Abstract: A composition and method for the manufacture of products of a precipitation hardenable martensitic stainless steel, the composition of which comprises at least 0.5% by weight of Cr and at least 0.5% by weight of Mo wherein the sum of Cr, Ni and Fe exceeds 50%. The method steps include smelting the material into a casting, hot extrusion followed by a number of cold deforming steps so as to obtain at least 50% martensite and finally an ageing treatment at 425-525° C. to obtain precipitation of quasicrystalline particles. Such material can be used in vehicle components where demands for corrosion resistance, high strength and good toughness are to be satisfied.

Abstract: The invention relates to a method and arrangement for preventing the passage of preferably an unmanned mining vehicle. The invention is based on the idea of providing a mining vehicle, such as a loading vehicle, with a mast (7) arranged on its upper outer structure and extending above other portions of the vehicle. In connection with the mast there is provided an emergency stop switch. Furthermore, at the upper portion of a mine gallery, or a similar operating site, is provided a barrier boom reachable to the mast for bordering the accepted travel area of the mining vehicle. If the mining vehicle tries to leave the accepted area, the mast hits the barrier boom and thus triggers the switch arranged in connection with the mast, thereby causing the mining vehicle to stop.

Abstract: The present invention relates to a coated cemented carbide insert with a binder phase enriched surface zone. The WC-grains have an average grain size in the range 1.0-3.5 &mgr;m, preferably 1.3-3.0 &mgr;m and the number of WC-grains larger than 2 times the average grain size is less than 10 grains/cm2 measured on a representative polished section 0.5 cm2 large, preferably less than 5 grains/cm2, and the number larger than 3 times the average grain size is less than 5 grains/cm2, preferably less than 3 grains/cm2. The cemented carbide is made by powder metallurgical methods and is in particular characterized in that the cooling rate, CR, from the sintering temperature, ST, exhibits the relationship 10<CR·(ST-1300)/1000<17.

Abstract: The present invention relates to cemented carbide tools for coldforming and drawing operations. The cemented carbide comprises WC with an average grain of <1 &mgr;m and 0.5-4 weight-% binder phase consisting of Co and Ni, <0.5 wt-% Mo, and <1 wt-% grain growth inhibitors V and/or Cr. The weight ratio Co:(Co+Ni) is 0.25-0.75 and the structure contains 1-5 vol-% of finely distributed eta phase with a size <5 &mgr;m.

Abstract: A process is provided for forming a material comprising an M3X1Z2 phase comprising the steps of: (a) providing a mixture of (i) at least one transition metal species, (ii) at least one co-metal species selected from the group consisting of aluminum species, germanium species and silicon species, and (iii) at least one non-metal species selected from the group consisting of boron species, carbon species and nitrogen species; (b) heating said mixture to a temperature of about 1000° C. to about 1800° C., in an atmosphere within a substantially enclosed heating zone, for a time sufficient to form said M3X1Z2 phase; wherein the atmosphere has an O2 partial pressure of no greater than about 1×10−6 atm. The process provides a substantially single phase material comprising very little MZx-phase.

Abstract: A down-the-hole percussive hammer includes a cylindrical casing adapted to carry a drill bit, and a piston mounted in the casing for reciprocal movement to repeatedly strike the drill bit. A top sub is mounted at a rear portion of the casing, the top sub including a front face facing the piston. A feed tube is mounted to the top sub and extends forwardly along a center axis of the casing and defines an air-conducting passage. The piston includes an axial through-hole which slidably receives the feed tube. The front face and the feed tube together define a recess opening toward the piston. A removable volume-changer is insertable into the recess to vary a volume of a space in which the piston slides, and thus control a pressure at which the piston operates.

Abstract: The present invention relates to a process for producing a coated cutting tool consisting of a coating and a substrate, wherein at least one refractory layer consisting of fine-grained, crystalline &ggr;-Al2O3 is deposited by reactive magnetron sputtering onto the moving substrate in a vacuum by pulsed magnetron sputtering in a mixture of a rare gas and a reactive gas at a pulse frequency set for 10 to 100 kHz. The deposition occurs with a rate of at least 1 nm/s with reference to a stationarily arranged substrate at a magnetron target power density in time average set for at least 10 W/cm2. The substrate temperature is in the range 400 to 700° C. and the flux of impinging particles onto each individual substrate is cyclically interrupted.

Abstract: A duplex ferritic-austenitic stainless steel alloy provided for seawater applications includes, in weight %: C maximum 0.05; Si maximum 0.8; Mn 0.03-4; Cr 28-35; Ni 3-10%, Mo 1.0-4.0; N 0.2-0.6; Cu maximum 1.0; W maximum 2.0; S maximum 0.010; Ce maximum 0.2; and the balance Fe together with normally occurring impurities and additives, wherein the ferritic content is 30-70 volume %, the alloy composition has a PRE-value higher than 42, and the PRE-value is at least 40 in both the ferritic and austenitic phases. A method is also provided which includes: providing a duplex ferritic-austenitic stainless steel alloy with the above-noted composition, forming a component with the alloy, and contacting the component with seawater. In preferred embodiments, the component comprises at least one of tubes, bars, heavy castings, forging, plates, wire or strip.

Abstract: According to the present invention there is now provided a body of cemented carbide provided with at least one wear resistant layer, which body contains a zone in the cemented carbide and adjacent to the applied layer, containing triangular WC platelets with a specific orientation. Different binder phase gradients are possible. The body is in particular suited for application of CVD diamond layers.

