In fact, some masks are made of ultrasound

We can hear a variety of sounds from around every day, but when the sound wave frequency exceeds 20,000 Hz (Hz), we can't hear it again. This sound waves are called ultrasonic. Ultrasound has the same essential attributes as the sound we hear daily, and the difference is that the frequency is different. When the ultrasonic spread has the advantages of strong direction, energy easy concentration, and large communication displacement. And ultrasound is not far away from our daily life. Some of our daily masks are made of super -raw waves.

Ultrasound positioning diagram

"Super Audio" in nature

Since we can't hear the ultrasound, how can we find ultrasonic? This has to tell this little story: a scientist named Razaro Spalali found that bats can still fly and prey flexibly in the night, so they did a series of experiments on the bat: blindfolded the bat The eyes, the nose of the bat, and the paint on the bat body, but did not affect the bat ability of the bat. In the end, when the ears of the bat were blocked, the bat could no longer fly freely, becoming four bumps, and quickly landed on the ground. Spalapril understood that the bat "observed" the environment by sound to avoid obstacles. The bat uses ultrasonic operations at night through in -depth research. People find that the bat can emit extremely high -frequency ultrasonic through the throat. Ultrasonic waves are quickly spread along a straight line. After encountering an object, the lights of the flashlight are reflected on the mirror. And its ears can receive the ultrasonic signal that human ears cannot receive. Bats depend on such ultrasonic waves that humans cannot hear in the night. There are not only bats in nature, but also other ultrasonic masters. Dolphins can use the airbags under their breathing holes to emit ultrasonic waves. The ultrasonic waves feedback from the fish group are predatory information. Similar ultrasonic waves can be used to communicate. The ultrasonic feedback from obstacles can be used to detect the surrounding environment information. In addition, there are many animals that can emit ultrasound or hear ultrasonic, such as elephants, jellyfish, etc. Scientists imitate the ultrasonic phenomenon in nature and send an ultrasonic signal with ultrasonic equipment. When the signal encounters other objects in the dissemination medium, it will return. The time interval and orientation of the receiving record feedback can measure the orientation and distance of the target. Scientists are designed according to this principle.

"Ultrasound" scientific pioneer team

With the rapid development of science and technology, ultrasonic technology is getting closer and closer to people's lives, and the scope of use is becoming more and more wider. In the military field, submarines imitate dolphins, and to detect underwater combat targets through ultrasonic systems from the sonar system on the submarine. Ultrasound is extremely small in liquid, and long -distance monitoring can also be achieved in the deep sea where the five fingers are not visible. It is by far the most effective deep -sea detection method. In addition, ultrasonic waves are also applied to weapons. High -frequency sound waves launched by ultrasonic weapons can cause strong air pressure to a certain extent, and cause physiological reactions such as blurred vision and nausea. In the field of scientific research, there is a new material called amorphous alloy. A amorphous alloys are prone to crystallization and oxidation during resistance welding. At this time, ultrasonic welding reflects its outstanding advantages. The traditional welding process needs to rely on high temperature melting to achieve the combination of two workpieces. When using ultrasonic waves for welding, as long as a certain pressure is maintained, the ultrasonic continuous vibration is used to make the welding up and down upper and lower up and down. The workpiece produces friction and deformation to increase the temperature at the binding surface. This technology realizes the solid welding that does not melt, and effectively avoids the splash and oxidation phenomenon generated during the resistance welding. Using ultrasound to check whether the steel plate is defective in the latest high -end smartphones, the amorphous alloy is used as a hawk hinge for the screen rotation structure, which shows the special feature of the material. Researchers have recently discovered that using ultrasonic technology can achieve room temperature manufacturing and molding of amorphous alloys, completely breaking through its traditional manufacturing and molding methods, which has attracted widespread attention from scientific researchers in the field.

Ultrasound figure on the front line of resistance

The new crown virus is still raging around the world. Mask is an indispensable medical supplies that block the path of virus transmission, and it has become a hard currency in various countries. The KN95 mask consists of 5 ~ 6 tensile filtration cloth, nose bridge, and ear strap. In the mask production, ultrasonic welding technology is part of the core component of the KN95 mask automation production line. The KN95 mask automation production line is composed of non -woven filter cloth feed mechanism, nasal bridge ultrasonic welding mechanism, ears ultrasonic welding mechanism and mask folding mechanism. Taking the ear strap welding mechanism as an example, it uses the high -frequency vibration transmission of ultrasonic transmission to rub the ear strap of the mask to the surface of the non -woven filter cloth to produce a local high temperature, which makes the non -woven filter cloth melt and the ear strap melt. After the ultrasound stops, continue to maintain the pressure for a certain period of time so that the connection is solidified, so that the intensity of welding can be close to the strength of the raw material. In addition, the sturding, edge, and nose bridge on the KN95 mask are completed by the ultrasonic welding process. You may wish to take a mask to touch the connection and feel the actual results of the ultrasonic welding technology.

This article comes from the magazine of "Knowledge is Power". The original title "The Mystery of Ultrasonic: Unexpectedly, But to Explore the World", author Yang Jian, Ma General, deleted and modified. Please indicate the source of the original work.

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