Abstract: Steel for manufacturing cemented steel parts, characterized in that the composition thereof in weight percentages is: 0.1%?C?0.15%; 0.8%?Mn?2%; 1%?Cr?2.5%; 0.2%?Mo?0.6%; trace elements?Si?0.35%; trace elements?Ni?0.7% trace elements?B?0.005%; trace elements?Ti?0.1% trace elements?N?0.01% if 0.0005% (5 ppm)?B?0.005%, and trace elements?N?0.02% if trace elements?B?0.0005% (5 ppm); trace elements?Al?0.1%; trace elements?V?0.3%; trace elements?P?0.025%; trace elements?Cu?1%, preferably?0.6%; trace elements?S?0.1%; the remainder being iron and impurities resulting from production. A cemented steel part made with this steel, and to the method for manufacturing same.

Abstract: A mechanical steel part in steel with high characteristics, characterized in that its composition, comprising in weight percentages, is 0.05%?C?0.25%; 1.2%?Mn?2%; 1%?Cr?2.5%; wherein the contents of C, Mn and Cr are such that (830-270C %-90 Mn %-70Cr %)?560; 0<Si?1.55; 0<Ni?1%; 0<Mo?0.5%; 0<Cu?1%; 0<V?0.3%; 0<Al?0.1%; 0<B?0.005%; 0<Ti?0.03%; 0<Nb?0.06%; 0<S?0.1%; 0<Ca?0.006%; 0<Te?0.03%; 0<Se?0.05%; 0<Bi?0.05%; 0<Pb?0.1%; the remainder of the steel part being iron and impurities resulting from processing, and wherein the in that its structure of the steel is bainitic and contains no more than a total of 20% of martensite and/or pro-eutectoid ferrite and/or pearlite.

Abstract: A piston for an internal combustion engine is formed from a metal part cast in one piece. Heating of a billet is carried out so as to bring it to an intermediate temperature between its solidus temperature and its liquidus temperature, and shaping thereof by thixoforging is carried out.

Abstract: A spring steel with high fatigue resistance in air and in corrosive conditions and with high resistance to cyclic sag, having the composition in weight percent: C=0.45-0.70% Si=1.65-2.50% Mn=0.20-0.75% Cr=0.60-2% Ni=0.15-1% Mo=traces-1% V=0.003-0.8% Cu=0.10-1% Ti=0.020-0.2% Nb=traces-0.2% AI=0.002-0.050% P=traces-0.015% S=traces-0.015% O=traces-0.0020% N=0.0020-0.0110% the balance being iron, and impurities resulting from the steel making process, where the carbon equivalent Ceq content calculated according to the formula: Ceq %=[C %]+0.12 [Si %]+0.17 [Mn %]?0.1 [Ni %]+0.13 [Cr %]?0.24 [V %] is between 0.80 and 1.00%, and whose hardness, after quenching and tempering, is greater than or equal to 55 HRC.

Abstract: The invention provides a method of fabricating a steel part, the method comprising the steps of: preparing and casting a steel having the following composition in percentage by weight: 0.06%?C?0.25%; 0.5%?Mn?2%; traces?Si?3%; traces?Ni?4.5%; traces?Al?3%; traces?Cr?1.2%; traces?Mo?0.30%; traces?V?2%; traces?Cu?3.5%; and satisfying at least one of the following conditions: 0.5%?Cu?3.5%; 0.5%?V?2%: 2?Ni?4.5% and 1%?Al?2%; ?the remainder being iron and impurities resulting from preparation; hot deforming the cast steel at least once at a temperature in the range 1100° C. to 1300° C. in order to obtain a blank of the part; controlled cooling of the blank for the part in still air or forced air; and heating the steel to perform precipitation annealing before or after machining the part from said blank. The invention also provides a part obtained by the method.

Abstract: The invention relates to a steel for mechanical construction, wherein its composition in percentages by weight is: 0.35%?C?1.2%; 0.10%?Mn?2.0%; 0.10%?Si?3.0%; traces?Cr?4.5%; traces?Mo?2.0%; traces?Ni?4.5%; traces?V?0.5%; traces?Cu?3.5% with Cu?Ni %+0.6 Si % if Cu?0.5%; traces?P?0.200%, traces?Bi?0.200%, traces?Sn?0.150%, traces?As?0.100%, traces?Sb?0.150%, with 0.050%?P %+Bi %+Sn %+As %+Sb %?0.200%, traces?Al?0.060%; traces?Ca ?0.050%; traces?B?0.01%; traces?S?0.200%; traces?Te?0.020%; traces?Se?0.040%; traces?Pb?0.070%; traces?Nb?0.050%; traces?Ti?0.050%; the remainder being iron and impurities resulting from the manufacture.

