Abstract: A process for adjusting the composition of a liquid metal, such as steel, is provided wherein liquid metal is sucked up from a start receptacle into a reactor which is at a reduced pressure with respect to the start receptacle. First, the liquid metal is made to flow inside the reactor under conditions close to plug flow where it undergoes a metallurgical treatment. Next, after the liquid metal has been conveyed through the reactor it is completely discharged into a finish receptacle which is also at a reduced pressure with respect to the reactor. To insure thorough mixing, the reactor is divided into a plurality of cells, each of which has its own independent gas injector for agitating the liquid metal therein.

Abstract: A process for the maceral analysis of a sample of crushed coal coated with resin includes the steps of scanning the surface of the sample with a microscope and measuring the reflectance of the vitrinite. The process further includes the steps of forming a digitized image having gray levels for each field of the microscope and eliminating those fields having a high resin content. In those fields which are not eliminated, the distribution of gray levels and gradients are determined, a binary image is formed by thresholding the gray gradients to determine zones of vitrinite, the distribution of the gray levels of the obtained zones of vitrinite are then determined and the reflectance of the vitrinite is calculated.

Abstract: An electrogalvanizing process, in which a strip is moved past an anode, plating solution is made to flow at a speed V with respect to the moving strip, and an electric current of current density J greater than 50 A/dm.sup.2 is passed between the strip and the anode, which comprises carrying out the deposition under conditions such that:J/J.sub.lim is less than or equal to 0.15;J.sup.2 /J.sub.lim is less than or equal to 22 A/dm.sup.2 ;where J.sub.lim is the limiting current density, corresponding to the current density plateau in the current versus potential curve characteristic of the plating solution flowing at the speed V in the vicinity of the strip. An electroplating cell of the radial type for implementing the process, in which cell the anode bed is continuous, is disclosed. The process facilitates the high-speed deposition of zinc which has low rugosity and is free of edge dendrites.

Abstract: Process for butt welding two metal blanks(1,2) of which the first blank is of steel and the second blank is of a metal having a melting temperature lower by more than 400.degree. C. than the melting temperature of the steel. The process includes positioning the two metal blanks (1,2) so that they contact each other in the region of their lateral faces to be butted together, maintaining the two metal blanks in contact, directing onto one of the principal faces of the metal blank (1) a high energy density bean (5) which passes through the first metal blank (1) and of which the focusing point is situated at a given distance from the joint plane (3) so as to generate in the region of the joint plane (3) a temperature equal to the melting temperature of the second metal blank (2) to within 10%, and displacing the high energy density beam (5).

Abstract: The subject of the invention is a hot-rolled steel sheet with high strength and high drawability, whose composition, expressed in percentages by weight, is:C.ltoreq.0.12%;0.5.ltoreq.Mn.ltoreq.1.5%;0.ltoreq.Si.ltoreq.0.3%;0.ltoreq.P.ltoreq.0.1%;0.ltoreq.S.ltoreq.0.05%;0.01.ltoreq.Al.ltoreq.0.1%;0.ltoreq.Cr.ltoreq.1%;0.01.ltoreq.Nb.ltoreq.0.1%;0.ltoreq.Ti.sub.eff .ltoreq.0.05%, Ti.sub.eff being the content of titanium not in the form of nitrides, sulfides or oxides; and whose structure comprises at least 75% of ferrite hardened by precipitation of niobium or niobium and titanium carbides or carbonitrides, the remainder of the structure comprising at least 10% of martensite and possibly bainite and residual austenite. The subject of the invention is also processes for manufacturing such sheets.

Abstract: According to the invention, the solution contains a water-soluble salt of heptanoic acid and an oxidizing agent and, preferably, a wetting agent.By virtue of the combination of these compounds, low concentrations are sufficient to obtain satisfactory corrosion protection, which makes it possible to maintain a nonfatty surface appearance (on the treated sheet) and facilitates the treatment of the solution effluent (or that of the subsequent degreasing effluent).

