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Showing papers on "Weldability published in 1995"


Journal ArticleDOI
TL;DR: In this paper, a study was undertaken to establish the weldability of high-strength low-alloy steel using austenitic filler metals (309L and 18Cr-8Ni-6Mn) and the gas tungsten welding process with a view to securing high toughness in the weldment.

52 citations


Journal ArticleDOI
TL;DR: In this paper, the authors describe the key to successful welding of duplex stainless steels, which differ from austenitic grades in some respects, and know-how combined with the use of appropriate welding procedures and consumables is therefore the key for successful welding.
Abstract: Duplex stainless steels have become important competitors to austenitic stainless steels in many applications and a great deal of attention has focused on the welding aspects. The introduction of modern grades with improved properties and a competitive price level have increased their use in the offshore, petrochemical and shipbuilding industries, for example. In particular the newer grades, with their higher nitrogen content and improved weldability, have moved duplex stainless steels from a position as “interesting” materials to one of “useful in practice”. However, duplex stainless steels differ from austenitic grades in some respects, and know‐how combined with the use of appropriate welding procedures and consumables is therefore the key to successful welding.

48 citations


Patent
10 Apr 1995
TL;DR: In this article, a flux-cored wire for gas shield arc welding used for fillet welding, that good plasma resistance, bead shape, outward appearance and detachability of slag are obtd.
Abstract: PROBLEM TO BE SOLVED: To provide a flux-cored wire for gas shield arc welding used for fillet welding, that good plasma resistance, bead shape, outward appearance and detachability of slag are obtd. even in the case of using the high speed horizontal fillet welding under high current welding condition, and a flux-cored wire for whole position welding, that the weldability in various weldings, is good including the metal dripping resistance in the vertical welding even in the case of using in the wide welding range containing the high current zone. SOLUTION: Relating to the flux-cored wire for gas shield arc welding constituted by filling the flux in a steel-made outer shell, an iron base Si-Mn alloy powder as the flux, consisting of, by weight, 0.40-1.20% C, 5-12% Si, 19-42% Mn and the balance Fe so as to satisfy Si >=11.89-2.92 C-0.077 Mn and having =1.0% based on the whole wt. of the wire, and further, 2.0-7.0% TiO2, 0.2-1.5% SiO2, 0.1-1.2% ZrO2 and 0.01-0.3% fluoride (converted into F) are contained.

47 citations


Journal ArticleDOI
TL;DR: In this paper, the authors proposed a method to determine the necessary preheat temperature through the charts describing the following respective effects: 1) steel composition; 2) diffusible hydrogen content of weld metal; 3) weld heat input; 4) wall thickness; 5) weld metal yield strength; 6) joint restraint.
Abstract: Preheating is carried out to avoid cold cracking in steel welding. The occurrence of cold cracking is considered to be governed by accumulating diffusible hydrogen, welding residual stresses and hardness at the crack initiation site. The hydrogen accumulating at the crack site depends on the initial diffusible hydrogen content in weld metal, the weld heat input and the wall thickness. The local residual stress is governed by the weld metal yield strength, the joint restraint and the notch stress concentration factor. The HAZ hardness is influenced by the steel chemical composition, the weld heat input and the plate (wall) thickness.These influential factors affect cold cracking independenly or in an interacted manner. It must be, thus, difficult to predict the necessary preheat temperature by a theoretical method or simple formulae. The method presently proposed is completely based on the empirical results by y-groove weld cracking tests. The present method determines the necessary preheat temperature through the charts describing the following respective effects : 1) steel composition ; 2) diffusible hydrogen content of weld metal ; 3) weld heat input ; 4) wall thickness ; 5) weld metal yield strength ; 6) joint restraint. As to the steel composition, this method uses CEN carbon equivalent that preferably assesses weldability of a wide variety of steels. Also, this method considers a logarithmic dependence of the weld metal hydrogen and the analysis of hydrogen diffusion in a weld has proved that the hydrogen effect on cold cracking must be logarithmic.

