Showing papers on "Carbon steel published in 1982"

Hydrogen trapping phenomena in carbon steel

Abstract: Hydrogen trapping phenomena in carbon steel with different amounts of trapping sites were investigated by thermal analysis and permeation experiments. In thermal analysis, the relative amount of trapped hydrogen and the activation energy for evolution from various lattice defects were calculated by monitoring the pressure change caused by the release of hydrogen from hydrogen-charged specimens heated at a uniform rate. Hydrogen release peaks were observed at 116, 205 and 387° C, respectively, when the hydrogen-charged specimens with various defects were heated at a constant heating rate of 2.6° C min−1. Analysis suggested that the peak at 116° C corresponded to release from ferrite-cementite interfaces and the peak at 205° C corresponded to release from dislocations. The activation energy for evolution of trapped hydrogen determined experimentally from the measured peak temperature at different heating rates was found to be 18.4 kJ mol−1 in the ferrite-cementite interface. The hydrogen energy level around the trapping site was suggested from the trap activation energy and expected saddle-point energy. It was observed that most of the hydrogen is trapped in dislocations in spheroidized 0.49 wt% carbon steel.

Iron nitride and carbonitride phases in a nitrogen implanted carbon steel

Abstract: Iron nitride and carbonitride phases formed during nitrogen implantation and subsequent thermal annealing of a medium‐carbon steel are investigated by means of conversion electron Mossbauer scattering. The results are compared to previous work on similar systems and also discussed in terms of the mechanical properties of ion implanted steels.

Loss separation measurements for several electrical steels

Abstract: Loss separation measurements were made on regular grain oriented 3% Si steels of four sheet thicknesses, one thickness of high permeability oriented 3% Si steel, two grades of nonoriented Si steel, a low carbon steel, a primary recrystallization oriented low alloy iron sample, and an amorphous metal sample. The Bn dependence of hysteresis loss Ph for all samples except the oriented Si steels was close to n=1.6, in good agreement with the Steinmetz value. All the oriented Si steels had n values close to 2.

Thermal effects during uniaxial straining of steels

Abstract: When metals are deformed, most of the strain energy absorbed is converted to heat resulting in a temperature increase. Such temperature increases could affect mechanical properties during forming operations and were studied during rapid uniaxial tensile straining at strain rates of 3 x 103 and 10–2 s–1 in a dual phase steel, a high strength low alloy (HSLA) steel, and a plain carbon steel, using an infrared thermometer. The maximum temperatures observed were directly related to the strain energy absorbed, as measured by the area under the stress-strain curve. The dual phase steel absorbed the largest amount of strain energy and therefore registered the largest temperature increase. However, the observed temperature increases were lower than those predicted by calculations assuming adiabatic heating, indicating that such heating did not occur at the strain rates studied.

Impact Strength of Steel Plates Struck by Projectiles : Evaluation Formula for Critical Fracture Energy of Steel Plate

Abstract: In order to clarify the strength of structures which require leak tightness, when struck by projectiles, a series of impact tests for steel plates have been carried out. Cylindrical, semi-spherical and conical-nosed SUS304 stainless steel projectiles were impacted onto carbon steel target plates 7∼38 mm thick. Test results showed that critical fracture energies of target plate by cylindrical and semi-spherical -nosed projectiles mostly agree with the values predicted by empirical formulas generally used, however, the critical fracture energy of target plate by a conical-nosed projectile is fairly smaller than these values. An evaluation formula for the critical fracture energy of target plate, applicable to three kinds of nose shaped projectiles, has been derived from the test results.

High strength, low carbon, dual phase steel rods and wires and process for making same.

Abstract: A high strength, high ductility, low carbon, dual phase steel wire, bar or rod and process for making the same. The steel wire, bar or rod is produced by cold drawing to the desired diameter in a single multipass operation a low carbon steel composition characterized by a duplex microstructure consisting essentially of a strong second phase dispersed in a soft ferrite matrix with a microstructure and morphology having sufficient cold formability to allow reductions in cross-sectional area of up to about 99.9 %. Tensile strengths of at least 120 ksi to over 400 ksi may be obtained.

