Abstract: An uncoated titanium-based carbonitride cutting tool insert with superior plastic deformation resistance and wear resistance is provided. This is accomplished by heat treating the material in nitrogen atmosphere under conditions to obtain a nitrogen rich surface zone, also containing substantial amounts of binder phase.

Abstract: The present invention relates to a cutting tool insert of a carbonitride alloy with titanium as the main component and containing tungsten and cobalt useful for machining, e.g., turning, milling and drilling of metal and alloys. The insert is provided with a coating of at least one wear resistant layer. The composition of the insert and the coating is chosen in such a way that a crack-free coating in a moderate (up to 1000 MPa) compressive residual stress state is obtained. The absence of cooling cracks in the coating, in combination with the moderate compressive stress, gives the tool insert improved properties compared to prior art tools in many cutting tool applications.

Abstract: The present invention relates to a sintered body of titanium-based carbonitride alloy comprising hard constituents containing at least tungsten in addition to titanium in a binder phase based on cobalt. There are four distinctly different microstructural components, namely: A) cores which are remnants of and have a metal composition determined by the raw material powder; B) tungsten-rich cores formed during the sintering; C) outer rims with intermediate tungsten content formed during the sintering; and D) a binder phase of a solid solution of at least titanium and tungsten in cobalt. Toughness and wear resistance are varied by adding WC, (Ti,W)C, and/or (Ti,W)(C,N) in varying amounts as raw materials.

Abstract: There is disclosed a method for edge rounding of cutting tool inserts, in combination with a high surface finish over the whole insert, of cemented carbide or titanium-based carbonitride alloys. An electrolytic method is used with an electrolyte which provides an even removal of both binder phase and hard constituent phases. The electrolyte comprises perchloric (HClO.sub.4) or sulphuric (H.sub.2 SO.sub.4) acid, in amounts >15 and <50 volume %, in methanol or other suitable organic liquid. The method is easier to control than conventional mechanical methods and is particularly useful for providing very small edge radii of about 10 .mu.m in combination with a high surface finish over the whole insert which cannot be made by mechanical or other electrolytic methods.

Abstract: A titanium-based carbonitride cutting tool insert with superior thermal shock resistance is disclosed. This is accomplished by sintering the material under conditions where the melting process is reversed. The melt forms in the center of the material first and the melting front propagates outwards towards the surface. This leads to minimal porosity and a macroscopic cobalt depletion towards the surface. The cobalt depletion, in turn, leads to a favorable compressive residual stress in the surface zone.

Abstract: The present invention relates to a method for polishing coated cutting tools and wear parts, where at least the outer layer of the coating consists of TiN, TiC or Ti(C,N), to a high surface finish. An electrolytic method is used with an electrolyte consisting of perchloric (HClO.sub.4) or sulphuric (H.sub.2 SO.sub.4) acid, 2-50 volume %, in methanol or other organic liquid. The method is easier to control than conventional mechanical methods and renders a high surface finish over the whole coated part.

Abstract: There is disclosed a method for edge rounding of cutting tool inserts of cemented carbide or titanium based carbonitride alloys. An electrolytic method is used with an electrolyte which provides an even removal of both binder phase and hard constituent phases. The electrolyte comprises perchloric (HC10.sub.4) sulphuric (H.sub.2 SO.sub.4) acid, 2-15 vol %, and mixtures thereof in methanol or other suitable organic liquid. The method is easier to control than conventional mechanical methods and is particularly useful for providing very small edge radii of about 10 .mu.m which cannot be made by mechanical methods.