Abstract: An apparatus and method for manufacturing a reinforcement member wherein the reinforcement member includes a reelable steel tape being incorporated into concrete. The faces of the steel tape each include substantially rectalinear ribs arranged in at least one longitudinal row, the ribs being substantially parallel to each other and inclined with respect to the longitudinal direction of the tape. The ribs of one of the faces of the tape are symmetrical with respect to the ribs of the other of the faces of the tape in relation to the plane of the tape, parallel to the faces of the tape.

Abstract: A process for controlling the weldability of a sheet (1) of the composite metal sheet type having a layer (7) which is interposed between two metal facing sheets (3,5) and comprises a polymer (8) having a filler of conductive particles (9). This process comprises measuring by means of a signal of given frequency f applied to two electrodes (11,13) disposed in facing relation to each other, each electrode being in contact with a corresponding metal facing sheet (3,5), the voltage/current phaseshift .phi. due to the resistive and capacitive properties of the composite sheet (1). The response of the composite sheet (1) to this signal corresponds to that of an equivalent parallel RC circuit. Thereafter, the mass fraction of the conductive particles (9) is calculated from the value of .phi.. By comparing the determined mass fraction with prefixed thresholds, the weldability and the vibration-damping capacity of the composite sheet (1) are evaluated.

Abstract: A method and apparatus for identifying the position of an object that is movable in a determined three-dimensional zone by means of a video camera (20) or the like mounted on the movable object (14), the camera (20) being capable of being swivelled to sight targets (22) disposed around the movable object (14) and to enable the position and the orientation of said object to be determined accurately by triangulation. The invention is particularly applicable to accurately determining the position and the orientation of a sensor or a tool mounted on a robot.

Abstract: Process in which the said surface is pickled and then treated in two steps, a first treatment step of so-called "amorphous" phosphatization, suitable for depositing a coat of at least 0.2 g/m.sup.2, followed by a second treatment step called "nickel plating".In this way, it is possible to limit the amount of sludge at pickling while at the same time obtaining good adhesion of the enamel.In a complete sequence for manufacturing an article formed from direct-on enameled metal sheet, the sheet may be formed after pickling, especially after the first step called phosphatization and before the second step called nickel plating.

Abstract: The subject of the invention is a hot-rolled steel sheet with high strength and high drawability, whose composition, expressed in percentages by weight, is:C.ltoreq.0.12%;0.5.ltoreq.Mn.ltoreq.1.5%;0.ltoreq.Si.ltoreq.0.3%;0.ltoreq.P.ltoreq.0.1%;0.ltoreq.S.ltoreq.0.05%;0.01.ltoreq.Al.ltoreq.0.1%;0.ltoreq.Cr.ltoreq.1%;0.03.ltoreq.Ti.sub.eff .ltoreq.0.15%, Ti.sub.eff being the content of titanium not in the form of nitrides, sulfides or oxides;0.ltoreq.Nb.ltoreq.0.05%; and whose structure comprises at least 75% of ferrite hardened by precipitation of Ti or Ti and Nb carbides or carbonitrides, the remainder of the structure comprising at least 10% of martensite and possibly bainite and residual austenite. The subject of the invention is also processes for manufacturing such sheets.

Abstract: Device for guiding and feeding at least two sheet blanks previously brought edge to edge to form a joint plane, of the type including two units for supporting and feeding the sheet blanks in the direction of a high energy density beam disposed on each side of the joint plane and movable in synchronism with each other. Each supporting and feeding unit includes at least one lower series of carriages or at least one upper series of carriages, these carriages being articulated together in a vertical plane and movable in a direction parallel to the joint plane on a runway constituting a reference plane. Each carriage carries at least one shoe movable relative to the respective carriage in a direction perpendicular to the joint plane. The shoes of at least one of the two series of carriages cooperate with a device exerting a lateral pressure on the edges to be welded of the sheet blanks by a displacement of the shoes in a direction perpendicular to the joint plane.

Abstract: An oscillator supplies a signal of adjustable frequency to drive power ultrasonic actuators. The oscillator frequency is varied and the phase between the voltage and current of the signal is continuously measured. A computer determines the sign of the variation in the absolute value of the phase in the course of successive sampling cycles of predetermined duration and produces therefrom frequency correction signals for the oscillator. A frequency correction is applied to the oscillator in the same direction as the frequency correction applied previously if the variation in absolute value of the phase is negative, and in the opposite direction if the variation in absolute value of the phase is positive. If the variation in absolute value of the phase is zero, a frequency correction of random sign is applied to the oscillator.