Measurement of acoustoelastic coefficients of Rayleigh waves in steel alloys

Abstract: An ultrasonic technique to determine the acoustoelastic coefficients of Rayleigh waves in steel alloys is described. The technique is based on the measurement of the time of flight of Rayleigh waves over a fixed surface distance as a function of applied stress. Measurements on AISI 1080 carbon steel, AISI 4130 alloy steel, and 316L stainless steel specimens are reported. Time of flight resolution and repeatability as well as temperature effects are discussed insofar as they influence the applicability of ultrasonic methods to the measurement of applied and residual biaxial surface stresses in steel.

Mossbauer surface study of a nitrogen implanted medium carbon steel

Abstract: The effect of nitrogen implantation on C40 medium-carbon steel is investigated by means of Mossbauer electron backscattering spectroscopy. Samples were implanted at various doses, after quenching from the austenitizing temperature and after quenching plus tempering, in order to detect the influence of the structure previous to the implantation. A different sequence of surface compound formation is observed in the two considered cases.

Titanium clad steel

Abstract: PURPOSE:To obtain a Ti clad steel having enough joint strength, by using steel as a base material, Ti or a Ti alloy as a material to be joined, a first layer of Nb or an Nb alloy and a second layer of Cu or a Cu-Ni alloy as intermediate joining materials, which are hot rolled. CONSTITUTION:The material 1 that is to be joined and comprises industrial pure Ti or a Ti alloy such as Ti-0.15Pb, Ti-V alloy, the first layer intermediate joining material 2 that comprises industrial pure Nb or a Nb alloy containing 60% or more Nb, the second layer intermediate joining material 3 that comprises industrial pure Cu, a Cu alloy containing 50% or more Cu, or a Cu-Ni alloy containing 30-90% Cu and 10-70% Ni and the base material that comprises plain carbon steel or a low alloy steel are heated to about 800-900 deg.C, and then are hot rolled at about 475-900 deg.C at a rolling reduction >=1.5 to obtain the Ti clad steel sheet having enough joint strength and capable of being readily bent. Said clad steel sheet can be subjected to high temperature heat treatment so that the physical characteristics may be improved.

Low alloy or carbon steel roll with a built-up weld layer of an iron alloy containing carbon, chromium, molybdenum and cobalt

Abstract: A roll of which surface cracks are hardly caused under the condition of repetitive heating and cooling. A roll comprises that the alloy consisting of no more than 0.10 percent by weight of carbon, 10˜14 percent by weight of chromium, 0.1˜1.0 percent by weight of molybdenum, 0.5˜2.0 percent by weight of cobalt and essentially balanced iron is coated on the surface of a roll body consisting of low alloy or carbon steel by build-up welding. Therefore, build-up welding layer of the above-mentioned compositions excel in view of resistance to corrosion, and that fact is related with a long-life of a roll.

Process for continuously annealing a cold-rolled low carbon steel strip

Abstract: A cold-rolled low carbon steel strip is continuously annealed by rapidly heating the steel strip with a gaseous combustion product which has been prepared at a combustion air ratio of 0.8 or more but less than 1.0 in a direct fired furnace to a temperature of 500° C. to an Ac 3 point of the steel strip at an average heating rate of 30° to 100° C./sec to cause the thickness of a layer of oxides produced on the peripheral surface of the steel strip not to exceed 1,000 angstroms; by maintaining the temperature of the rapidly heated steel strip in a range of from 700° C. to the Ac 3 point, in a reducing atmosphere comprising 4% or more of hydrogen and the balance nitrogen, for at least 10 seconds, to reduce the oxide layer; by cooling the steel strip from at least 600° C. to a desired temperature, at an average cooling rate of 10° to 300° C./sec by using a cooling medium comprising a gas and a liquid; and by eliminating an oxide layer formed on the peripheral surface of the steel strip during the cooling procedure.

Steel corrosion protected members

Abstract: A steel corrosion-protected member such as a reinforcing bar, a rock anchor, tie bar or prestressing tendon comprises a core of carbon or alloy steel with a cladding of stainless steel or copper. A number of methods of applying the cladding are described including inserting a mild steel rod or bar into a stainless steel tube and hot rolling the rod and tube together to reduce diameter and apply the usual rib pattern. Alternatively a composite billet may be extruded and then rolled down to size. The resulting reinforcing bar shows a carbon steel core (100) to which is welded by pressure a stainless steel cladding (101) with ribs (107). A rock anchor is also described which has a core of carbon or alloy steel clad with stainless steel and includes a threaded end formed on the stainless steel.

