Showing papers on "Carbon steel published in 1971"

Methods for making bi-metallic pipe

Abstract: A method for making bi-metallic pipe and a bi-metallic pipe are provided in which a strip of carbon steel having fixed thereto a strip of corrosion resistant metal of the same width is spirally wound into a pipe and welded with a first weldment in the corrosion resistant metal extending into the carbon steel and a second weldment in the carbon steel extending into the first weldment.

Multilayer pressure vessel method

Abstract: A multilayer pressure vessel method wherein the vessel has both a multilayer cylindrical body and at least one multilayer head, with an inner shell being formed of stainless steel or other metal resistant to hydrogen embrittlement and with the multilayer body and multilayer head being provided with means for relieving hydrogen pressure in the layers externally of the inner shell, whereby the outer layers may be ordinary carbon steel for both the body and the head without danger of hydrogen embrittlement.

Induction heating method of case hardening carbon steel rod

Abstract: A METHOD OF CASE HARDENING TO A DESIRED DEPTH A ROD FORMED FROM CARBON STEEL WHICH METHOD INCLUDES THE STEPS OF MOVING THE ROD LONGITUDINALLY, INDUCTIVELY HEATING THE ROD AT A RATE THAT CREATES A HEAT PROFILE WITHIN THE ROD WHICH PROFILE EXCEEDS THE UPPER CRITICAL HEATING TRANSFORMATION TEMPERATURE ADJACENT THE SURFACE OF THE ROD AND TO A DEPTH GENERALLY CORRESPONDING TO THE DESIRED DEPTH TO BE HARDENED WITH THE AVERAGE TEMPERATURE OF THE HEATING PROFILE BEING LESS THAN THE LOWER CRITICAL HEATING TRANSFORMATION TEMPERATURE OF THE ROD, ALLOWING THE ROD TO SOAK, AND, THEN QUENCHING THE ROD WITHIN LESS THAN ABOUT 50 SECONDS AFTER THE HEATING STEP.

Method of manufacturing oriented grain magnetic steel sheets

Abstract: METHOD OF ELABORATING METAL SHEETS FOR MAGNETIC APPLICATIONS AND MORE PARTICULARLY SHEETS HAVING A SINGLE OR DOUBLE GRAIN ORIENTATION, WHICH CONSISTS IN ELABORATING A CARBON STEEL HAVING A VERY LOW SULFUR CONTENT, I.E. LESS THAN .005% AND PREFERABLY LESS THAN .003%, REHEATING THIS METAL IN STEELWORK FURNACE AND STRONGLY OXIDIZING THE METAL IN A CONTROLLED MANNER, WHILE AVOIDING ANY RESULFURIZATION, RECARBURIZING THE STEEL IN THE LADLE AND IN VACUUM TO OBTAIN VERY LOW CARBON CONTENTS, PREFEREABLY LESS THAN .005% C. SUBSEQUENTLY ADDING THE NECESSARY ALLOYING ELEMENTS, SILICON AND/OR ALUMINIUM, HOMOGENIZING THIS ADDITION BY STIRRING, CASTING INTO INGOT MOULDS, PREFERABLY WITHOUT AMBIENT AIR CONTACT, THE EXTRA-MILD STEEL THUS OBTAINED, AND FINALLY ROLLING THE RESULTING INGOTS TO CONVERT THEM INTO SHEETS HAVING A SINGLE-OR DOUBLE GRAIN STRUCTURE ORIENTATION.

