The hottest high-end bearing steel is difficult to

High end bearing steel is difficult to supplement the short board of China's manufacturing industry

"high end bearings rely on imports, why can't we make them ourselves?" After investigating five or six provinces including the three northeastern provinces, Zhejiang and Shandong, Wang Dongsheng, executive deputy director of the Shandong technology transformation center of the Chinese Academy of Sciences, found the answer: the bigger problem lies in the material, "without good steel, high-end bearings can never be made"

as an indispensable core component in mechanical equipment, bearings support mechanical rotating bodies, reduce their friction coefficient and ensure their rotation accuracy. In his opinion, if he doesn't need to use it, no matter planes, cars, high-speed railways, high-precision machine tools, instruments and meters, "all rotating parts need bearings"

it is no exaggeration to say that the bearing in the engine has been working in "Purgatory" - it not only has to run at a high speed for a long time at a speed of tens of thousands of revolutions per minute, but also bears various forms of stress extrusion, friction and ultra-high temperature. This puts forward high requirements for the accuracy, performance, service life and reliability of the bearing, and the key factor determining these four points lies in its material

unfortunately, although China's shaft manufacturing technology has been close to the world's top level, the material, that is, high-end bearing steel, almost all rely on imports

interviewed a large state-owned iron and Steel Group in East China and learned about the embarrassment of the latter. As one of the "top 100 Chinese enterprises", this iron and Steel Group has its own high-quality steel base, but it can't produce high-end steel for bearings and can only rely on imports. Not long ago, it spent nearly 100million yuan to import bearing steel

"ppm" is the unit of oxygen content in steelmaking, which means parts per million or parts per million. Experts from the Institute of metals of the Chinese Academy of Sciences told Science and technology that generally speaking, in the steel industry, 8 ppm steel is good steel; The steel of 5 ppm is the top steel, which is exactly what high-end bearings need. The R & D, manufacturing and sales of high-end bearing steel are basically monopolized by world bearing giants Timken of the United States and SKF of Sweden. A few years ago, they established bases in Yantai and Jinan, Shandong Province, respectively, 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

the addition of rare earth in the steelmaking process can make the original high-quality steel more "strong". But how to add, this is the core secret of the world's bearing giants

by 2020

rare earth is called "industrial vitamin", and rare earth steel refers to steel containing a certain amount of rare earth. In the 1980s, China set off a climax of R & D and application of rare earth steel. Scientists generally believe that adding rare earth in the steel-making process is the technical direction to solve the problem of high-end bearing steel. However, after adding rare earth into the steel, the performance of the steel becomes good and bad, and it is also very easy to block the gate in the process of mass production. Although it has been tackling key problems for many years, it still fails to break through the technical bottleneck, which also leads to the application of rare earth in the steel industry from hot to cold

just like a drop of ink in a basin of water, how many trace rare earths are suitable for 1 ton of steel? How

the problem remains unsolved, resulting in the following consequences: at present, except for a small number of steel grades, iron and steel enterprises almost give up the application of rare earth in actual production

however, on the road of developing high-end bearing steel, it is not all bad news

in the previous stage, the material processing simulation research team of the Institute of metals of the Chinese Academy of Sciences found that impurities were the main source of uneven composition through the physical anatomy and calculation of large steel ingots with a single weight of 100 tons. Based on this, a new defect formation mechanism in steel was proposed, which caused great repercussions in the industry and was quickly applied. Since then, the team has developed the purification preparation technology of commercial rare earth alloys and the special addition technology of rare earth in steel, thus breaking through the technical bottleneck of the industrial application of rare earth in steel. The oil 1 with impurity pollution must be replaced in time, realizing the smooth process and stable performance after adding rare earth in steel

it is learned that recently, in the aluminum profile manufacturing industry, relevant national ministries and commissions are brewing relevant policies to promote the localization process of high-end bearing steel. It can be said that we have taken another step forward to solve the problem of "neck sticking" of high-end bearing steel