Sliding member

A sliding member, comprising:

• a metallic base;
• at least one intermediate bonding layer composed of at least one metal and disposed on the metallic base;
• and
• a multilayer protective coating disposed on the intermediate bonding layer, the multilayer protective coating including a plurality of first layers and a plurality of second layers arranged in an alternating manner;
• the multilayer protective coating further including a plurality of periodicity layer groups each defined by a first layer of the plurality of first layers and an adjacent second layer of the plurality of second layers;
• wherein each of the plurality of first layers and each of the plurality of second layers are composed of Al-containing chromium nitride;
• wherein, in each periodicity layer group of the plurality of periodicity layer groups, a thickness ratio of the first layer to the second layer is from 1.5 to 5;
• wherein the plurality of first layers each include 27 to 32 atom-% of Al;
• wherein the plurality of second layers each include 18 to 20 atom-% of Al;
• wherein the multilayer protective coating has a total Al content of 15 to 40 atom-%;
• and
• wherein a total thickness of the at least one intermediate bonding layer and the multilayer protective coating is from 10 μm to 50 μm.

A sliding member, comprising:

• a metallic base;
• at least one intermediate bonding layer disposed on the metallic base, the at least one intermediate bonding layer composed of at least one metal;
• and
• a multilayer protective coating disposed on the intermediate bonding layer, the multilayer protective coating including a plurality of first layers and a plurality of second layers arranged in an alternating manner;
• the multilayer protective coating further including a plurality of periodicity layer groups each defined by a first layer of the plurality of first layers and an adjacent second layer of the plurality of second layers;
• wherein each of the plurality of first layers and each of the plurality of second layers are composed of Al-containing chromium nitride;
• wherein, in at least one periodicity layer group of the plurality of periodicity layer groups, i) the first layer has a higher Al content than the second layer and ii) a thickness ratio of the first layer to the second layer is from 1.5 to 5;
• wherein the multilayer protective coating has a total Al content of 15 to 40 atom-%;
• and
• wherein:
• a total thickness of the at least one intermediate bonding layer and the multilayer protective coating is from 6 μm to 70 μm;
• a hardness of the multilayer protective coating is from 1600 to 2600 HV;
• and/or
• the multilayer protective coating has a porosity lower than 6%.