the heating efficiency, but also reduces the Energy consumption. Even more commendable is that each heater (heating zone) is independently controlled, applying the most appropriate temperature to the different parts of the part. This can achieve uniform distribution of the residual stress inside the part. It can get close to the pre-designed size and shape to the greatest extent, solves a series of problems that existed before, and reduces the manpower, material resources and time required for the assembly process.
In order to realize the goal of precise temperature control of different heating zones, Toray and Ehime University, Tokyo, Tokyo Institute of Technology Developed a simulation software that can predict component deformation and adjust the heating temperature accordingly. It shortens the time for component molding to the shortest and minimizes the size error. At present, the trial production equipment of this project is in place, and the experimental demonstration work is in order. Advancing.
If it is in accordance with the traditional autoclave molding process, it takes 9 hours to produce large-size CFRP aircraft parts. However, according to the new molding process developed by Toray this time, the production cycle can be shortened to 4 hours. In addition, the new process can save 50% of energy consumption. (Because of the direct contact heating method, the heating/pressurizing medium is eliminated), the dimensional accuracy can be improved, the amount of filler can be reduced, and the man-hour for assembling can be shortened.