Showing papers on "Weldability published in 1985"

Surface properties of liquid metals and their effects on weldability

Abstract: The levitating–drop method has been used to determine surface tension as a function of temperature for four transition metals, and also for samples of type 316 stainless steel which exhibited variable weld penetration during tungsten-inert-gas welding. The results obtained verify the predictions of weld-pool models in that the differences in weldability of the steels can be related to the surface properties of the melts. To obtain good weldability in type 316 steels, it is necessary to ensure that the concentration of uncombined surface-active elements (such as sulphur) should exceed a specified minimum level. An indication of the amounts required for consistent weld penetration is given.MST/194

The weldability of lithium-containing aluminium alloys

Abstract: Lithium-containing aluminium alloys have reduced density and increased elastic modulus compared with conventional aluminium alloys. Many such alloys are currently under development for aircraft applications, which usually involve mechanical fastening. Consequently, the weldability of lithium-containing aluminium alloys is currently receiving relatively little attention. The weldability of lithium-containing aluminium alloys is reviewed. The vast majority of the welding studies performed have been on the Soviet Al-5 wt% Mg-2 wt% Li alloy, 01420. Alloy 01420 and other lithium-containing aluminium alloys are indeed fusion weldable, and weldments having high joint efficiencies have been made.

Characterization of Plasma-sprayed Zirconia Coatings by X-ray Diffraction and Raman Spectroscopy(Materials, Metallurgy & Weldability)

Abstract: Three zirconia ceramics, ZrO2−4.5mol.%Y2O3, ZrO2−12mol.%Y2O3 and ZrO2−8mol.%MgO, were investigated using X-ray diffraction before and after plasma spraying. The amounts of monoclinic, tetragonal and cubic phases existing in the three zirconia ceramics were determined from the integrated intensity ratios in the {400} and {111} regions of the X-ray diffraction patterns. The tetragonal-to-monoclinic transformation in the plasma-sprayed coatings caused by indentation, fracture and/or heat treatment with a laser beam was examined using Raman spectroscopy. As a result, this spectroscopic technique is shown to be a powerful tool for the observation of this transformation.

Ferritic-austenitic stainless steel

Abstract: The present invention presents a ferritic-austenitic Cr-Ni-N-Steel alloy with a stable austenite phase, high corrosion resistance and good weldability, said steel alloy consisting essentially of the following elements by weight; max 0.06% C, 21-24.5% Cr, 2-5.5% Ni, 0.05-0.3% N, max 1.5% & Si, max 4.0% Mn, 0.01-1.0% Mo, 0.01-1.0% Cu, the remainder being iron and normal impurities, the contents of said elements being balanced so that the ferrite content, α, amounts to 35-65%. The analysis of the steel is so optimized that it becomes especially useful for those environments where the steel is exposed to temperatures above 60° C. and chloride amounts up to 1000 ppm while the alloy being stable towards deformation form austenite into martensite at a total deformation oft 10-30% in room temperature.

Fundamental aspects of formation and stability of explosive welds

Abstract: fundamental bonding processes that occur between two metals over an explosive weld interface are described. As a physical model for interfacial bonding, Miedema’s model for alloy formation is employed, 14, 15 generalized from interatomic to macroscopic interfaces. Formation energies for metal-to-metal interfaces are calculated for a large number of metal combinations. The theoretical bond strengths, together with weldability factors, are compared with practical experience for a number of metal combinations, yielding a relatively good agreement. Other interface phenomena such as interface alloying and segregation are also treated by the present model, and for the metal systems studied, theory and experimental results were found to agree well.

Rare Earth Additions in Continuously Cast Steel

Abstract: Rare earth (lanthanide metals) addiiions to continuously cast steel are particularly advantageous because of their ability to refine as-cast structures, reduce segregation and increase hot ductility at temperatures just below that of solidification. The complete shape control of sulfides in steels containing Rare Earth Metals (REM), whether continuously cast or ingot cast, is primarily responsible for improvements in ductility related mechanical properties, weldability, fatigue resistance and resistance to hydrogen damage. Complete sulfide shape control can be obtained with REM additions at sulfur levels as high as.020%. The greatest improvements, however, are obtained with REM additions to low sulfur steels. However, to achieve full operational advantages afforded by REM, nozzle blockage problems must be circumvented. Water model studies indicate a possible solution.

Method for surface treatment of electrical steel sheet

Abstract: The insulating film comprised mainly of phosphate or chromate is improved in its insulation property required for the laminated core e.g., a transformer, the blanking property required for manufacturing the core sections from the electrical steel sheet, and the lamination weldability. The organic resin particles used for controlling the surface roughness of the film are preliminarily treated with a dispersion improver, and then added to the emulsion resin, which is then mixed with the phosphate or chromate.

