Performance comparison of four bearing materials: ordinary bearing steel AISI52100 (GCr15), stainless steel AISI440 (9Cr18), silicon nitride (Si3N4) and zirconia (ZrO2). Ceramic bearing is an important mechanical base. Because it has metal bearings Incomparable excellent performance, high temperature resistance, super strength, etc. are the first in the world of new materials. In the past ten years, it has been used more and more widely in various fields of national economy and people's livelihood. First, because ceramics are scarcely resistant to corrosion, ceramic rolling bearings are suitable for operation in harsh conditions covered with corrosive media.
Secondly, because the density of ceramic rolling balls is lower than that of steel, and the weight is much lighter, the centrifugal effect of the outer ring during rotation can be reduced by 40%, and the service life is greatly extended.
Third, ceramics are less affected by thermal expansion and contraction than steel, so when the bearing clearance is constant, the bearing can be allowed to work in an environment where the temperature difference changes drastically.
Fourth, because the elastic modulus of ceramics is higher than that of steel, it is not easy to deform when subjected to force, so it is conducive to increasing the working speed and achieving higher accuracy. Ceramic bearings have the characteristics of high temperature resistance, cold resistance, wear resistance, corrosion resistance, magnetic and electrical insulation, oil-free self-lubrication, and high speed. It can be used in extremely harsh environments and special working conditions. It can be widely used in aviation, aerospace, marine, petroleum, chemical, automotive, electronic equipment, metallurgy, electric power, textiles, pumps, medical equipment, scientific research and defense and military fields. High-tech products using new materials.
The ceramic bearing rings and rolling elements are made of all-ceramic materials, including zirconia (ZrO2), silicon nitride (Si3N4), and silicon carbide (Sic). The holder is made of polytetrafluoroethylene, nylon 66, polyetherimide, zirconia, silicon nitride, stainless steel or special aviation aluminum, thereby expanding the application area of ceramic bearings.
Medical equipment, cryogenic engineering, optical instruments, high-speed machine tools, high-speed motors, printing machinery, food processing machinery.
In the fields of aerospace, navigation, nuclear industry, petroleum, chemical industry, light textile industry, machinery, metallurgy, electric power, food, locomotive, subway, high-speed machine tools and scientific research and defense military technology, it needs to be at high temperature, high speed, deep cold, flammable, Explosive, strong corrosion, vacuum, electrical insulation, non-magnetic, dry friction and other special working conditions, the indispensable role of ceramic bearings is gradually being recognized.
With the continuous progress of processing technology and the increasing level of technology, the cost of ceramic bearings has continued to decline. It has been used in a small range of high, precision, and sharp areas from the past, and has gradually been extended to various industrial sectors of the national economy. Product market prices It is also gradually approaching practical use, reaching a level acceptable to users. The wave of large-scale application of ceramic bearings has surged!
Advantages and main applications of ceramic bearings
2020 03/30