Abstract: Ultrasonic technology is widely used in industry. This paper will introduce the principle of ultrasonic cutting, and combine the examples of specific electronic products to compare the effects of mechanical cutting and laser cutting, and study the application of ultrasonic cutting technology.
Ultrasonic cutting is a high-tech technology for cutting thermoplastic products. Ultrasonic cutting technology uses ultrasonic welding to cut workpieces. Ultrasonic welding equipment and its components are also suitable for automated production environments. Ultrasonic cutting technology is widely used in commercial and consumer electronics, automotive, new energy, packaging, medical, food processing and other fields. With the rapid development of the domestic economy, the application range will become wider and wider, and the demand in the market will further increase. Therefore, ultrasonic cutting technology has great development prospects.
· Mechanical cutting
Mechanical cutting is the separation of materials by mechanical means at normal temperature, such as shearing, sawing (saw saw, wafer saw, sand saw, etc.), milling and so on. Mechanical cutting is a common method of roughing materials and is a cold cut. The essence is that the material to be processed is squeezed by the scissors to undergo shear deformation and to reduce the separation process. The process of mechanical cutting can be roughly divided into three consecutive stages: 1. elastic deformation stage; 2. plastic deformation stage; 3. fracture stage
· laser cutting
3.1 Principle of laser cutting
Laser cutting uses a focused high-power-density laser beam to illuminate the workpiece, heating the material to thousands to tens of degrees Celsius in a very short time, allowing the material to be irradiated to rapidly melt, vaporize, ablate, or ignite, while using the beam The coaxial high-speed airflow blows off the molten material, or the vaporized material is blown away from the slit, thereby cutting the workpiece to achieve the purpose of cutting the material. Laser cutting is one of the hot cutting methods.
3.2 Laser cutting features:
As a new processing method, laser processing has been widely used in the electronics industry due to its advantages of accurate, fast, simple operation and high degree of automation. Compared with the traditional cutting method, the laser cutting machine is not only low in price, low in consumption, and because the laser processing has no mechanical pressure on the workpiece, the effect of cutting the product, the precision and the cutting speed are very good, and the operation is safe and the maintenance is simple. Features such as: The shape of the product cut by the laser machine is not yellow, the automatic edge is not loose, no deformation, no hard, the size is consistent and accurate; can cut any complex shape; high efficiency, low cost, computer design graphics It can cut any size lace in any shape. Fast development: Due to the combination of laser and computer technology, users can design laser engraving output and change the engraving at any time as long as they are designed on the computer. Laser cutting, because the invisible beam replaces the traditional mechanical knife, the mechanical part of the laser head has no contact with the work, and it will not scratch the working surface during the work; the laser cutting speed is fast, the incision is smooth and flat, generally no need Subsequent processing; no mechanical stress in the incision, no shear burr; high processing precision, good repeatability, no damage to the surface of the material; NC programming, can process any plan, can cut the whole plate with large format, no need to open the mold, economical save time.
· Ultrasonic cutting
4.1 Ultrasonic cutting principle:
With the special design of the welding head and the base, the welding head is pressed against the edge of the plastic product, and the ultrasonic vibration is used to cut the product to achieve the cutting effect by using the ultrasonic vibration working principle. As with traditional processing techniques, the basic principle of ultrasonic cutting technology is to use an electronic ultrasonic generator to generate ultrasonic waves of a certain range of frequencies, and then the original amplitude and energy are small by an ultrasonic-mechanical converter placed in the ultrasonic cutting head. The ultrasonic vibration is converted into mechanical vibration of the same frequency, and then amplified by resonance to obtain a large enough amplitude and energy (power) to meet the requirements of cutting the workpiece. Finally, the energy is transmitted to the welding head, and then the product is cut. The advantages of the slit are smooth and not cracked.
Ultrasonic cutting vibration system is mainly composed of ultrasonic transducer, ultrasonic horn and welding head. Among them, the function of the ultrasonic transducer is to convert the electrical signal into an acoustic signal; the horn is an important component of the ultrasonic processing equipment. It has two main functions: (1) energy-concentration—that is, the mechanical vibration displacement or velocity amplitude is amplified, or the energy is concentrated on a smaller radiation surface for energy gathering; (2) the acoustic energy is effectively transmitted to the load— As a mechanical impedance converter, impedance matching is performed between the transducer and the acoustic load to allow ultrasonic energy to be transmitted from the transducer to the load more efficiently.
4.2. Features of ultrasonic cutting:
When the ultrasonic wave is excited to reach a higher temperature, the product melts due to high temperature intermolecular excitation and internal friction.
Ultrasonic cutting features. Ultrasonic cutting has the advantages of smooth and firm incision, accurate cutting, no deformation, no warping, fluffing, spinning, wrinkling and so on. Avoidable “laser cutting machine” has the disadvantages of rough cutting, focal edge, pilling, etc. The advantages of ultrasonic cutting include: 1. Fast running speed, with a typical cycle time of less than one second. 2. The plastic parts are not stressed; 3. The cutting surface is clean; 4 Many places can be cut at the same time for automatic separation 5 Ultrasonic cutting is non-polluting.
What type of material is being cut using ultrasound? The best work for rigid thermoplastics (polycarbonate, polystyrene, ABS, polypropylene, nylon, etc.). They pass mechanical energy more efficiently. Lower stiffness (modulus of elasticity) thermoplastics such as polyethylene and polypropylene absorb mechanical energy and can give inconsistent results.
Compared with the effects of mechanical cutting, laser cutting and ultrasonic cutting, ultrasonic is more suitable for cutting the ear of the product, and the effect is good, meeting the requirements of product cutting, and the efficiency of ultrasonic cutting is the highest. Ultrasonic cutting is a good solution to the requirements of product cutting.
With the gradual deepening of research on ultrasonic cutting technology, it is believed that in the near future, it will be more fully applied.