Abstract: The invention relates to a steel for mechanical construction, wherein its composition in percentages by weight is: 0.35%?C?2.5%; 0.10%?Mn?2.5%; 0.60%?Si?3.0%; traces?Cr?4.5%; traces?Mo?2.0%; traces?Ni?4.5%; traces?V?0.5%; traces?Cu?4% with Cu?Ni %+0.6 Si % if Cu?0.5%; traces?Al?0.060%; traces?Ca?0.050%; traces?B?0.01%; traces?S?0.200%; traces?Te?0.020%; traces?Se?0.040%; traces?Pb?0.070%; traces?Nb?0.050%; traces?Ti?0.050%; the remainder being iron and impurities resulting from the manufacture. The invention also relates to a method of hot-shaping a steel part, wherein a billet of steel of the preceding composition is obtained, it is heated to a temperature between the solidus and the liquidus so as to obtain a liquid phase and a globular solid phase, shaping of the said billet is carried out by thixoforging so as to obtain the said part, and cooling of the said part is carried out. Finally, the invention relates to a steel part thus obtained.

Abstract: Steel for the manufacture of a component for bearings, the chemical composition of which comprises, by weight: 0.6%≦C≦1.5%; 0.4%≦Mn≦1.5%; 0.75%≦Si≦2.5%, 0.2%≦Cr≦2%; 0%≦Ni≦0.5%; 0%≦Mo≦0.2%; 0%≦Al≦0.05%; S≦0.04%; the balance being iron and impurities resulting from smelting and the composition furthermore satisfying the relationships: Mn≦0.75+0.55×Si and Mn≦2.5−0.8×Si. Process for the manufacture of a bearing component.

Abstract: Steel for the manufacture of a component for bearings, the chemical composition of which comprises, by weight: 0.6%≦C≦1.5%; 0.4%≦Mn≦1.5%; 0.75%≦Si≦2.5%; 0.2%≦Cr≦2%; 0%≦Ni≦0.5%; 0%≦Mo≦0.2%; 0%<Al≦0.05%; S≦0.04%; the balance being iron and impurities resulting from smelting and the composition furthermore satisfying the relationships: Mn≦0.75+0.55×Si and Mn≦2.5−0.8×Si. Process for the manufacture of a bearing component.

Abstract: A carbon or low-alloy steel is provided with improved machinability. The carbon content of the steel is less than 1.5% and the sum of the alloy elements contained therein is less than 9%. The steel contains oxide and sulfide inclusions, and the chemical composition of the steel includes 0.1%≦Mn, 0.01%≦Al≦0.05%, 0.025%≦S≦0.3%, 0.002%≦Ca, O≦0.0015% by weight; the “KO oxides” cleanness index is less than 30, all the oxides are lime aluminates, and the average calcium content of type 2, type 3, type 4 and type 5 inclusions is less than 30%. A process of manufacturing such steel and an oxide-core wire for its manufacture are also provided.

Abstract: A carbon or low-alloy steel is provided with improved machinability. The carbon content of the steel is less than 1.5% and the sum of the alloy elements contained therein is less than 9%. The steel contains oxide and sulfide inclusions, and the chemical composition of the steel includes 0.1%≦Mn, 0.01%≦Al≦0.05%, 0.025%≦S≦0.3%, 0.002%≦Ca, O≦0.0015% by weight; the “KO oxides” cleanness index is less than 30, all the oxides are lime aluminates, and the average calcium content of type 2, type 3, type 4 and type 5 inclusions is less than 30%. A process of manufacturing such steel and an oxide-coated wire for its manufacture are also provided.

Abstract: The invention concerns the adjustment of the linear distribution of an injected shearing fluid, during casting, through a slot (20) provided in the cooled metal body (1)—refractory riser block (14) interface of an ingot mold for continuous metal casting charge and emerging along said ingot inner periphery, the latter being provided with clamping means for adjusting the slot thickness. The invention is characterized in that it consists in “cold” injecting through said slot (20) a regulating inflammable fluid, which is ignited on its exit from the slot, and in acting on the clamping means (25, 26, 28, 29) such that the height of the flames (39) coming out of the slot (20) is substantially constant along the whole ingot inner periphery. The invention provides the advantage of an accurate and lasting adjustment of the injected flow rate without requiring the adjustment of the injection slot thickness. The invention is applicable to continuous steel charge casting in particular.

Abstract: Forged connecting rod, in particular of an internal combustion engine, including a body (1), a connecting rod small end (2) and a connecting rod big end (3), forming two connecting rod small end and connecting rod big end bearings for receiving respectively a piston pin and a crankpin. The connecting rod is constituted by two half connecting rods (5) which are substantially symmetrical relative to a longitudinal median plane (6) of the connecting rod, which plane contains the longitudinal axis of the connecting rod, the joint surface (9) of the half connecting rods being essentially disposed in the median plane (6), the half connecting rods (5), each of which has a connecting rod half bearing (7) and a connecting rod big end half bearing (8).

Abstract: Forged connecting rod, in particular of an internal combustion engine, including a body (1), a connecting rod small end (2) and a connecting rod big end (3), forming two connecting rod small end and connecting rod big end bearings for receiving respectively a piston pin and a crankpin. The connecting rod is being constituted by two half connecting rods (5) which are substantially symmetrical relative to a longitudinal median plane (6) of the connecting rod, which plane contains the longitudinal axis of the connecting rod, the joint surface (9) of the half connecting rods being essentially disposed in the median plane (6), the half connecting rods (5), each of which has a connecting rod half bearing (7) and a connecting rod big end half bearing (8).