Gas shielded arc welding method

Abstract: PURPOSE: To execute welding of good mechanical properties with high efficiency with extremely few defects by using a flux-cored wire contg. specific ratios of components to weld steel plates having non-cleaned surfaces and welding these steel plates in an independent gas of CO 2 , Ar or H 2 contg. a specific ratio of O 2 or a gaseous mixture composed thereof. CONSTITUTION: The flux-cored wire contg. 0.2% C, 0.3W1.5% Si, 0.5W3.0% Mn and 0.5W8.5% TiO 2 to improve the mechanical properties and appearance of weld zones A, B is used for welding A, B of the steel plates 1, 2 having the non-cleaned surfaces such as painted or rusted surfaces. Other elements to reinforce the weld zone, for example, Ni, Cr, etc. may be incorporated in the wire at the specific ratio or below and Bi, Pb, etc. contributing to the improvement of weldability may also be incorporated therein. The steel plates are welded by using such flux-cored wire in the independent gas of CO 2 , Ar or H 2 contg. ≥5vol.% O 2 or the gaseous mixture composed thereof. The welding of the good mechanical properties with the extremely few pits and blowholes is thus executed with good workability. COPYRIGHT: (C)1986,JPO&Japio

Method for producing a thin tin and nickel plated steel sheet for welded can material

Abstract: A method for producing a thin tin and nickel plated steel sheet having a surface structure in which the distribution of numerous nodules of metallic tin are observed by using an electron microscope on an iron-tin-nickel alloy layer formed on a steel sheet which comprises electroplating nickel on the steel sheet which is anodically treated in an alkaline electrolyte with a pH of above 10 followed by electrotinplating the nickel plated steel sheet, reflowing, quenching, and then chromate treating the tin and nickel plated steel sheet. This tin and nickel plated steel sheet is suitable for welded can materials since it is excellent in corrosion resistance after lacquering and weldability.

Low alloy steels for use in pressure vessels

Abstract: Low alloy steels for use in pressure vessel comprising on the weight % basis: C: from 0.05% to 0.30%, Si: less than 0.10%, Mn: from 0.3% to 1.5%, Ni: from inevitably incorporated content to 0.55%, Cr: from 1.5% to 5.5%, Mo: from 0.25% to 1.5%, V: in excess of 0.10% and less than 0.6%, and the balance of iron and inevitably incorporated impurities. The steels are excellent in hardenability, the hot strength, toughness weldability and hydrogen attack and embrittlement resistance, as well as show excellent toughness after the use in the temper brittle temperature region.

Welding material having excellent creep rupture ductility

Abstract: PURPOSE:To obtain a welding material having excellent creep rupture ductility and good weldability with a specifically composed welding mterial for a super heat resistant alloy for an intermediate heat exchanger of a multi-purpose high- temp. gas experimenting furnace by limiting the copper in unavoidable impurities. CONSTITUTION:A welding material of the above-described super heat resistan alloy (''Hastelloy X'') is formed of the compsn. contg., by weight %, 0.04-0.15 C, 20.0-25.0 Cr, 17.0-20.0 Fe, 8.0-10.0 Mo, 0.2-1.0 W, 0.4-1.5 Mn, 0.05-0.5 Si and 0.5-2.5 Co, contg. >=1 kind among <=0.02 B, <=0.05 Zr, <=0.02 Mg, <=0.02 Ca and <=0.02 rare earth elements and consisting of the balance ni and unavoidable impurities. The contents of Al, Ti, Cu as unavoidable impurities are limited to <=0.1 Al, <=0.02 Ti and <=0.05 Cn. If the content of Cu is limited to <=0.05wt% in such a way, the creep rupture ductility is improved and the deterioration in weldability owing to addition of B, Zr and rare earth elements is obviated as well.

Welding and weldability of nickel-iron aluminides

Abstract: An important area in the development of any commercial alloy is the ease with which it may be joined or welded. A study was undertaken to investigate the weldability of the borondoped (500 ppm by weight) ductile aluminides by gas tungsten arc (GTA) and electron beam (EB) welding processes. Autogenous GTA welding of boroncontaining nickel-iron aluminides produced severe cracking within the weld metal and the heat-affected zone (HAZ). The hot cracking appears to be related to complex phase changes that the material undergoes at elevated temperatures in the HAZ and also during the liquid-tosolid transformation in the fusion zone. A series of EB welds with welding speeds ranging from 13 to 64 mm/s (30 to 150 ipm) with varying beam focus conditions gave successful complete joint penetration welds only in a narrow range of speeds and focus conditions. The cracks were predominantly intergranular in the HAZ and interdendritic in the fusion zone presumably associated with the presence of NiAl (..beta..') phase along the grain boundaries and interdendritic regions. Transmission electron microscopy (TEM) revealed tetragonal distortions of the ordered B2 (NiAl type) phase with a martensitic appearance. Microprobe analysis revealed extensive solute redistribution in the fusion zone and the HAZ asmore » a result of the weld thermal cycle.« less

