The metal floating seal ring is generally made of alloy cast iron metal mold precision casting or roller bearing steel after processing and heat treatment.

Wear resistance and corrosion resistance are the two main requirements of floating oil seals for metal seal rings. From the perspective of corrosion resistance, there is no significant difference between the alloy cast iron floating seal ring and the bearing steel floating seal ring under the same conditions.

The wear marks on the sealing surface of the bearing steel floating seal ring are relatively flat, but there are many fine grooves on the sealing surface of the alloy cast iron floating seal ring. Due to the relatively flat wear marks on the sealing surface of the bearing steel floating seal ring, under the action of axial pressure, there is no place for lubricating oil to store, which is easy to cause dry friction and wear quickly. However, the sealing surface of the alloy cast iron floating seal ring can form many fine grooves during the wear process to provide storage space for lubricating oil, so that the sealing surface of the alloy cast iron captive seal ring forms a combination of fluid lubrication, adsorption film lubrication and dry friction. The film lubrication method, due to the good lubrication, wears relatively slowly. Therefore, in terms of wear resistance, alloy cast iron floating seal rings are better than bearing steel floating seal rings.

The surface hardness of the sealing surface of the floating seal ring is relatively high, generally reaching above HRC58, and the highest can reach HRC72. In order to make metal materials achieve higher hardness and improve wear resistance, for most materials, floating seal rings also need to undergo overall quenching hardening treatment or surface hardening treatment on the sealing surface. Surface hardening treatment can minimize the thermal deformation of the metal ring.