Metal-to-metal spherical bearing
View Patent ↗A metal-to-metal bearing comprising a bearing housing of a first material and a ball of a second material held within the housing, the interface between the housing and the ball comprising two bearing surfaces, wherein one of the first and second materials is a titanium alloy having a diffusion zone near its surface to which is adhered a coating of titanium nitride to provide one of the bearing surfaces.
1. A metal-to-metal bearing comprising a bearing housing of a first material and a ball of a second material held within the housing, the interface between the housing and the ball comprising two bearing surfaces, wherein one of the first and second materials is a titanium alloy having a diffusion zone near its surface to which is adhered a coating to provide one of the bearing surfaces.
2. A bearing according to claim 1 , wherein the coating is titanium nitride.
3. A bearing according to claim 1 , wherein the other of the first and second materials is a copper alloy.
4. A bearing according to claim 1 , wherein the other of the first and second materials is titanium alloy having a coating of titanium nitride at the bearing surface.
5. A bearing according to claim 1 , wherein the coating is applied by a physical vapor deposition process.
6. A bearing according to claim 1 , wherein the diffusion zone is a nitride diffusion zone in the titanium alloy surface creating a hardened subsurface.
7. A bearing according to claim 1 , wherein the diffusion and physical vapor deposition processing is carried out under vacuum at 700° C. (1292°) Fahrenheit).