35 citations


Book
01 Dec 1995
TL;DR: In this article, the authors present a detailed overview of the mechanical and physical properties of steel castings and their application in various industrial applications, including the following: Industrial Applications Advantages Specifying Purchasing Policy Functional Considerations of Design Manufacturing Design Considerations Concurrent Engineering Engineering Drawings for Casting Production Redesign of Steel Castings Cast-Weld Construction Pattern Equipment Casting and Molding Processes Melting Finishing/Heat Treatment/Inspection Process Capability and Tolerences Quality Control and Quality Assurance Carbon and Low Alloy Steels for Pressure Containing and Struct
Abstract: This guide tells you what you need to know about mechanical and physical properties and other pertinent information in the design and use of steel castings. Contents include: Introduction Industrial Applications Advantages Specifying Purchasing Policy Functional Considerations of Design Manufacturing Design Considerations Concurrent Engineering Engineering Drawings for Casting Production Redesign of Steel Castings Cast-Weld Construction Pattern Equipment Casting and Molding Processes Melting Finishing/Heat Treatment/Inspection Process Capability and Tolerences Quality Control and Quality Assurance Carbon and Low Alloy Steels for Pressure Containing and Structural Parts, Wear Resistant Steels Corrosion-Resistant High Alloy Steels Nickel Base Coatings Heat Resistant High Alloy Steels Low Temperature and Cryogenic Steels Hardenability and Heat Treatment Weldability and Welding Machinability Physical Properties.

35 citations


Journal ArticleDOI
TL;DR: In this article, microhardness, aluminium content and phase constitution characteristics in the Fe-Al alloy layer of calorized steel pipe were investigated by optical microscopy, micro-hardness measurements, SEM, electron probe microanalysis, TEM and X-ray diffractometry, etc.
Abstract: Microhardness, aluminium content and phase constitution characteristics in the Fe-Al alloy layer of calorized steel pipe were investigated by optical microscopy, microhardness measurements, SEM, electron probe microanalysis, TEM and X-ray diffractometry, etc. Experimental results indicate that the Fe-Al alloy layer of calorized steel pipe was mainly composed of FeAl phase (2.0%–36% Al), Fe3Al phase (13.9%–20% Al) and α-Fe (Al) solid solution, and the microhardness in the Fe-Al alloy layer was 600-310 HM from the surface layer to the inside. There were no higher aluminium content phases, such as brittle FeAl2, Fe2Al5 and FeAl3. The ability to resist deformation and the weldability of the calorized steel pipe were remarkably improved.

31 citations


Patent
16 Jun 1995
TL;DR: In this paper, a process for producing a steel pipe excellent in corrosion resistance even in an atmosphere containing wet carbon dioxide and trace hydrogen sulfide and also excellent in weldability at a reduced cost and an enhanced productivity is described.
Abstract: A process for producing a steel pipe excellent in corrosion resistance even in an atmosphere containing wet carbon dioxide and trace hydrogen sulfide and also excellent in weldability at a reduced cost and an enhanced productivity. The process comprises heating to 1,050-1,300 °C a billet containing, on the weight basis, 0.01 to less than 1.2 % of Si, 0.02-3.0 % of Mn, 7.5-14.0 % of Cr, 0.5-0.005 % of Al, a reduced amount of each of C, N, P and S, at least one of Cu, Ni, Co, Mo and W, and the balance consisting of Fe and inevitable impurities and having an MC value of at least 0, finishing hot rolling in the austenitic single-phase temperature region, winding up the rolled steel as a hot coil with a thickness of 3.0-25.4 mm, cooling the coil to at least 500 °C in a cooling rate of at least 0.01 °C/sec to give a steel substantially comprising martensite, reheating the steel to a temperature in the range of from 550 °C to the Ac1 transformation point, holding at that temperature for at least 15 min, cooling to an ordinary temperature, cutting in a given width, and continuously shaping in a cylindrical form while conducting resistance welding of both ends of the strip into a pipe.

27 citations



Patent
07 Jun 1995
TL;DR: In this paper, a high strength steel composition comprising ferrite and martensite/banite phases, the ferrite phase having primarily vanadium and mobium carbide or carbonitride precipitates, is prepared by a first rolling above the austenite recrystallization temperature; a second rolling below the anstenite re-scaling temperature; and a third rolling between the Ar3 and Ar1 transformation points, and water cooling to below about 400° C.
Abstract: A high strength steel composition comprising ferrite and martensite/banite phases, the ferrite phase having primarily vanadium and mobium carbide or carbonitride precipitates, is prepared by a first rolling above the austenite recrystallization temperature; a second rolling below the anstenite recrystallization temperature; a third rolling between the Ar3 and Ar1 transformation points, and water cooling to below about 400° C.