Columbium treated low carbon steel

Abstract: A process of producing non-aging, low carbon steel having substantially no yield point elongation in the annealed condition and freedom from critical grain growth. A molten steel having an analysis typical of steel intended for rimmed or killed drawing steel is vacuum degassed to decarburize to a maximum carbon content of about 0.015%, and columbium (niobium) is added in an amount at least sufficient to combine with the carbon present in the steel. The cast material is hot rolled, finishing at 1500 DEG - 1700 DEG F (about 1090 DEG - 1200 DEG K) and coiled at a temperature of about 1500 DEG F (about 1090 DEG K) or less. The columbium addition retards the rate of recrystallization of the cold rolled product, and a wide spectrum of mechanical properties can be obtained in the final product by control of the final annealing time and temperature within the range of 1000 DEG to 1700 DEG F (about 810 DEG to 1200 DEG K). A preferred product is cold rolled and annealed strip suitable for deep drawing, porcelain enameling, hot dip metallic coating and the like, containing at least about 0.025% uncombined columbium at the hot rolling stage, as determined by analysis at room temperature, which has an average plastic strain ratio of at least 1.8, and a uniform grain size between ASTM 8 and 10.

Dual property steel armor

Abstract: DISCLOSED IS A DUAL PROPERTY STEEL ARMOR MATERIAL IN THE FORM OF A COMPOSITE, ROLL-BONDED STRUCTURE HAVING AN OUTER OR IMPACT LAYER OF AN IMPROVED ALLOY OF STEEL CAPABLE OF SHATTERING HARDENED STEEL ARMOR PIERCING PROJECTILES AND A HIGH TOUGHNESS BACKING LAYER OF AN IMPROVED ALLOY OF STEEL TO ACHIEVE MULTIPLE STRIKE INTEGRITY. THE OUTER OR IMPACT LAYER IS A LOW CARBON STEEL ALLOY CONTAINING THE CARBIDE FORMING ELEMENTS CHROMIUM, MOLYBDENUM, AND VANADIUM ALONG WITH MANGANESE, SILICON, AND NICKEL. THE HIGH TOUGHNESS BACKING LAYER IS COMPRISED OF A LOWER CARBON CONTENT OF A LOW CARBON STEEL ALLOY THAN STEEL ALLOY USED FOR OUTER IMPACT MATERIAL. THE COMPOSITE STRUCTURE IS PROVIDED WITH IMPROVED BALLISTIC PERFORMANCE THROUGH THERMAL-MECHANICAL PROCESSING OF A PROPERLY CONSTITUTED ALLOY STSTEM.

A Comparison of the Axial and Reversed-Torsional Strain Cycling Low-Cycle Fatigue Strength of Several Structural Materials

Abstract: As a part of series investigation on the low-cycle fatigue properties under the multiaxial stress condition, low-cycle fatigue tests were conducted under axial and reversed-torsion strain cycling conditions. Two kinds of carbon steel, a Ni-Cr-Mo steel, a commercially pure aluminum, a 7075-T6 aluminum alloy, and cold-worked and annealed coppers were tested in this investigation. The equivalent plastic strain range based on the octahedral shear strain theory was used in comparing these axial and reversed-torsional results. In general fairly good agreement was observed between the two cycling results, although some discrepancies existed in the case of the carbon steels and the annealed copper investigated. Some amount of anisotropy was found in fracture ductility between the axial direction and the diametral direction of specimens. This might affect more the reversed-torsion results. For more precise correlation of the two cycling test results, therefore, the influence of the anisotropy as well as that of the crack propagation characteristics should be taken into consideration.

Heat treatment process for non-alloyed low-carbon structural steel

Abstract: A LOW CARBON STEEL CAN BE HEAT TREATED TO IMPROVE EITHER ITS PHYSICAL PROPERTIES OR ITS ELONGATION WITHOUT DETRIMENT TO THE OTHER BY HEATING A SHELL REGION OF THE STEEL QUICKLY AND THEN ALLOWING HEAT TRANSFER TO TAKE PLACE UNTILE THE SHELL TEMPERATURE PREFERABLY DROPS TO THE VALUE OF THE CORE TEMPERATURE WHEREUPON THE STEEL IS INTENSIVELY QUENCHED IN WATER.

