Effect of Si and Cr additions to carbon steel on material transfer in a steel/TiN coated tool sliding contact

A crossed cylinders sliding test, simulating the contact between the chip and the tool in machining, is used to evaluate material transfer and friction characteristics of a TiN coating against specifically designed model steels. These include one base reference, only alloyed with C (Base steel) and two alloyed also with 1mass% Si or Cr. When sliding against the Base steel, an Fe–O layer is formed on the coating. Against the Si and Cr alloyed steels, Fe–Si–O and Fe–Cr–O layers are formed. In these oxides, Si and Cr are enriched, i.e. preferentially transferred from the steels. Compared to the Base steel, the friction coefficient is significantly lower against the Si alloyed steel and higher against the Cr alloyed steel. •Material transfer and friction behavior were analyzed in steel/coated tool sliding.•Model steels allowed specific studies on influence from individual alloy elements.•Fe–Si–O and Fe–Cr–O layers formed on the coating slid against Si and Cr added steels.•Si and Cr were highly enriched in these oxide layers.•Si and Cr additions significantly influenced the friction coefficient.