Abstract: The invention relates to an exhaust muffler for a motor vehicle, consisting of an external casing (1), an internal casing (2) and a central part (3) consisting of perforated tubing (4) and transverse partitions (5) assembled together to form a chicane, called the insides. The central part (3) is made of an enameled steel, the steel having the following composition in thousandths of a percent by weight:carbon between 0 and 100manganese between 0 and 500phosphorus between 0 and 30sulfur between 0 and 40aluminum between 0 and 60titanium between 0 and 200copper between 0 and 60nitrogen between 0 and 15,the remainder being iron and residual impurities, said steel being obtained by hot rolling at a final rolling temperature exceeding the Ar.sub.3 point to obtain a strip, which is coiled at a temperature higher than 600 degrees Celsius and, after cold rolling, is subjected to a recrystallization annealing.

Abstract: Process for producing a strip of hot rolled steel sheet having a very high yield point of use in particular for the forming of parts and having a brittle/ductile transition at a temperature below -50.degree. C., characterized in that the steel having the following composition by weight;carbon.ltoreq.0.1%,1%.ltoreq.manganese.ltoreq.1.5%,silicon.ltoreq.0.3%,phosphorus.ltoreq.0.03%,sulphur.ltoreq.0.01%,0.01%.ltoreq.aluminium.ltoreq.0.1%,0.04%.ltoreq.niobium.ltoreq.0.06%,0.1%.ltoreq.titanium.ltoreq.0.15%,0.1%.ltoreq.molybdenum.ltoreq.0.2%,is subjected, after hot rolling, to a controlled cooling at a cooling rate of between 20.degree. C. per second and 100.degree. C. per second down to a temperature of between 550.degree. C. and 750.degree. C. of the end of the cooling. The invention also relates to the sheet obtained.

Abstract: A method of treating a metal layer present as a coating on a sheet metal substrate, wherein a powder is applied to said metal coating by propulsive means (e.g., spraying or the like) when said coating is at least partially in the liquid state. The powder is prepared by atomization in a manner adapted such that the powder is in the form of agglomerates having a mean diameter which is greater than the thickness of said liquid-state metal coating. With this use of this powder, it is easier to treat metal coatings in the liquid state, and the resulting treated coating is highly homogeneous, even if the atomized powder has a plurality of types of components.

Abstract: A steel strip and method for its production.

Abstract: The subject of the invention is a method of lubricating a mold (1) for the continuous casting of a metal product (16), of the type including a vigorously-cooled vertically-oscillating metal tubular element (2) defining a passage (4) for the cast metal and intended to cause, in contact with its wall (3) in said passage, the solidification of said metal product, in which a lubricant in the liquid state is injected through said metal tubular element toward said metal product being solidified, wherein said injection is carried out at points distributed annularly at a single level of said tubular element, said level lying at a distance greater than 20 cm from the lowest level at which solidification of said product is able to be initiated, and in that the flow rate of said lubricant is sufficient to cause a fraction of said lubricant to rise up along said wall to the level at which solidification of said product is effectively initiated.

Abstract: An aqueous solution useful for protecting steel from corrosion containing an alkaline aliphatic monocarboxylic acid salt having a linear chain of 6 to 12 carbon atoms, a triazole or diazole hydrocarbon and a non-ionic surfactant, the solution having a pH below 7. This aqueous solution is especially suited to the treatment of sheets at the outlet of an electrogalvanization line, particularly in a chloride medium.

Abstract: The invention relates to a flush-mountable cooktop having a steel support table covered on its two faces by a layer of an electrically insulating material, which table has openings in which burners are fixedly flush-mounted to the table by mounting elements which provide a seal. The burners each include a support layer of steel coated on its two faces with an electrically insulating material, and an electrically conducting layer having electrically conductive buses or the like for connecting the burner to an external source of electrical energy.