'High-end bearings rely on imports, why can't we make them ourselves?' After investigating six provinces including the three provinces of Northeast China, Zhejiang and Shandong, Wang Dongsheng, executive deputy director of the Shandong Technology Transformation Center of the Chinese Academy of Sciences, found the answer-the biggest question Out of the material. 'Without good steel, high-end bearings can never be made.'

In the manufacturing industry, there is a saying, 'Any place that rotates needs to use bearings.' As an indispensable core component in mechanical equipment, bearings support the mechanical rotating body, reduce its friction coefficient, and Ensure its rotation accuracy. Whether airplanes, automobiles, high-speed rails, or high-precision machine tools, instrumentation, rotating parts, all need the support of bearings.

It is not an exaggeration to say that the bearings in the engine have been working in 'purgatory' ——It not only has to run for a long time at a speed of tens of thousands of revolutions per minute, but also endure various forms of stress extrusion, friction and ultra-high temperature. This raises the bearing’s accuracy, performance, life and reliability. Requirements, and the key factor that determines these four points lies in its material.

The manufacture of bearings requires very harsh conditions, a very complex manufacturing process and excellent quality steel. After decades of hard work, China’s shaft-making technology is close to the world’s top level, but it’s a pity that today, almost all of the required materials-high-end bearing steel rely on imports.

China does not lack steel production, but the top Steel cannot be easily smelted. There are many parts in the mechanical structure that need to face severe wear, and even the bearings of some electric motors need to run forever during their life. It is impossible for ordinary steel to complete such a mission. At present, domestic steel mills only have high output, and there is no super high-quality steel that can be mass-produced.

One of the steel quality standards in the industry is the oxygen content in steel. 'PPM' is used in steelmaking. Middle is the unit of oxygen content, which means parts per million or parts per million. Generally speaking, in the steel industry, 8 PPM steel belongs to good steel; 5 PPM steel belongs to top steel, which is high-end bearing What you need. The research and development, manufacturing and sales of high-end bearing steel are basically monopolized by the world's bearing giants Timken of the United States and SKF of Sweden. In the past few years, they established bases in Yantai, Shandong and Jinan to purchase low-end materials from China. , Use their core technology to make high-end bearings and sell them to the Chinese market at ten times the price.

In order to make up for this regret, domestic researchers have also made long-term efforts. In order to solve this problem, researchers in Beijing We cut through the whole piece of steel, and improved the toughness of steel by adding rare earths in the production process of steel. They took the first step to produce good domestic steel.

Rare earths are called 'industrial vitamins.' Rare earth steel refers to steel containing a certain amount of rare earth. In the 1980s, China set off a climax in the development and application of rare earth steel. Scientists generally believe that adding rare earth in the steelmaking process is the technical direction for solving high-end bearing steel, but After adding rare earths to steel, the performance of steel becomes good and bad, and it is easy to block the gate during large-scale production. Although the technical bottleneck has not been broken through many years of research and development, this has also led to the application of rare earths in the iron and steel industry. From heat to cold.

The addition of rare earths in the steelmaking process can make the original high-quality steel more 'strong'. But how to add it is the core secret of the world's bearing giants. It is like dripping into the same basin of water. A drop of ink, 1 ton of steel plus How much rare earth is appropriate? How to add it?

The problem remains unsolved, and the consequence is: At present, with the exception of a small number of steel grades, iron and steel companies have almost given up the application of rare earths in actual production.

However, the road to the development of high-end bearing steel is not all bad news.

The Institute of Metal Research of the Chinese Academy of Sciences has made breakthroughs in the purification technology of rare earth steels.

In the previous stage, the material processing simulation research team of the Institute of Metals of the Chinese Academy of Sciences conducted physical anatomy and calculations of single-weight 100-ton large steel ingots and found that impurities were the cause The main source of uneven composition, based on this, proposed a new mechanism for the formation of defects in steel, which caused great repercussions in the industry and quickly obtained applications. Since then, the team has developed the purification preparation technology of commercial rare earth alloys and the special addition technology of rare earths in steel, thereby breaking through the technical bottleneck of the industrial application of rare earths in steel, and realizing the smooth and smooth process of adding rare earths to steel. Stable performance.

Recently, relevant national ministries and commissions are preparing relevant policies to promote the localization of high-end bearing steel. It can be said that to solve the 'stuck neck' problem of high-end bearing steel, we have taken another step forward.