Page 154 - The Tribology Handbook

A27 Bearing surface treatments and coatings

Table 27.5 The coating of sulfaces (continued)

Process Mechanism Surf... effects Design aspects
High velocity explosive coating The coating spray is driven by Coatings of CrC, WC and Produces very tough abrasion
successive explosive cobalt-based cermets about resistant coatings
hydrocarbon combustion 0.1 pm thick
cycles. This gives coatings
with very low porosity and
good adhesion
Thermochemically formed Ceramic coatings sprayed on Coatings such as chromium Produces a corrosion and
coatings and then heat treated at oxide of llOOHv about 0.1 abrasion resistant coating
temperatures of about 500°C mm thick
Laser cladding and alloying The application of coatings About 0.1 mm thick as a Good local corrosion and
derived from powders in maximum abrasion resistance
small controlled areas
Weld coatings Layers of hard material Thick layers up to 30 mm A relatively adaptable manual
applied from welding rods thick can be applied process suitable for the
and wires by gas or electric selectively repair and improved wear
welding resistance of heavy duty
components subject to
abrasive wear
Cladding Hard surface materials Thick wear-resistant materials Components, chutes, etc.,
attached to components by can be attached to surfaces requiring abrasion resistance
welding, adhesives, or roll
bonding

A27.5