Abstract: A carbon or low-alloy steel is provided with improved machinability. The carbon content of the steel is less than 1.5% and the sum of the alloy elements contained therein is less than 9%. The steel contains oxide and sulfide inclusions, and the chemical composition of the steel includes 0.1%≦Mn, 0.01%≦Al≦0.05%, 0.025%≦S≦0.3%,0.002%≦Ca, O≦0.0015% by weight; the “KO oxides” cleanness index is less than 30, all the oxides are lime aluminates, and the average calcium content of type 2, type 3, type 4 and type 5 inclusions is less than 30%. A process of manufacturing such steel and an oxide-core wire for its manufacture are also provided.

Abstract: Steel for the manufacture of a component for bearings, the chemical composition of which comprises, by weight: 0.6%.ltoreq.C.ltoreq.1.5%; 0.4%.ltoreq.Mn.ltoreq.1.5%; 0.75%.ltoreq.Si.ltoreq.2.5%; 0.2%.ltoreq.Cr.ltoreq.2%; 0%.ltoreq.Ni.ltoreq.0.5%; 0%.ltoreq.Mo.ltoreq.0.2%; 0%<Al.ltoreq.0.05%; S.ltoreq.0.04%; the balance being iron and impurities resulting from smelting and the composition furthermore satisfying the relationships: Mn.ltoreq.0.75+0.55.times.Si and Mn.ltoreq.2.5-0.8.times.Si. Process for the manufacture of a bearing component.

Abstract: The mold includes a cooled copper body 4 on top of which sits a refractory feed head 9 which itself consists of two separate components--a thermally insulating upper bush 16 and a bottom annulus 17 made of a stronger and more compact refractory which is surrounded by a crimping ring 18 narrower than the annulus, so that an edge of the annulus extends beyond each side of the ring. As the lower inner edge of the bottom annulus becomes worn due to an erosive flow of molten metal, the working life of the annulus may be extended in two ways. First, the annulus may be removed between casting operations and its bottom surface may be faced. Second, after the facing operations have rendered the bottom surface flush with the crimping ring 18, the annulus may then be inverted so that the lower inner edge is replaced with the upper inner edge.

Abstract: This mold consists of a cooled mold body (1), made of copper or a copper alloy, on which sits a refractory feed head (2) and a purge slit (8) is made at the interface between said mold body and said feed head, via which a stream of a waste inert gas is injected around the internal perimeter of the mold. The slit is supplied via a plenum chamber (13) made within the mold, the plenum chamber being itself supplied with gas via inlets (12) which connect it to a pressurized-gas supply (20). The injection slit (8) is segmented around the mold perimeter with the aid of separating means (21) which also segment the plenum chamber into compartments (13', 13", etc.) which are juxtaposed around the perimeter of the mold so that an inlet (12) runs out into each compartment thus formed.

Abstract: Process for manufacturing a mechanical component made of steel, in which a blank of the steel component is manufactured and a high-temperature carburizing or carbonitriding treatment of at least part of the surface of the blank of the component is carried out, the chemical composition of the steel of which the component is composed comprises, by weight: 0.15%.ltoreq.C.ltoreq.0.35%; 0%.ltoreq.Si.ltoreq.0.6%; 0%.ltoreq.Mn+Cr+Ni+Mo.ltoreq.5%; 0%.ltoreq.Al.ltoreq.0.1%; 0%.ltoreq.Cu.ltoreq.0.5%; 0%.ltoreq.Ti.ltoreq.0.05%; 0.004%.ltoreq.N.ltoreq.0.02%; 0%.ltoreq.S.ltoreq.0.15%; P.ltoreq.0.03%; optionally, up to 0.02% tellurium, up to 0.04% selenium, up to 0.07% lead, up to 0.005% calcium, the balance being iron and impurities resulting from the smelting; the chemical composition being adjusted so that the Jominy curve of the steel is such that: 45 HRC.ltoreq.J.sub.3 .ltoreq.50 HRC; 39 HRC.ltoreq.J.sub.11 .ltoreq.47 HRC; 31 HRC.ltoreq.J.sub.25 .ltoreq.40 HRC; the average values J.sub.3m, J.sub.11m and J.sub.

Abstract: Forged connecting rod, in particular of an internal combustion engine, including a body (1), a connecting rod small end (2) and a connecting rod big end (3), forming two connecting rod small end and connecting rod big end bearings for receiving respectively a piston pin and a crankpin. The connecting rod is constituted by two half connecting rods (5) which are substantially symmetrical relative to a longitudinal median plane (6) of the connecting rod, which plane contains the longitudinal axis of the connecting rod, the joint surface (9) of the half connecting rods being essentially disposed in the median plane (6), the half connecting rods (5), each of which has a connecting rod half bearing (7) and a connecting rod big end half bearing (8).