Cold rolled steel sheet for enamel and its production

Abstract: PURPOSE: To provide a cold rolled steel sheet having improved press formability, enamel adhesiveness and fishscaling resistant characteristic and excellent weldability by adding particularly a prescribed ratio each of Se and/or Te to a Ti-added steel. CONSTITUTION: This cold rolled steel sheet contains, by weight %, ≤0.005% C, ≤0.02% P, ≤0.03% S, 0.005W0.012% N and ≤0.15% Ti, has the relation expressed by the formula, contains ≤0.08% Cu, contains particularly 0.003W0.05% Se and/or Te and consists of the balance Fe and unavoidable impurities. The above-mentioned formula is Ti≥(4B/12C+4B/14N+4B/32S)%. The production of the cold rolled steel sheet is characterized by casting continuously the molten steel having the above-mentioned component compsn. and subjecting the cast steel to hot rolling and cold rolling then to continuous annealing in the temp. region of the recrystallization temp. or above and the Ac 3 point or below. The cold rolled steel sheet for enamel having the excellent press formability, enamel characteristic and weldability is thus obtd. COPYRIGHT: (C)1986,JPO&Japio

Manufacture of wear resistant steel sheet having satisfactory weldability

Abstract: PURPOSE: To obtain a low-cost wear resistant steel sheet having satisfactory weldability by subjecting a steel having a prescribed composition contg restricted amounts of C, Cr and Mo which deteriorate weldability to quenching and tempering under specified conditions CONSTITUTION: A steel consisting of 010W019% C, 005W055% Si, 090W160% Mn and the balance Fe and having 035W044% Ceq represented by the formula is prepd The steel is hot rolled, quenched directly from 950W850°C or quenched after reheating to 900W950°C and tempered at 300W500°C Thus, a wear resistant steel sheet having superior bendability and causing no weld crack is obtd The steel sheet is suitable for construction and transfer machinery such as a power shovel COPYRIGHT: (C)1987,JPO&Japio

Manufacture of wire rod for long-sized high tension steel wire

Abstract: PURPOSE:To easily manufacture a wire rod suitable for a deformed wire for a submarine cable by welding wire rods formed by the hot rolling of steel ingots having a specified and by heat treating the weld zone of the resulting long-sized wire rod under specified conditions to form a fine ferrite-pearlite structure. CONSTITUTION:Steel ingots having a composition consisting of, by weight, 0.30-0.65% C, >=1.0% Si, 0.3-1.5% Mn, =0.75% Ceq [Ceq=C+1/5(Mn+Cr)] are hot rolled to form wire rods. The wire rods are welded and the weld zone of the resulting long-sized wire rod is heated, held at a temp. in the austenite range and cooled at 3-20 deg.C/sec cooling rate to form a ferrite-pearlite structure. Thus, a wire rod for a long-sized high tension steel wire having superior weldability and cold workability is obtd.

Method for producing high-strength steel having improved weldability

Abstract: METHOD FOR PRODUCING HIGH-STRENGTHSTEEL HAVING IMPROVED WELDABILITY ABSTRACT OF THE DISCLOSURE High-strength steel having a tensile strength of 80 kgf/mm2 or more is produced by on-line quenching or on-line quenching and tempering. The steel has also excellent low-temperature toughness and excellent weldability, which makes high temperature preheating unnecessary prior to welding. The composition is:C = 0.04% to 0.11%; Si ? 1.0%; Mn = 0.5% to 2.00%;Mo = 0.10% to 1.0%; Nb = 0.005% to 0.05%; B ? 0.01%;Al ? 0.1%; and N ? 0.0060%.

Production of thin sn-plated steel sheet for can making

Abstract: PURPOSE: To inexpensively produce an Sn plated steel sheet having excellent seam weldability and corrosion resistance under a coated film by forming an Sn plating layer of adequate deposition on the steel sheet then subjecting the plating layer to a heating treatment to adequately control the form and distribution condition of the residual unalloyed β-Sn layer. CONSTITUTION: Sn plating coating is formed on the steel sheet at ≤1,500mg/m 2 per side. The Sn plated steel sheet is thereafter subjected to the melting treatment of the Sn plating layer by the heating treatment to the m.p. of the Sn plating layer or above. The treatment is so executed that the remaining unalloyed β-Sn layer has the coarse Sn grains having ≥100 pieces for each 0.1mm 2 of projecting parts sized ≤30μm max. diameter. The surface treated steel sheet for can making having the excellent seam weldability and corrosion resistance under the coated film is thus obtd. The seam weldability is further improved by coating of Ni or an Ni alloy layer contg. ≥1 kinds of Fe, P, Zn, Cu and Cr in Ni as the underlying plating for the above-mentioned Sn plating layer at ≤100mg/m 2 in terms of Ni and further subjecting the coating to a diffusion treatment by a heating treatment according to need. COPYRIGHT: (C)1987,JPO&Japio

