What is amorphous alloy?1

Let's start with amorphous materials. There are generally two kinds of materials that people come into contact with in daily life: one is crystalline material, and the other is amorphous material. The so-called crystalline material means that the arrangement of atoms inside the material follows a certain rule. On the contrary, if the internal atomic arrangement is in an irregular state, it is an amorphous material. Generally, metals whose internal atomic arrangement is ordered are all crystalline materials.

Scientists have discovered that after the metal is melted, the internal atoms are in an active state. Once the metal begins to cool, the atoms will slowly arrange in an orderly manner according to a certain crystalline law as the temperature drops to form crystals. If the cooling process is fast, the atoms will be solidified before they can be rearranged, resulting in an amorphous alloy. The preparation of the amorphous alloy is a rapid solidification process. The high-temperature molten steel in the molten state is sprayed onto the high-speed rotating cooling roll. The molten steel is rapidly cooled at a rate of one million degrees per second, and the molten steel at 1300°C is reduced to below 200°C in only one thousandth of a second to form an amorphous strip.

Compared with crystalline alloys, amorphous alloys have undergone significant changes in physical, chemical and mechanical properties. Taking iron-based amorphous alloys as an example, it has the characteristics of high saturation magnetic induction and low loss. Due to such characteristics, amorphous alloy materials have a broad application space in many fields such as electronics, aviation, aerospace, machinery, and microelectronics. For example, in the aerospace field, it can reduce the weight of power supplies and equipment, and increase the effective load. Used in civil power and electronic equipment, it can greatly reduce the size of the power supply, improve efficiency, and enhance anti-interference ability. The miniature iron core can be used in a large number of transformers in the integrated service digital network ISDN. Amorphous strips are used to make sensor tags for anti-theft systems in supermarkets and libraries. The magical effect of amorphous alloys has broad market prospects.