Abstract: The present invention describes a coated substrate material. The coating is formed by one or more layers of refractory compounds of which at least one layer of fine-grained, crystalline &ggr;-phase alumina, Al2O3, with a grainsize less than 0.1 &mgr;m. The Al2O3layer is deposited with a bipolar pulsed DMS technique (Dual Magnetron Sputtering) at substrate temperatures in the range 450° C. to 700° C., preferably 550° C. to 650° C., depending on the particular substrate material. Identification of the &ggr;-phase alumina is made by X-ray diffraction. Reflexes from the (400) and (440) planes occurring at the 2&thgr;-angles 45.8 and 66.8 degrees when using CuK&agr; radiation identify the &ggr;-phase Al2O3. The alumina layer is also very strongly textured in the [440]-direction. The Al2O3 layer is virtually free of cracks and halogen impurities. Furthermore, the Al2O3 layer gives the cutting edge of the tool an extremely smooth surface finish.

Abstract: There is now provided a cemented carbide grade for rock excavation purposes with 88-96 weight % WC, preferably 91-95% weight % WC, with a binder phase consisting of only cobalt or cobalt and nickel, with a maximum of 25% of the binder being Ni, possibly with small additions of rare earth metals, such as Ce and Y, up to a maximum of 2% of the total cemented carbide. The WC grains are rounded because of the process of coating the WC with cobalt, and not recrystallized or showing grain growth or very sharp cornered grains like conventionally milled WC, thus giving the bodies surprisingly high thermal conductivity. The average grain size should be from 8-30 &mgr;m, preferably from 12-20 &mgr;m. The maximum grain size does not exceed 2 times the average value and no more than 2% of the grains found in the structure are less than half of the average grain size.

Abstract: A surface-modified material and its associated method have been developed for surface modification of high temperature resistance alloys, such as FeCrAl alloys, in order to increase their oxidation resistance. The surface of the alloy is modified by treating it with a fluid, such as water-based colloidal silica dispersion. By this surface modification, the useful life of thin parts, such as wire and foil, has been significantly increased.

Abstract: The present invention relates to a method of making ultrafine WC—Co alloys from a well dispersed mixture of fine and non-agglomerated WC and Co powders, wherein the Co powders have a narrow grain size distribution wherein at least 80% of the grains have sizes in the interval x+0.2x with the interval of variation of 0.4x is not smaller than 0.1 um, and a carbon content of approximately the amount necessary to provide eta phase formation.

Abstract: A coated milling insert particularly useful for milling in low and medium alloyed steels with or without abrasive surface zones during dry or wet conditions at high cutting speed, and milling hardened steels at high cutting speed. The insert is characterized by a WC-Co cemented carbide with a low content of cubic carbides and a highly W-alloyed binder phase and a coating including an innermost layer of TiCxNyOz with columnar grains and a top layer of TiN and an inner layer of &kgr;-Al2O3.

Abstract: A percussive drilling component includes a cylindrical male screw thread formed of a steel material. The thread includes thread crests and thread roots interconnected by thread flanks. To protect the thread against corrosion, the thread is coated with a material having a lower electrode potential than the steel material. The coating is situated at least in regions located radially inwardly of the thread flanks. The male screw thread can be attached to a female screw thread of another percussive drilling component, the female screw thread also being coated with the material.

Abstract: A cutting insert is clamped in a pocket of a holder by a top clamp assembly which includes a clamp arm screwed to the holder, and a clamp plate interposed between the insert and a front part of the clamp arm. The clamp plate is formed of a harder and more wear-resistant material than the clamp arm and transmits clamping forces from the clamp arm to the cutting insert. The hard clamp plate shields the clamp arm from being impacted by chips generated during a machining operation, thereby minimizing wearing of the clamp arm.

Abstract: The present invention describes a coated CBN cutting tool for metal machining. The tool consists of one or more CBN substrate bodies with or without carbide backing. The coating is composed of one or more layers of refractory compounds of at least one layer of fine-grained, crystalline &ggr;-phase alumina (Al2O3) with a grainsize less than 0.1 &mgr;m. The Al2O3-layer is deposited with a bipolar pulsed DMS technique (Dual Magnetron Sputtering) at substrate temperatures in the range 450° C. to 700° C.

Abstract: The present invention describes a coated CBN cutting tool for metal machining. The tool is composed of one or more CBN bodies with or without a cemented carbide backing. The coating comprises one or more layers of refractory compounds of which at least one layer consists of fine-grained, crystalline &ggr;-phase alumina, Al2O3, with a grain give less than 0.1 &mgr;m. The &ggr;-phase alumina is deposited with a Plasma Activated Chemical Vapor Deposition (PACVD) process in which the plasma is produced by applying a bipolar pulsed DC voltage across two electrodes to which the tool substrates to be coated are fixtured and electrically connected.

Abstract: A tool extender and tool assembly is provided. The tool includes a shank extending from a working portion. The shank includes a bushing, a first guide portion, an externally threaded portion, and a second guide portion arranged successively in a direction away from the working portion. The tool extender includes a first end and a second end. The tool extender includes a substantially cylindrical bore in which the shank is receivable up to the bushing, the bushing abutting against a forward edge of the tool extender at the first end. The bore includes a first internal guide portion, an internally threaded portion for mating with the externally threaded portion, and a second internal guide portion arranged successively in a direction toward the second end of the tool extender.

Abstract: A holder for the detachable assembly of cutting tools includes a clamping mechanism, which has a piston axially movable by applying oil pressure on either of two opposite sides thereof. A projection of the piston includes a cone surface with a moderate cone angle arranged to co-operate with a wedge body which is self-locking in relation to the cone surface to keep the cutting tool clamped, even when oil pressure is relieved. In order to guarantee such self-locking, transverse grooves are provided in the cone surface enabling friction-reducing oil to be evacuated from the interface between the cone surface and an inner, partially cone-shaped surface on the wedge body.