Metals And Amorphous Alloys

The atoms are arranged in topological disorder in three-dimensional space, without long-term periodicity, but within the range of several Atomic spacing, the arrangement of atoms still has certain rules, so it can be considered that the atomic structure of amorphous alloys is "long-term disorder, short-term order". It is generally defined that the short-range order region of amorphous alloys is less than 1.5 nm, that is, no more than 4-5 Atomic spacing, which distinguishes them from nanocrystals or microcrystals=short-range order can be divided into chemical short-range order and topological short-range order. Crystals are typical ordered structures, while gases, liquids, and amorphous solids belong to disordered structures. Amorphous solid materials also include types such as amorphous inorganic materials (such as glass), amorphous polymers, and amorphous alloys (also known as metallic glass).

The ability of metals to produce amorphous states has always been a difficult problem that modern scientists have focused on deciphering. Scientists have found that after melting, the internal atoms of metals are in an active state. As soon as the metal begins to cool, the atoms will slowly and orderly arrange according to a certain crystal state pattern as the temperature decreases, forming crystals. If the cooling process is fast and the atoms are solidified before they can rearrange, amorphous alloys are produced. It can be seen that one of the key technologies for producing amorphous alloys is how to quickly cool them. The preparation of amorphous alloys adopts a rapid solidification process. Spray high-temperature molten steel into a high-speed rotating cooling roller. The steel rapidly cools at a rate of millions of degrees per second, reducing the temperature of 1300 ℃ steel to below 200 ℃ in just one thousandth of a second, forming amorphous strips.

Developed countries have always strictly implemented technological lockdowns on the manufacturing technology of amorphous alloys. After nearly 20 years of unremitting efforts, Chinese scientists have finally achieved technological breakthroughs in the preparation of amorphous alloys during the "Ninth Five Year Plan" period, mastering core technologies with independent intellectual property rights. And breakthroughs have been made in the industrialization of amorphous alloys, forming an industrial scale with an annual output of 4000 tons. It fills a technological gap in China's metallurgical industry. Amorphous alloys have undergone significant changes in physical, chemical, and mechanical properties compared to crystalline alloys. Take the amorphous alloy dominated by iron as an example, it has the characteristics of high saturation Magnetic flux density and low loss. Modern industry often uses it to manufacture distribution transformer cores. At present, China is able to produce amorphous strips of different specifications according to market needs, with a brightness of up to 220mm. Compared with traditional silicon steel core transformers, transformers made of this amorphous alloy have a 60% to 80% reduction in no-load losses, which has a significant energy-saving effect. If all the existing distribution transformers in China are replaced with amorphous alloy transformers, 9 billion kilowatt hours of electricity can be saved for the country every year, which means that a 1 million kilowatt Fossil fuel power station can be built less every year, 3.64 million tons of coal can be reduced, and more than 9 million cubic meters of carbon dioxide and other exhaust emissions can be reduced. In this sense, amorphous alloys are known as "green materials" by people.