Antifouling metallic material

Abstract: PURPOSE: To obtain the antifouling metallic material having an excellent antifouling property and natural electrode potential nearly equal to or lower than those of carbon steel, cast steel and cast iron, by forming said material out of the specified amounts of In and Sn. CONSTITUTION: The composition of the antifouling metallic material is made as follows; by wt% 0.005W50 In, and the balance Sn and inevitable impurities; 0.005W50 In, Zn<30, and the balance Sn and inevitable impurities; or 0.005W50 In, Zn<30, Cu<10, and the balance Sn and inevitable impurities. Since this antifouling metallic material has natural electrode potential equal to or lower than those of carbon steel, cast steel and cast iron, the galvanic corrosion of a structural body is eliminated by attaching the antifouling metallic material to it. Hence, it is not necessary to apply electric insulation between the structural body and the antifouling metallic material. In addition, said metallic material has an excellent antifouling property, too. COPYRIGHT: (C)1984,JPO&Japio

Effects of atmosphere on flank wear of high-speed steel tools used to turn medium-carbon steel in built-upedge conditions

Abstract: The effect of atmosphere on the flank wear of high-speed steel tools under conditions of built-up-edge formation has been studied in a series of turning tests. Four sintered high-speed steels and a wrought M2 were used to turn an En 8D steel bar with a water-based coolant applied alone, with nitrogen and with oxygen blown into the flank crevice while maintaining the flow of water-based coolant on the rake face, and without coolant in air. Tool wear was observed metallographically, and a subsidiary study made of the stability of built-up edges. In dry conditions high adhesion between the built-up edge and the flank produced a cracked and torn wear surface, but a stationary layer also formed which protected the flank from sliding wear. With coolant alone, lesser adhesion resulted in a smooth wear surface but the stationary layer was not formed; overall there was more wear than in dry conditions. The addition of nitrogen to the flank region in wet-cutting tests resulted in a torn wear surface, demons...

The Oxidation of Fe3O4 on Iron and Steel Surfaces

Abstract: Infrared and Raman spectroscopy were used to study the oxidation of Fe3O4 on surfaces of weathering steel, carbon steel, and pure iron. Two sets of samples were polished and coated with an Fe3O4 paste. One set was moistened daily with distilled water and allowed to freely dry in air. The second set was treated in a similar manner except that every other day, a 0.1M Na2SO4 solution was used in place of the distilled water solution. In the set of samples treated only with distilled water, Fe3O4 was oxidized to γ-FeOOH on both the weathering and carbon steel surface, but oxidation of Fe3O4 was not observed on the pure iron surface. On all of the samples treated with 0.1M Na2SO4, Fe3O4 was oxidized initially to γ-FeOOH which converted to α-FeOOH after several weeks. The initial oxidation of Fe3O4 is proposed to occur by a reaction with H2O2 produced from the reduction of O2.

Steel for cold plastic working

Abstract: High-strength, high-workability steel for cold plastic working, obtained by subjecting a hardenable carbon steel to rapid high-frequency induction heating, quenching it, rapidly heating it by high-frequency induction to a temperature of 300°-600° C., and rapidly cooling it. This steel can be cold plastic worked, and then reheated at 300°-500° C. for 30-60 minutes, to obtain a steel having a high elastic limit.

Structure and properties of low-carbon steel alloyed with boron and copper

Abstract: 1. Adding as much as 0.5% Cu to steel microalloyed with boron (as much as 0.003%) increases the solubility of boron in austenite and prevents precipitation of brittle boron-containing phase in austenite grain boundaries. This simplifies the melting procedure for steels with boron. 2. In steels with a higher boron content (0.003–0.005%) that are additionally alloyed with copper the borides are evenly precipitated within grains and in grain boundaries as small equiaxed inclusions. No boride phase was detected in cast or rolled steel with 0.003% B and 0.41% Cu. 3. Adding copper to steel with boron increases the stability of supercooled austenite somewhat and has no negative effect on the hardenability of the steel. 4. After heat treatment, steel with boron and copper has higher values of the strength and especially the fracture toughness as compared with steel with boron but without copper. The ductility of the steel with both additions is fairly high and approaches that of unalloyed steel as the tempering temperature is raised. Adding copper lowers the ductile-brittle transition temperature of steel containing boron.