Advanced chromium carbide-based hardfacings

Ceramic metal composite powders are widely used in thermal spray technologies; however, application of such hardphases in cladding systems has not been strongly developed yet. In the present study, two different hardfacings produced by the plasma transferred arc (PTA) process were analysed and compared to reveal differences between NiCrBSi coatings reinforced with standard chromium carbide and chromium-based cermet powders. The coatings were produced from a mixture of hardphases (Cr3C2 or Cr3C2–Ni) and nickel based powder with a ratio of 40/60 vol.%. The coatings' thickness was set to 2–2.5 mm on an austenite substrate. Hardfacings were characterised in terms of their microstructures, mechanical properties and impact–abrasion wear resistance at room and elevated temperatures. The manufactured Cr3C2–Ni reinforced hardfacing alloy has shown promising microstructural features with a low level of carbide dissolution and high temperature wear performance.

► Application of advanced cermets as reinforcement for Ni-based matrix hardfacings.
► Minimal hardphase dissolution during hardfacing process.
► Homogeneous distribution of primary hardphases in metal matrix.
► Increased impact/abrasion wear resistance of produced hardfacings.
► High temperature stability up to 700 °C with negligible wear rate growth.