22 citations


Patent
Takuya Hara1, Hitoshi Asahi1, Hiroshi Tamehiro1, Taro Muraki1, Akira Kawakami1 
27 Sep 1995
TL;DR: Martensitic stainless steel as discussed by the authors is a type of stainless steel that is excellent in weldability and SSC resistance and has a tempered martensitic structure which contains on the weight basis 0.005 - 0.035 % of C, at most 0.03 % of S, 1.0 - 3.0 % of Mo, 0.5 - 5.4 % of REM, the balance substantially comprising Fe.
Abstract: Martensitic stainless steel excellent in weldability and SSC resistance and having a tempered martensitic structure which contains on the weight basis 0.005 - 0.035 % of C, at most 0.50 % of Si, 0.1 - 1.0 % of Mn, at most 0.03 % of P, at most 0.005 % of S, 1.0 - 3.0 % of Mo, 1.0 - 4.0 % of Cu, 1.5 - 5.0 % of Ni, at most 0.06 % of Al, at most 0.01 % of N and such an amount of Cr as to satisfy the relationship that 13 > Cr + 1.6 Mo » 8, satisfies the relationship that C + N « 0.03 and 40C + 34N + Ni + 0.3Cu - 1.1Cr » -10, optionally contains further at least one element selected from among 0.05 - 0.1 % of Ti, 0.01 - 0.2 % of Zr, 0.001 - 0.02 % of Ca and 0.003 - 0.4 % of REM, the balance substantially comprising Fe. The process for producing the steel comprises hot rolling the billet of the same into a steel plate, austenizing the plate at a temperature in the range of the Ac3 point to 1,000 °C, followed by hardening, and subjecting to final tempering at a temperature in the range of 550 °C to the Ac1 point, followed by cold forming.

20 citations


Patent
09 Oct 1995
TL;DR: In this paper, a high-tensile Al-Cu base alloy has been proposed for welding structures having high strength, excellent in weldability and stress corrosion cracking resistance and furthermore excellent in workability.
Abstract: PROBLEM TO BE SOLVED: To produce an Al alloy for welding structures having high strength, excellent in weldability and stress corrosion cracking resistance and furthermore excellent in workability. SOLUTION: This high-tensile Al-Cu base alloy excellent in weldability has a compsn. contg., by weight, 2 to 8% Cu and 0.03 to 3.0% Sc, furthermore contg. at least one kind of 0.005 to 0.2% Ti and 0.0001 to 0.08% B, moreover contg. one or ≥ two kinds among 0.07 to 1.5% Si, 0.1 to 1.5% Fe, 0.2 to 2.0% Mg, 0.01 to 1.5% Mn, 0.01 to 0.6% Cr, 0.01 to 0.5% V, 0.05 to 3.0% Ni, 0.01 to 0.5% Mo, 0.03 to 1.0% Ag, 0.01 to 0.25% Zr and 0.03 to 5.0% rare earth elements (one or ≥ two kinds among La, Ce, Pr, Nd and Sm), and the balance aluminum with inevitable impurities. This alloy has about ≥400N/mm 2 tensile strength. COPYRIGHT: (C)1997,JPO

Patent
02 Jun 1995
TL;DR: In this article, a secondary battery is provided with a closed external can made of aluminum alloy containing manganese, and the resistance welding metal is joined to the surface of the external can by an impact process.
Abstract: PURPOSE: To provide a secondary battery having an aluminum external can in which crack formation can be prevented effectively at the time of welding, which can be made tough, and to which resistance welding metal can be welded easily, simply, and efficiently at low cost. CONSTITUTION: A secondary battery is provided with a closed external can 1 made of aluminum. The external can 1 is made of aluminum alloy containing manganese. Taking the strength, processibility, and weldability into consideration, the content of manganese in the aluminum alloy for the external can 1 is specified to be within a range not less than 0.5wt.% and not more than 2.5wt.%. The resistance welding metal 5 is press-joined to the surface of the external can 1 by an impact process. Consequently, as compared with a conventional external can, the can has both improved tensile strength and yield strength. Moreover, the resistance welding metal joined to the external can has extremely high strength and is effectively prevented from coming out of the external can. COPYRIGHT: (C)1996,JPO

