Effect of Ni content on high-temperature sliding wear properties of Cr₁₃Ni₅Si₂/γ alloy

The effects of Ni content on the microstructure and high-temperature wear resistance of Ni-base solid solution (γ) toughened Cr₁₃Ni₅Si₂ alloy were investigated. It is found that the average hardness of Cr₁₃Ni₅Si₂/γ alloy, the volume fraction of Cr₁₃Ni₅Si₂ primary dendrite and the individual hardness of Cr₁₃Ni₅Si₂ ternary metal silicide, all decreased with increasing the Ni content. The Cr₁₃Ni₅Si₂/γ alloys have excellent wear resistance under the test conditions of high-temperature sliding wear due to the high hardness of Cr₁₃Ni₅Si₂ and the good combination of toughness and strength of γ. The wear resistance of Cr₁₃Ni₅Si₂/γ alloy at 600°C increased considerably with increasing the Ni content. The wear of Cr₁₃Ni₅Si₂/γ alloy was governed by the slow process of micro-spalling or the pull-out of cracked Cr₁₃Ni₅Si₂ primary dendrites.