Production of steel sheet for can vessel having excellent weldability and painting performance

Abstract: PURPOSE:To produce a steel sheet for a can vessel having excellent weldability and painting performance by electroplating Ni onto a steel sheet then heating the sheet to penetrate and diffuse Ni into the steel, subjecting the plated steel sheet to required rolling and further to electroplating of Sn and chromating. CONSTITUTION:A cold rolled steel sheet havng the component compsn. adequate as a can vessel is subjected to Ni plating with 30-500mg/m coating weight per side by using a watts bath, etc. and is in succession subjected to a heat treatment at about 500-750 deg.C in a non-oxidizing atmosphere to penetrate and diffuse a part or the whole of the Ni plating layer into the steel, by which the steel sheet is made resistant to corrosion. The steel sheet is then subjected to temper rolling or cold rolling according to need followed by Sn electroplating at 100-15,000mg/m coating weight per side by using a ferrostan bath, etc. to improve the corrosion resistance and appearance. The steel sheet is then electrochromated in a bath contg. 1 or 2 kinds of SO 4 and F at a rate of 1/500-1/50 of the concn. of Cr in an aq. chromate soln., by which the steel sheet for a can vessel having excellent weldability and painting performance such as paintability, corrosion resistance before and after painting, appearance, etc. is obtd.

Tensile Strength of Welded Joints for TMCP Type 50kgf/mm2-Class High Tensile Steel Plates

Abstract: 50 kgf/mm2-class high-tensile steel plate produced by newly developed TMCP (thermo-mechanical control process) is superior to conventional rolled steel plate in weldability (resistance to low-temperature cracking) as well as in toughness of HAZ of the high heat-input welded joint.However, HAZ of high heat-input welded joint softens because of the low carbon equivalent.The authors investigated the tensile strength of the welded joint with soft HAZ in ship hull and other heavy steel structures.As a result, it was found that even with the maximum heat-input welding process prevalently in use in most of the domestic ship-yards, the tensile strength of the welded joint thereby produced in wide plate would be 50 kgf/mm2 or more and approximate that of the base metal when Ceq. _≥0.23%.

Electrolytically chromated steel sheet having excellent weldability and its production

Abstract: PURPOSE: To produce the titled steel sheet having excellent welability by successively forming a metallic chromium layer and a hydrated chromium oxide layer in respective specified amts. on the surface of a steel sheet and uniformly distributing many protrusions on the metallic chromium layer. CONSTITUTION: A metallic chromium layer 2 is formed in the amt. of 5W200mg/m 2 on the surface of a steel sheet 1 and a hydrated chromium oxide layer 3 consisting essentially of chromium oxide is formed on the metallic chromium layer 2 in the amt. of 3W30mg/m 2 expressed in terms of metallic chromium. When the metallic chromium layer 2 is formed by the electrolytic chromate treatment, at least one anodic treatment is carried out during the cathodic treatment in the case of one-liq. process and during the cathodic treatment with the first liq. in the case of a two-liq. process. Consequently, many granular or angular protrusions 4 are formed on the metallic chromium layer and uniformly distributed. Besides, the current denstiy in the cathodic treatment is regulated to ≤10A/dm 2 and the quantity of electricity in the anodic treatment is preferably controlled to about 0.01W5 coulumb/dm 2 . By forming a film of such a structure on the steel sheet 1, an electrolytically chromated steel sheet having excellent weldability is obtained. COPYRIGHT: (C)1987,JPO&Japio

Low alloy steel sheet and manufacture

Abstract: Low alloy steel shape of at least 4.8 mm thickness is produced by providing a steel consisting essentially of from about 0.02% to 0.07% carbon, 1.2% to 2.0% manganese, 0.020% maximum sulfur, up to 0.5% silicon, 0.1% to 0.4% molybdenum, 0.01% to 0.1% columbium, about 0.01% to 0.10% acid soluble aluminum, about 0.8% to 2.0% copper, about 0.4% to 2.0% nickel, residual chromium, and balance iron; hot reducing the steel to a desired final thickness with a total reduction in thickness of at least 30% while within the temperature range of about 760 DEG to 927 DEG C whereby to avoid substantial recrystallization of austenite and to obtain a predominant heavily deformed austenite phase; and cooling at a rate which transforms the austenite phase to a predominantly fine acicular ferrite and lower-bainite phase. The steel may also be precipitation hardened, or may be hot reduced either by the above-described controlled hot reduction or by conventional hot reduction, austenitized, quenched, and precipitation hardened. The product has high strength, improved low temperature toughness and excellent weldability.