Journal Article
TL;DR: In this article, the authors investigated the relationship between hardness and welding parameters, including preheat, interpass temperature and heat input, for the welding of a 690 MPa microalloy quench and tempered steel.
Abstract: Specifications for the welding of high-strength steels are generally intended to control hydrogen cracking and provide adequate weld zone toughness for resistance to fatigue cracking and shock loading. The specifications should also allow welding to be undertaken safely and profitably. The work described here was designed to identify the optimum match of welding parameters, notably preheat, interpass temperature and heat input, for the welding of a 690 MPa (100 ksi) microalloy quench and tempered steel. The paper covers investigations into two aspects of weldability: toughness and hardness. The first part involved shielded metal arc (SMA) butt joint welding of carefully designed plates at a range of preheat and interpass temperatures and heat input values, to identify welding procedures that give maximum HAZ and weld metal toughness. The second is a laboratory study of bead-on-plate submerged arc welds to clearly identify the relationship between hardness and welding parameters. The test procedure for the first investigation involved SMA welding at preheat and interpass (P and I) temperatures from -20°C to 220°C (-4° to 428°F) using heat input values of (approximately) 1.3, 2.9 and 4 kJ/mm (33, 74 and 102 KJ/in.) Charpy V-notch energy and fracture appearance transition curves were then generated with the Charpy notches being carefully located to give the lowest toughness values. Results showed that the minimum preheat and interpass temperature for control of weld metal hydrogen cracking was 60°C (140°F) and that low values of toughness in both weld and heat-affected zone consistently occurred in the weld root region. Low preheat techniques and one-sided welding should therefore be avoided for critical applications. For weld metal, greatest toughness occurred at high preheat and interpass temperatures (160°C; 320°F) combined with low welding heat input (1.2 kJ/mm; 30 KJ/in). For high heat input welding, preheat and interpass temperature had little influence on toughness over the range of temperatures examined. For heat-affected zone regions, levels of toughness obtained when using the high preheat/low heat input and low preheat/high heat input techniques were similar. It was found, however, that careful control of preheat and interpass temperature was essential, for each heat input value, because toughness can drop off rapidly on either side of the optimum interpass temperature. For some applications, optimum preheat and interpass temperatures were found to lie between 60° and 90°C (140° and 194°F). In the second study, a series of bead-on-plate submerged arc welds was deposited using a wide range of preheat and interpass temperatures, voltages, currents and travel speeds. In each case, the welding parameters were chosen so that the welding power input (V x I) could be held constant while varying heat input, or vice versa. For each weld, hardness readings were taken in both the weld deposit and HAZ at approximately 1 mm (0.04 in.) from the weld interface. It was found that: 1) HAZ hardness readings (390-430 HV 30 for heat input values up to 2 kJ/mm) were consistently higher than weld metal hardness readings. 2) Heat input has a marginal effect on HAZ hardness up to about 2 kJ/mm (51 kJ/in.), however, above 2 kJ/mm the hardness drops off at a rate of approximately HV 30 for each increase of 1 kJ/mm (25 kJ/in.). 3) Weld metal hardness dropped continuously over the range of 0.5 to 4.5 kJ/mm (13 to 114 kJ/in.). 4) Both HAZ and weld metal hardness drops approximately 1 HV 30 for every 4°C (7.2°F) increase in preheat and interpass temperature. The results of this work have been used to develop an optimized weld design for butt joint welding of 35-50 mm (1.4-2 in.) plate. This uses high heat input for all but the weld capping passes, where high interpass temperatures and low heat input techniques are employed.

Patent
16 Jun 1995
TL;DR: A high-strength, fine-grained, low-medium carbon steel alloy provides both the physical and chemical properties to meet AAR specifications for cast railcar components, which steel alloy has improved weldability, higher impact strength and notch toughness for such rail car components.
Abstract: A high-strength, fine-grained, low-medium carbon steel alloy provides both the physical and chemical properties to meet AAR specifications for cast railcar components, which steel alloy has improved weldability, higher impact strength and notch toughness for such railcar components

Journal Article
TL;DR: In this paper, the postweld heat treatment (PWHT) procedures for 1 7-4 PH stainless steel weldments of matching chemistry was optimized vis-a-vis its microstructure prior to welding based on microstructural studies and room-temperature mechanical properties.
Abstract: The postweld heat treatment (PWHT) procedures for 1 7-4 PH stainless steel weldments of matching chemistry was optimized vis-a-vis its microstructure prior to welding based on microstructural studies and room-temperature mechanical properties. The 17-4 PH stainless steel was welded in two different prior microstructural conditions (condition A and condition H 1150) and then postweld heat treated to condition H900 or condition H1150, using different heat treatment procedures. Microstructural investigations and roomtemperature tensile properties were determined to study the combined effects of prior microstructural and PWHT procedures.