Effect of boron on the cold brittleness of medium-carbon steel

Abstract: 1. When alloyed with ∼0.003% B, steel 40GR with a section as large as 40 mm has a higher fracture toughness and lower cold brittleness threshold than steel 40G after quenching and tempering to a hardness of HB 290. 2. After quenching and low-temperature tempering, medium-carbon steel with boron may have a fairly high fracture toughness along with high hardness. 3. To eliminate the high susceptibility of the steel to brittle fracture the boron content should be ∼0.001–0.004%.

Entrapped Scum and Pinholes in Continuously-Cast Carbon Steel Billets

Abstract: Entrapped Scum and Pinholes in Continuously-Cast Carbon Steel Billets Hisashi MORI, Nobuyoshi TANAKA, and Masazumi HIRAI Synopsis: An investigation was done on the entrapped scums and pinholes in continuously-cast plain carbon steel billets of 80 to 160 square and 260 by 370mm section. The results obtained are summarized as follows: 1) The number of entrapped scums in the billets cast with open nozzles and oil was increased with decreasing manganese-to-silicon ratio and carbon content in the steels, excess addition of aluminum wire in a mold, addition of titanium to a low manganese steel, air oxidation of teeming stream in a mold, and increasing billet size. 2) Utilizing submerged nozzles and fluxing powders remarkably removed such scums. 3) These observations are discussed in terms of the melting point, fluidity, interfacial tension, and the amount of scums formed. 4) The number of pinholes in the billets cast with open nozzles and oil was decreased with decreasing carbon content of the steels, by using strong deoxidizers such as aluminum, calcium-silicide, or titanium, protecting air oxidation, drying ferroalloys, and with decreasing billet size. The use of water-free fluxing powders perfectly prevented the formation of pinholes. (Received Nov. 7, 1970)

The rate of formation of intermetallic layers between aluminum and steel below 660°C

Abstract: The rate of formation of intermetallic compounds between aluminum and three ferritic steels, one austenitic steel, and Inconel has been determined by an electrolytic method. The steel was held at zero potential with respect to aluminum in a NaCl-AlCl3 melt, and the current measured. Comparison of measured thicknesses of intermetallic layers with those calculated from the integrated current gives an average deposition efficiency of 95 pct. For the Type 304 austenitic steel thickness \((mm) = k\sqrt {time}\) (min), andk is given by logk= −6400/T(0K) +4.469. The ferritic steels show a linear rate of growth of Al5Fe2, with an initial higher rate such that extrapolation of the linear curve back to zero time gives an intercept of 16±7 μm. The rate constants (mm min−1) may be represented by log (rate)=α/T+β, and the values of α and β are respectively −2650 and−0.788 for a plain carbon steel,−6580 and + 3.469 for a 1.3 pct Cr, 0.4 pct Mo steel, and−5950 and +2.466 for a 2.2 pct Cr, 0.9 pct Mo steel. The more highly alloyed steels are thus attacked, more slowly. Results for Inconel could not be fitted to any simple equation. With the ferritic steels growth is by aluminum diffusing inwards; with Inconel it is by nickel diffusing outward.

The influence of austenisation on the kinetics of tempering—Mössbauer effect study

Abstract: The Mossbauer effect in 57Fe is used to investigate the kinetics of carbide precipitation in plain carbon steel. The investigated carbides were extracted chemically after the steel had been treated at various austenisation and tempering temperatures. The relative amount of cementite precipitated after a certain heat treatment was determined from the spectral area. The activation energy of the process is found to be 0.3 eV. A formula is suggested for the dependence of carbide formation rate on the austenisation temperature. It is found that in the process of the chemical extraction, amorphous iron gel or oxyhydroxide isomers form, rather than iron oxides. The effective internal field Hn and the isomer shift of the extracted carbides depend on the tempering temperature, while the carbide formation rate depends on the austenisation temperature as well.

