Texture of surface layers obtained by ion nitriding of titanium alloys

Titanium metal and some of its alloys of the type Ti-Al-Me (Me=transition metal) were submitted to plasma nitriding. The resulting compound layer was examined by optical microscopy and by XR diffraction in order to establish both its microstructure and texture degree under different nitriding conditions. To this aim a texture evaluation method was employed, which was formerly devised and applied on surface layers obtained by boriding of steels. In these nitrided layers the Ti2N nitride was clearly textured while the TiN did not show an appreciable degree of preferred orientation of crystals. The influence of process conditions and alloy composition on the compound layer texture is discussed.