Journal ArticleDOI
TL;DR: In this paper, the effect of grain growth and as welded microstructure on notch toughness of both welded and PWHT welds is analyzed. And the main reason of toughness deterioration in the weld area is the M-A constituent present in that structure.
Abstract: Modern steels like TMCP or HSLA steels are excellent structural material for many engineering applications. Exploitation of physical strengthening mechanisms enables lowering of carbon and alloying element's content and improves weldability remarkably. On the other hand demands for higher welding efficiency requires higher and higher heat inputs which, in turn, favours softer transformation products like upper or granular bainite in the weld HAZ. Grain growth and the M-A constituent present in that structure are the main reason of toughness deterioration in the weld area. Paper brings an analysis of the effect of grain growth and as welded microstructure on notch toughness of as welded and PWHT welds.

Patent
05 Sep 1995
TL;DR: In this paper, the componental compsn. is specified and the weld cracking sensitivity index and carbon equivalent value are prescribed to produce a high tensile strength steel excellent in SR cracking resistance or the like.
Abstract: PURPOSE:To produce a high tensile strength steel excellent in SR cracking resistance or the like by preparing a high tensile strength steel in which the componental compsn. is specified and the weld cracking sensitivity index and carbon equivalent value are prescribed. CONSTITUTION:A high tensile strength steel having a compsn. contg., by weight, 0.075 to 0.094% C, 0.01 to 0.4% Si, 0.5 to 1.5% Mn, =0.45, and the balance iron with inevitable impurities and substantially contg. no B is prepd. Thus, the 780N/mm class high tensile strength steel excellent in weldability, acoustic anisotropy and SR cracking properties can be obtd.

01 Sep 1995
TL;DR: B2-phase FeAl ordered intermetallic alloys based on an Fe-36 at.% Al composition are being developed to optimize a combination of properties that includes high-temperature strength, room-time ductility, and weldability as mentioned in this paper.
Abstract: B2-phase FeAl ordered intermetallic alloys based on an Fe-36 at.% Al composition are being developed to optimize a combination of properties that includes high-temperature strength, room-temperature ductility, and weldability. Microalloying with boron and proper processing are very important for FeAl properties optimization. These alloys also have the good to outstanding resistance to oxidation, sulfidation, and corrosion in molten salts or chlorides at elevated temperatures, characteristic of FeAl with 30--40 at.% Al. Ingot- and powder-metallurgy (IM and PM, respectively) processing both produce good properties, including strength above 400 MPa up to about 750 C. Technology development to produce FeAl components for industry testing is in progress. In parallel, weld-overlay cladding and powder coating technologies are also being developed to take immediate advantage of the high-temperature corrosion/oxidation and erosion/wear resistance of FeAl.

01 Apr 1995
TL;DR: In this article, the authors present a discussion of various aspects of cracking tests, including practical aspects, interpretation, standardization and suggestions for future development, and provide a background for developing research programs on controlling hydrogen cracking in higher strength materials.
Abstract: Tests for hydrogen cracking in welding have been used for many years in research and steel development and in recent years are playing an increasing role in material procurement. A multitude of different tests have been proposed, many being developed for a specific research program and not being used again. Where tests are being used by several laboratories, lack of standardization frustrates the comparison of results among laboratories and is a serious limitation when the test is used for procurement purposes. There is a trend to higher strength steels in the energy sector and the control of potential cracking problems is a challenge that must be addressed if these materials are to be utilized successfully. Existing cracking tests will play an important role, and doubtless new tests will be introduced to tackle specific problems as they are identified. To provide a background for developing research programs on controlling hydrogen cracking in higher strength materials, this report presents a discussion of various aspects of cracking tests. No attempt is made to review available tests. Following background introduction of cracking tests in general, this report addresses practical aspects, interpretation, standardization and suggestions for future development.

Journal ArticleDOI
TL;DR: In this article, an investigation of the effect of tungsten on the HAZ properties of duplex stainless steel in a program to develop highly pitting corrosion resistant duplex steel was described.
Abstract: Summary This paper describes an investigation of the effect of tungsten on the HAZ properties of duplex stainless steel in a programme to develop highly pitting corrosion resistant duplex stainless steel The steels tested were modified SUS329J4L duplex stainless steel containing added tungsten The welded joints produced by gas tungsten arc (GTA or TIG) welding and the simulated HAZ were evaluated in terms of the pitting corrosion resistance, impact toughness, and microstructure, including an analysis of precipitates The results suggest that tungsten added up to 2 mass% is effective for improvement of the pitting corrosion resistance without heavy loss of impact toughness in the HAZ Tungsten addition exceeding 3 mass%, however, decreases both the HAZ impact toughness and pitting corrosion resistance by accelerating the precipitation of intermetallic compounds during the welding thermal cycles It is thus demonstrated that the pitting corrosion resistance in the HAZ of duplex stainless steel is improved