Method of producing stainless steel-low carbon steel composites

Abstract: Stainless steel-low carbon steel composite sheets are prepared by welding a sheet of stainless steel to one side of a sheet of low carbon steel, the carbon steel sheet being preferably in the form of a tray, depositing many small pieces of low carbon steel scrap (offal) on the carbon steel sheet in a thick, porous layer of uniform thickness, heating the welded sheets and scrap particles to a temperature of about 2000 DEG F., and passing them through at least one set of rollers to weld the low carbon steel scrap into a fully densified, solid layer including the carbon steel sheet and to weld the carbon steel layer to the adjoining stainless steel sheet. The resulting product is a flat-rolled composite sheet wherein the relatively thick low carbon steel portion is simultaneously formed from scrap particles and welded to a thinner stainless steel layer.

Compound cast rolls

Abstract: 1,271,959. Casting composite rolls. HITACHI Ltd. 23 July, 1969 [26 July, 1968; 20 Jan., 1969], No. 37165/69. Heading B3F. A method of making a composite roll comprises positioning a hollow cylindrical partition member in a mould, pouring molten steel into the annular space between the partition member and the mould walls, pouring molten iron or steel into the interior of the partition member, machining the roll and subsequently subjecting the finished roll to a heat treatment. A carbon film may be formed on the surface of the partition member or the surface may be subjected to nitrification or aluminization to facilitate the metallurgical connection between the member and the other parts of the roll. The wall thickness of the partition member varies along its length and it may be mdae up of a plurality of sections welded together. Its surface may have recesses or projections thereon. The outer part of the roll is made from a high alloy steel containing 0A2 to 2-6% of carbon and at leats 3% of alloying elements such as Ni, Cr, Mo, V, Ti, W, Si and Mn; and the inner part and partition member from plain carbon steel, low alloy steel or cast iron. The partition member may extend beyond the body of the roll so as to form the surface of the roll journal. The tensile strength of the partition member is at least 35 kg/mm. 2 , and that of the metallurgical bonds between the partition member and the other parts at least 7 kg/mm. 2

Method for producing low carbon steel with exceptionally high drawability

Abstract: 1339458 Highly drawable steel sheet USS ENGS & CONSULTANTS Inc 19 April 1971 [27 Feb 1970] 22748/71 Heading C7A A slab of a steel comprising:- C 0A03-0A1% Mn 0A005 - less than 0A15% S 0A004-0A03% O less than 0A015% P 0A02% max and Si 0A06% max, the balance, apart from incidental steelmaking impurities (such as Al and Ti), being Fe is a) hot rolled at a sufficient temperature to prevent the formation of proeutectoid ferrite (e.g. with a final pass at 1700‹-1830‹F); b) cold reducing the so-produced sheet by 60-80%; and c) soaking the sheet at 1200‹-1350‹F. for 12-30 hours to give a microstructure with most of the (111) and (112) planes in the plane of the sheet. The slab may be produced by continuous casting, the original steel melt may be treated by vacuum carbon deoxidation to obtain the correct oxygen content and the final sheet product has exceptionally high drawability.

Dissolution of Iron in Sulfuric Acid Solutions

Abstract: A new technique is described for characterizing the specific electrochemical reactivity of metal specimens by measurement of the electrode potential in a reference corrosion medium. The corrosion behavior of iron and low carbon steel specimens thus characterized was studied in sulfuric acid solutions in the absence of an externally applied potential. This method of characterizing the reactivity allows an accurate estimation of the corrosion rate in a broad range of sulfuric acid concentrations for iron and low carbon steels of the usual range of electrode potentials. Within the range of reactivity examined, two principal rate controlling steps were encountered. The nature of the rate controlling step is determined primarily by the electrochemical potential of the specimen and is also influenced by the coverage of atomic hydrogen. A tentative mechanism is proposed to explain the experimental observations.

