A steel material for a torsionally stressed component, such as a driveshaft, having a minimum tensile strength of 800 MPs, and the microstructure consists of more than 50 vol. % of bainite, having an alloy with the following composition in wt. %: C: 0.02 to 0.3; Si: up to 0.7; Mn: 1.0 to 3.0; P: max. 0.02; S: max. 0.01; N: max. 0.01; Al: up to 0.1; Cu: up to 0.2; Cr: up to 3.0; Ni: up to 0.3; Mo: up to 0.5; Ti: up to 0.2; V: up to 0.2; Nb: up to 0.1; B: up to 0.01; where 0.02≤Nb+V+Ti≤0.25, residual iron, and smelting impurities. The steel material is inexpensive and has good torsional fatigue strength when used for a torsionally stressed component. The invention also relates to a method for producing a component made of the material and to such a component.

A method for converting wire rod of nonferrous metals and alloys thereof to wire with high elongation and in the annealed state, wherein the reduction in diameter in order to pass from wire rod to wire is carried out by way of a plastic deformation process. The temperature of the metal subjected to plastic deformation is controlled in order to have, at the end of the plastic deformation process, the wire at a temperature higher than or equal to the recrystallization temperature. This avoids the thermal treatment of annealing, necessary in conventional production techniques, achieving a considerable saving in production costs and a wire with characteristics similar to those of a wire subjected to annealing.

A lumen stent preform is provided using a plasma nitriding technology, a preparation method thereof, a method for preparing a lumen stent by using the preform, and a lumen stent obtained according to the method. The preform is manufactured by using pure iron or an iron alloy containing no strong nitrogen compound, has a hardness of 160-250HV0.05/10, and has a microstructure that is a deformed structure having a grain size number greater than or equal to 9 or a deformed structure after cold machining. Alternatively, the preform is an iron alloy containing a strong nitrogen compound, and has a microstructure that is a deformed structure having a grain size number greater than or equal to 9 or a deformed structure after cold machining. The lumen stent preform meets the requirements of a conventional stent for radial strength and plasticity, so that plasma nitriding is applicable to commercial preparation of a lumen stent.

A tungsten wire contains tungsten or a tungsten alloy. An average width of surface crystal grains in a direction perpendicular to an axis of the tungsten wire is at most 76 nm. The tungsten wire has a tensile of at least 4800 MPa, and a diameter of at most 100 μm.

A medical device and a method and process for at least partially forming a medical device, which medical device has improved physical properties. The one or more improved physical properties of the novel metal alloy can be achieved in the medical device without having to increase the bulk, volume and/or weight of the medical device.

A steel wire which has an excellent fatigue limit when made into a spring is provided. A chemical composition of the steel wire according to the present embodiment consists of, in mass %, C: 0.53 to 0.59%, Si: 2.51 to 2.90%, Mn: 0.70 to 0.85%, P: 0.020% or less, S: 0.020% or less, Cr 1.40 to 1.70%, Mo: 0.17 to 0.53%, V: 0.23 to 0.33%, Cu: 0.050% or less, Ni: 0.050% or less, Al: 0.0050% or less, Ti: 0.050% or less, N: 0.0070% or less, Ca: 0 to 0.0050%, and Nb: 0 to 0.020%, with the balance being Fe and impurities. In the steel wire, a number density of V-based precipitates having a maximum diameter ranging from 2 to 10 nm is 500 to 8000 pieces/μm.sup.2.

One aspect relates to a process for preparing a ring electrode including the steps of a) providing a monolithic metal precursor, wherein the monolithic metal precursor includes an outer tube forming a first cavity of the precursor, and wherein the outer tube has a wall including in one section an inner tube forming a second cavity of the precursor; b) preparing a composite precursor by inserting a first sacrificial core element into the first cavity of the precursor provided in a) and a second sacrificial core element into the second cavity of the precursor provided in a); c) forming the composite precursor obtained in b) to obtain a formed composite having a smaller outer diameter than the composite precursor obtained in b); d) separating a composite disk from the formed composite obtained in c); e) removing the first and the second sacrificial core element from the composite disk obtained in d).

According to the invention, the electrode wire (1) for electric discharge machining comprises a metal core (2), in one or more layers of metal or metal alloy. On the metal core (2), a coating (3) having an alloy different from that of the metal core (2) contains more than 50 wt % zinc. The coating (3) comprises copper-zinc alloy (3a) of fractured γ phase, and covers the majority of the metal core (2). The coating (3) contains covered pores (5a, 5b, 5c, 5d, 5e) larger than 2 μm.

The present disclosure relates to a bimetallic tube comprising a first metallic tube having an inner diameter and an outer diameter, and a second metallic tube having an inner diameter and an outer diameter, wherein the first metallic tube is arranged within and force-fitted to the second metallic tube and wherein the first metallic tube comprises a zirconium (Zr) based alloy and wherein the second metallic tube comprises an austenitic stainless steel. The present disclosure also relates to a method for manufacturing a bimetallic tube comprising the steps of providing a first metallic tube having an inner diameter and an outer diameter, providing a second metallic tube having an inner diameter and an outer diameter, wherein the outer diameter of the first metallic tube is smaller than the inner diameter of the second tube, insetting the first metallic tube into the second metallic tube, cold-drawing the first and second metallic tubes together, such that the first and second metallic tubes are force-fitted together.

The present disclosure relates to a bimetallic tube comprising a first metallic tube having an inner diameter and an outer diameter, and a second metallic tube having an inner diameter and an outer diameter, wherein the first metallic tube is arranged within and force-fitted to the second metallic tube and wherein the first metallic tube comprises a zirconium (Zr) based alloy and wherein the second metallic tube comprises an austenitic stainless steel. The present disclosure also relates to a method for manufacturing a bimetallic tube comprising the steps of providing a first metallic tube having an inner diameter and an outer diameter, providing a second metallic tube having an inner diameter and an outer diameter, wherein the outer diameter of the first metallic tube is smaller than the inner diameter of the second tube, insetting the first metallic tube into the second metallic tube, cold-drawing the first and second metallic tubes together, such that the first and second metallic tubes are force-fitted together.