Abstract: A method for preparing a part in nickel-based superalloy is disclosed. The method comprises the following steps: elaborating a nickel-based superalloy with a composition capable of providing hardening by double precipitation of a gamma? phase and of a gamma? or delta phase; atomizing a melt of the superalloy in order to obtain a powder; sifting the powder; introducing the powder into a container; closing and applying vacuum to the container; densifiying the powder and the container in order to obtain an ingot or a billet; hot forming said ingot or said billet; wherein before the densification step, the powder and the container are heated for at least 4 hrs, at a temperature both above 1,140° C. and at least 10° C. less than the solidus temperature of the superalloy, and at a pressure causing densification of less than or equal to 15% of the powder volume.

Abstract: A method for preparing a part in nickel-based superalloy is disclosed. The method comprises the following steps: elaborating a nickel-based superalloy with a composition capable of providing hardening by double precipitation of a gamma? phase and of a gamma? or delta phase; atomizing a melt of the superalloy in order to obtain a powder; sifting the powder; introducing the powder into a container; closing and applying vacuum to the container; densifiying the powder and the container in order to obtain an ingot or a billet; hot forming said ingot or said billet; wherein before the densification step, the powder and the container are heated for at least 4 hrs, at a temperature both above 1,140° C. and at least 10° C. less than the solidus temperature of the superalloy, and at a pressure causing densification of less than or equal to 15% of the powder volume.

Abstract: The invention essentially relates to the use of a substantially nickel free non-stainless low alloy steel, for manufacturing at least the surface of an item intended to be put into contact with titanium or a titanium alloy, as well as to a method for manufacturing at least the surface of such an article. The invention notably relates the use of this alloy for manufacturing at least the contact surface of a mold for hot forming titanium-based alloys or titanium alloy in the solid-state, or for manufacturing at least the contact surface of tools for densifying and forming bulk titanium alloys or titanium or titanium alloy powders. Items intended to be put in contact with titanium or a titanium alloy may be produced with the invention.

Abstract: The device for the making a flat product (P) comprises a cylindrical wall, brought into rotation around a fixed core (1) and cooled by circulation of a fluid for the formation, of the flat product (P), onto an angular sector of the wall (2). The cooled wall on which is cast the metal is made up of a thin metal envelope forming a shell (2) simply inserted with possibility of sliding onto a circular surface (11) of the fixed core which constitute the central section of a fixed shaft (1) to hold and center the shell (2), the shaft (1) being connected with a thrust device allowing application of the shell (2) on the circular surface (11) of the shaft (1), the cooling fluid providing the lubrication of the bush thus made.

Abstract: The casting roll includes a hub (2) and a shell (3) which are arranged coaxially, and two flanges (5, 6) for supporting and radially centering the shell on the hub. Each flange includes a frustoconical part (51, 61) which cooperates with a corresponding frustoconical surface (34, 35) of the bore in the shell, the frustoconical surface being located in a region (A) where the internal diameter variations of the shell due to the expansion deformations are substantially zero.

Abstract: The subject of the invention is a nozzle for introducing liquid metal into a mold for the continuous casting of flat metal products, having two large walls and two side walls, of the type having at its lower end two outlet ports which are made in its lateral wall opposite each other and intended to send the liquid metal each toward a side wall of said mold, and at least two holes made in the bottom of said lower end, wherein a first group of said holes is arranged on one side of a longitudinal plane of symmetry of the nozzle, which plane includes the axes of the outlet ports, and a second group of said holes is arranged on the other side of said plane of symmetry.

Abstract: The solidification of the strip (9) is performed by introducing liquid metal between two horizontal rolls rotating in opposition directions (1, 1') which are cooled by an internal circulation of a coolant fluid. A casting space is defined between the rolls and their outer surfaces (3, 3') have a roughness. The casting space is blanketed by a cooling gas or a mixture of gases through a lid (10) covering the casting space. An adjustment of the crown or profile of the rolls (1, 1') is performed by modulating the quantity of cooling gas blown onto the rolls and/or the nature and composition of the gas at least in the vicinity of the surface of each roll (1, 1') upstream of its region of contact with the liquid metal (2).

Abstract: The subject of the invention is a process for conditioning the copper or copper-alloy external surface of an element of a mold for the continuous casting of metals, of the type including a step of nickel plating of said surface and a step of nickel removal therefrom, wherein:a preparation of said surface, comprising in succession an operation of cleaning said bare surface, an operation of pickling said bare surface in an oxidizing acid medium and an operation of brightening said bare surface, is carried out;then, an operation of nickel plating of said bare surface is carried out by electroplating, by placing said element as the cathode in an electrolyte consisting of an aqueous nickel sulfamate solution containing from 60 to 100 g/l of nickel;then, after said element has been used, an operation of partially or completely removing the nickel from said surface electrolytically is carried out, by placing said element as the anode in an electrolyte consisting of an aqueous nickel sulfamate solution containing fro

Abstract: The invention relates to a nozzle for introducing a liquid metal into a mold for continuous casting of metals, of the type comprising a tubular first part, one end of which is intended to be connected to a receptacle enclosing said liquid metal, and the other end of which opens into a hollow second part in which at least one portion of the internal space is oriented substantially perpendicularly to said tubular first part, said portion comprising at each of its ends at least one orifice intended to emerge into the casting space of said mold, which comprises an obstacle placed in the path of the liquid metal inside said tubular first part or in its extension, said obstacle consisting of at least one perforated component intended to divert the metal from its preferential trajectory inside the nozzle.

Abstract: A casting roll for continuous casting of metals. The roll comprising a core (2) and a sleeve (3), coaxially arranged one with respect to the other. The sleeve is axially coupled to the core by a inward projection (33) on the sleeve which abuts a shoulder (24) on the projection. The projection and the shoulder are located in a plane (P) substantially median with respect to the roll. The sleeve is radially centered on the core by flanges (5) and (6) which are elastically coupled together. The flanges and sleeve have relieved surfaces (37) which allow the sleeve to expand axially without bowing. The invention is particularly well suited for continuous casting thin metallic strips, especially steel strips, between two of these casting rolls.

Abstract: The invention is directed to the production of non-fragile shaped members from powders comprising spheroidal metal particles.For this purpose, the invention provides a process for the production of shaped parts from powders comprising spheroidal metal particles which are mixed with from 0.2% to 2% of lubricant, comprising the combination of the following successive steps, performed in the below-indicated order:(a) mixing the powder formed by spheroidal metal particles with an amount of water-soluble cellulose gum between 0.2% and 2%, and with an amount of water which is also between 0.2% and 2%;(b) a cold compacting operation;(c) an optional oven drying operation;(d) a two-phase sintering operation, in an atmosphere which is neutral or reducing with respect to the compacted powder, the first phase being effected at a temperature of from 300.degree. to 500.degree. C. and the second phase being effected at a temperature which is substantially higher and variable with the nature of the powder.