Electrolytic method and treatment bath for providing chromium-containing protective coatings on steel stock

Abstract: 1,247,881 Electro-depositing chromiumcontaining coatings UNITED STATES STEEL CORP Sept 30, 1968 [Sept 29, 1967], No 46387/68 Heading C7B Flat-rolled steel-base stock, eg a cleaned tin-free carbon steel plate, is provided with a corrosion-resistant coating, comprising a chromium layer eg of weight 0A1-2A0 mg Cr/ft 2 adjacent the stock and a hydrated chromium oxide layer eg containing 0A1-30 mg Cr/ft 2 over-lying the chromium layer, by continuously passing the stock as cathode through an aqueous bath containing 5 to 80 g/l of CrO 3 and 0A25 to 5 g/l of CoCl 2 6H 2 O or sulphamic acid as promoter The cathode current density may be 25 to 300 a/ft 2 for “ to 10 seconds to provide an electrical energy input to the stock of 50 to 1,000 coulombs/ft 2 Lead anodes may be used Prior to the above treatment, the stock may be anodically cleaned, preferably in a bath of the same composition

Solid state method for converting small pieces of steel to a workpiece

Abstract: A method is disclosed for converting scrap or other small pieces of steel into a useful, commercial product while maintaining the steel in a solid state. According to the process, pieces of scrap steel are baled together into a bale in which the scrap pieces of random size and shape become intertwined together. The bales are heated in a reducing atmosphere so that carbon migrates from the scrap steel. The heated bales are impacted, while heated, to produce a steel body which is thereafter subjected to continued impaction so that the pieces forming the body are welded together into cohesive, homogeneous slab of low carbon steel.

Surface hardening of steel by vacuum diffusion chromizing

Abstract: Vacuum diffusion chromizing was studied as a method of increasing fatigue strength and the corrosion and erosion resistance of steel. It was shown that carbon steels chromized by this method can be used in place of stainless chromium-nickel steels.

Electric welding of helically seamed pipes

Abstract: Welding appliance is suitable for non-rusting materials, light-alloyed materials or carbon steel, and is used in two or more welding processes

Effect of vacuum annealing on decarburizing of low-carbon steel

Abstract: 1. Metallographic analysis of a “sloping section” produced quantitative data on the depth of decarburizing of low-carbon steel 11YuA-Sh after annealing in vacuum at different temperatures and times. 2. Noticeable decarburizing of the surface begins at approximately 650°C. 3. Intensive decarburizing in the initial period of heating at 900–1100°C may result from chemical interaction of carbon and oxygen, forming an oxide film on the surface. 4. The rate of decarburizing at annealing temperatures of 1000 and 1100°C (in the γ phase region) is higher than at lower temperatures, although with time the rate decreases and the depth of decarburizing even becomes smaller, which is due to the substantial impoverishment of the surface layer in oxygen. 5. Decarburizing of steel in vacuum is controlled by the diffusion of oxygen in iron. The parabolic variation of the depth of decarburizing with time at 900°C makes it possible to propose that the diffusion coefficient of oxygen in iron at 650–900°C be determined from the depth of decarburizing in low-carbon steel (or from the carbon concentration through the depth of the surface layer on an iron-carbon alloy) after annealing in vacuum.

Rapid Analysis of Mn in Plain Carbon Steels by Nondispersive X-Ray Fluorescence Spectroscopy

Abstract: Plain carbon steels are primarily composed of iron (~ 97%), but generally have small quantities of carbon, manganese, sulfur, phosphorous and silicon also present. Lead or copper may also be present. The steel industry is in need of an on-line technique of analysis for manganese in these steels. The manganese concentration of these steels varies from 0.3 to 1.5%. A technique is presented for the rapid analysis of manganese in carbon steels using energy-dispersive x-ray fluorescence spectroscopy. It is capable of determining the manganese content of a carbon steel in less than 30 sec with an uncertainty of less than 0.05% manganese. Because this method can analyze a steel from a distance of two feet, it should be possible to adequately protect the x-ray fluorescence spectrometer from the environment even when analyses are made of hot steel ingots at temperatures ranging up to 2400°F.