Bearing element for a bearing unit, and bearing unit with an increased life
A bearing element of a bearing unit includes a substrate, a first coating on the substrate and a second coating on the first coating. The first coating is configured to increase a wear resistance of the substrate and includes a first solid lubricant, and the second coating is softer than the first coating and includes a second solid lubricant. The solid lubricants of the first and second coatings may be MoS 2 , and the first coating may include between 3 and 30 at % Ti.
1 . A bearing element of a bearing unit, comprising:
a substrate,
a first coating on the substrate, the first coating being configured to increase a wear resistance of the substrate and comprising a first solid lubricant, and
a second coating on the first coating, the second coating being softer than the first coating and comprising a second solid lubricant,
wherein the first solid lubricant and the second solid lubricant each comprise MoS 2 .
2 . The bearing element according to claim 1 ,
wherein the first coating comprises Ti.
3 . The bearing element claim 2 ,
wherein the first coating has a hardness between 750 and 2500 HV.
4 . The bearing element according to claim 3 ,
wherein the first coating has a thickness between 0.2 and 4 micron.
5 . The bearing element according to claim 3 ,
wherein the second coating further comprises an adhesive or a binder.
6 . The bearing element according to claim 5 ,
wherein a hardness of the second coating is less than 150 HV.
7 . The bearing element according to claim 6 ,
including a bonding layer between the substrate and the first coating.
8 . The bearing element according to claim 3 ,
wherein the second coating further comprises an epoxy.
9 . A bearing unit comprising at least one bearing element according to claim 1 ,
wherein the bearing element is a ring, a rolling element, a cage, a separator, or a spacer.
10 . The bearing element according to claim 1 ,
wherein the first coating comprises MoS 2 and Ti and has a hardness between 750 and 2500 HV, and
wherein the second coating comprises MoS 2 and has a hardness of less than 150 HV.
11 . The bearing element according to claim 10 ,
wherein the second coating consists essentially of MoS 2 and an epoxy.
12 . The bearing element according to claim 1 ,
wherein the first coating consists essentially of MoS 2 and Ti and has a hardness between 750 and 2500 HV, and
wherein the second coating consists essentially of MoS 2 and has a hardness of less than 150 HV.
13 . The bearing element according to claim 12 ,
including a bonding layer between the substrate and the first coating.
14 . The bearing element according to claim 12 ,
wherein the first coating is formed of a plurality of alternating first layers consisting essentially of titanium and second layers consisting essentially of MoS 2 .
15 . The bearing element according to claim 1 ,
wherein the substrate comprises PEEK or PA6.6.
16 . The bearing element according to claim 1 ,
wherein the substrate comprises a ceramic material.
17 . The bearing element according to claim 1 ,
wherein the substrate comprises a bearing steel.