Alloy T-800 Cobalt-based Alloy Material Properties 

Material

COBALT ALLOY T-800

Chemical composition

Cr: 16.5～18.5%; Ni+Fe: ≤3.0%; Mo: 27.5～31.5%; C: ≤0.5%; N: ≤0.07%; Si: ≤3.5%; P: ≤0.03%; S: ≤0.03%; Co: remainder

Material properties

Tensile strength σb: 1793 MPa, elastic modulus σs: 2412 MPa, fracture toughness: 115 MPa·m^1/2, hardness HRC: 54～62, density: ≥8.2g/cm3.

Main characteristics

T800 is one of the commonly used cobalt-based alloys. Its biggest feature is the low friction coefficient, and it has excellent wear resistance, corrosion resistance and high temperature resistance.

T 800 cobalt-based alloys are composed of hard intermetallic compound (Laves) phases dispersed in a softer eutectic or solid solution matrix. They exhibit excellent wear and seizure resistance, high corrosion resistance and are particularly suitable for difficult lubrication situations. The wear resistance of Tribaloy alloys depends largely on the volume percentage of the Laves phase.

Tribaloy T-800 is designed to resist high temperature wear and abrasion. Due to its high chromium content, it has excellent oxidation and corrosion resistance. T-800 is harder and has better wear resistance than T-400.

T-800 exhibits excellent corrosion resistance in acetic acid (50% concentration, boiling) and phosphoric acid (85% concentration, 66°C). Excellent corrosion resistance is also observed in sulfuric acid (5% concentration, 66°C).

Applications

T-800 is widely used in the aerospace industry due to its high temperature wear and galling resistance, especially in hardfacing of aircraft engine turbine blades. In addition, it is also used to manufacture or coat various parts in high wear and corrosion environments, such as bearings, cams, retaining rings, diesel piston rings, mechanical seals, bearing seats, valve trims and pump components.