C21D9/00

Hot-stamped part and method of manufacturing the same

A hot-stamped part includes a chemical composition represented by, in mass %: C: 0.120% to 0.400%; Si: 0.005% to 2.000%; Mn or Cr, or both thereof: 1.00% to 3.00% in total; Al: 0.005% to 0.100%; B: 0.0003% to 0.0020%; P: not more than 0.030%; S: not more than 0.0100%; O: not more than 0.0070%; N: not more than 0.0070%; Ti: 0% to 0.100%; Nb: 0% to 0.100%; V: 0% to 0.100%; Ni: 0% to 2.00%; Cu: 0% to 2.00%; Mo: 0% to 0.50%; Ca or REM, or both thereof: 0% to 0.0300% in total; and the balance: Fe and impurities, and a structure represented by: an area fraction of martensite or bainite, or both thereof: not less than 95% in total; a coverage factor of prior austenite grain boundary by iron-based carbides: not more than 80%; and a number density of iron-based carbides in prior austenite grains: not less than 45/m.sup.2.

PROCESS FOR MANUFACTURING A STEEL SHEET, AND STEEL BELT MADE THEREFROM
20190154111 · 2019-05-23 ·

Manufacturing a steel sheet for a steel belt includes hot rolling a steel slab containing, in mass %, 0.60 to 0.80% of C, 1.0% or less of Si, 0.10 to 1.0% of Mn, 0.020% or less P, 0.010% or less S, 0.1 to 1.0% of Cr, 0 to 0.5% of V, 0 to 0.1% of Ti, 0 to 0.1% of Nb, and 0 to 0.01% of B, the balance Fe and unavoidable impurities, under a finish hot rolling temperature of 800 to 900 C. An average cooling rate from finish rolling to coiling is 20 C. per second or more. A coiling temperature is 450 to 650 C. The hot-rolled slab is cold rolled with a total rolling reduction ratio of 40% or more and a reduction ratio per one pass of less than 12%, without performing a heat treatment. The cold-rolled slab is aged at 200 to 500 C. for 0.5 to 30 hours.

ECONOMICAL PLASTIC TOOLING CORES FOR MOLD AND DIE SETS
20190152106 · 2019-05-23 · ·

A core side of a plastic injection molding tooling set for use in conjunction with a cavity side of the tooling set is disclosed. The core side may have the following composition in percent by weight: 0.25-0.55% carbon, 0.70-1.50% manganese, a maximum of 0.80% silicon, 1.40-2.00% chromium, 0.10-0.55% molybdenum, a maximum of 0.040% aluminum, a maximum of 0.025% phosphorous, a maximum of 0.20% sulfur, a balance of iron, and incidental impurities.

Method of Manufacturing Piercer Plug

A piercer plug having good base-material deformation resistance is provided. A method of manufacturing a piercer plug (10) includes the steps of; preparing a plug body (1) including a tip portion (11) and a cylindrical portion (12) having a hole (121) usable to attach a bar and located rearward of the tip portion (11); forming a build-up layer (2) on the surface of the tip portion (11); and heating the plug body (1) such that the temperature of the tip portion (11) with the build-up layer (2) formed thereon is not lower than the austenite transformation temperature and the temperature of the cylindrical portion (12) is lower than the austenite transformation temperature.

Method for producing a retort for a nitriding furnace and retort

A method for producing a retort for a nitriding furnace, in which metallic workpieces are heat-treated in a pre-determined atmosphere, includes pickling at least the surfaces of the retort, which are configured to come into contact with the pre-determined atmosphere while the nitriding furnace is operating, by using a pickling agent. The pickled surfaces may then be electropolished and passivated. A retort may be produced according to this method and the retort may be used in a nitriding furnace.

Changes enabling the elimination of processes for a torsion bar

In one aspect of the invention, a torsion bar assembly is provided. The assembly includes a first shaft having a first bore, a second shaft having a second bore, the second shaft operatively coupled to the first shaft, and a torsion bar positioned within the first and second bores. The torsion bar includes a splined first end having a first diameter extending to a first end face having a diameter generally the same as the first diameter, a splined second end having a second diameter extending to a second end face having a diameter generally the same as the second diameter, and an active diameter extending between the splined first end and the splined second end. The torsion bar is fabricated from a material having a hardness greater than 45 Rockwell C-Scale.

Cooling element with spacer

A method for producing partially hardened steel components in which a blank composed of a hardenable sheet steel is subjected to a temperature increase and shaped into a component; the component is transferred to a tool in which the heated component is cooled and thus quench hardened; during the heating of the blank or component in order to achieve the temperature increase to a temperature required for the hardening in regions that are to have a lower hardness and/or higher ductility, cooling elements are spaced apart from the surface by a small gap; the cooling element is dimensioned so that the thermal energy acting on the region that remains ductile flows through the component into the cooling element, characterized in that in order to space the cooling element apart from the component, micro-nubs or knobs are used, which are distributed over the area of the cooling element.

Copper alloy for electronic and electrical equipment, plastically worked copper alloy material for electronic and electrical equipment, and component and terminal for electronic and electrical equipment

The present invention provides a copper alloy for electronic and electronic device which has excellent mechanical properties and is capable of suppressing generation of defects even in a case in which the copper alloy is worked to a thin plate thickness or a smaller wire diameter than in the related art, a plastically-worked copper alloy material, and a component and a terminal for electronic and electronic device. The copper alloy for electronic and electronic device of the present invention includes Mg in a range of 1.3 mass % to 2.8 mass % with a remainder substantially being Cu and inevitable impurities, in which a content of H is set to 10 mass ppm or lower, a content of O is set to 100 mass ppm or lower, a content of S is set to 50 mass ppm or lower, and a content of C is set to 10 mass ppm or lower.

Plastic injection mold tooling and a method of manufacture thereof
10294538 · 2019-05-21 · ·

Uniform hardenability is achieved in plastic injection mold and die block tooling of 20 inches and larger by the use of 0.05-0.20 vanadium in conjunction with low carbon steel in which ingots are hot worked to form mold and die blocks having cross sections of 20 inches and larger followed by water quenching and tempering.

Method of annealing aluminium alloy sheet material

A method for continuously annealing aluminum alloy sheet at final thickness by continuously moving heat-treatable AlMgSi aluminum alloy sheet through a continuous annealing furnace arranged to heat the moving aluminum sheet to a set soaking temperature (T.sub.SET) in the temperature range of 500 C. to 590 C., the continuous annealing furnace has an entry section and an exit section, the moving aluminum sheet moves substantially horizontally through the continuous annealing furnace, wherein the moving aluminum sheet is rapidly cooled on leaving the exit section, wherein before or near the entry section of the continuous annealing furnace the moving aluminum sheet is pre-heated to a temperature of 5 C. to 100 C. below the T.sub.SET using an average heat-up rate as function of sheet thickness of at least Y=31.Math.ln(X)+50, wherein Y is the heat-up rate in C./sec and X is the sheet thickness in mm.