Journal ArticleDOI
TL;DR: In this paper, the results of hot dutility tests were conducted on FA-129 to determine the effect of test temperature, grain size, and atmosphere on the ductility.
Abstract: Significant interest exists in developing polycrystalline, long-range ordered iron-aluminide alloys for high temperature applications because of their unique properties such as superior oxidation resistance. However, detrimental properties such as low room temperature ductility and poor weldability restrict the use of iron-aluminides in structural applications. This paper describes the results of hot dutility tests conducted on iron-aluminide alloy FA-129 to determine the effect of test temperature, grain size and atmosphere on the ductility. Also, a preliminary study was performed to determine the hydrogen cold cracking sensitivity of weldments produced in varying atmospheres of water vapor.

Journal ArticleDOI
TL;DR: In this paper, a large diameter high strength sour service line pipe steel produced by employing the thermo-mechanical control process, i.e., controlled rolling followed by accelerated cooling, was examined for the susceptibility to hydrogen induced cracking under applied stress.
Abstract: The susceptibility to hydrogen induced cracking under applied stress was examined for a large diameter high strength sour service line pipe steel produced by employing the thermo-mechanical control process, i.e. controlled rolling followed by accelerated cooling. The low carbon content aimed at high toughness and weldability resulted in softening in the grain-refined and inter-critical heat-affected zone by thermal cycles of longitudinal sub-merged arc welding. The cracking susceptibility of weldment was transversely evaluated by TM0177-90 method A and compared with the parent metal.The parent metal indicated high resistance to cracking. Nonethelss, the weldment indicated the decrease in threshold stress, since the weldment ruptured preferably along the softened heat-affected zone. The cracking morphology in the softened heat-affected zone was recognized as stress oriented hydrogen induced cracking. Also performed was a large scale test to reveal the internal incipient cracks in the softened heat-affected zone. The observation confirmed that the initiation site was a small cluster of non-metallic inclusions which had probably no adverse effect on the resistance of the parent metal. He stress analysis of the weldment proved that the tension through thickness was generated at mid-thickness under the deformation constraint from surrounding harder parts. The enhanced tri-axiality of stress in company with the through thickness tension facilitates the onset of cracking caused by the hydrogen pressure mechanism. The crack morphology was consistently associated with the stress distribution.

Patent
15 Mar 1995
TL;DR: In this paper, a coated electrode for the high-Mo austenitic stainless steel, the coating flux containing 30-60% metallic carbonate, 15-30% metallic fluoride, and 15-20% metallic oxide is applied on the core having the composition consisthg of 0.001-0.05% Al, and 0.1-5% Co as required.
Abstract: PURPOSE: To provide a coated electrode which is appropriate for welding the high-Mo stainless steel to be used in a structure resistant for sea water and sea salt grain, and excellent in the corrosion resistance, the mechanical properties and the weldability of the weld metal. CONSTITUTION: In a coated electrode for the high-Mo austenitic stainless steel, the coating flux containing 30-60% metallic carbonate, 15-30% metallic fluoride, and 15-20% metallic oxide is applied on the core having the composition consisthg of 0.001-0.01% C, 0.01-0.2% Si, 0.01-2% Mn, 18-25% Cr, 55-75% Ni, 0.1-3% Cu, 0.1-0.3% N, 6-12% one or two kinds of Mo and W, 0.001-0.05% Al, and 0.1-5% Co as required.

Patent
14 Feb 1995
TL;DR: In this paper, the surface of the main body of a copper-base member constituted of copper or a copper alloy is applied with an Sn plating layer having 0.05 to 5.00μm thickness.
Abstract: PURPOSE: To produce a copper or copper alloy member improved in laser weldability. CONSTITUTION: This copper or copper alloy member excellent in layer weldability is the one in which the surface of the main body 1 of a copper-base member constituted of copper or a copper alloy is applied with an Sn plating layer 2 having 0.05 to 5.00μm thickness. Thus, the welding joint part free from defects in the joint part and excellent in mechanical properties can be obtd.

Patent
31 Jul 1995
TL;DR: In this paper, an ultra-high tensile strength steel whose microstructure is composed of a two phase mixed one of martensite-bainite and ferrite is presented.
Abstract: PROBLEM TO BE SOLVED: To produce an ultra-high tensile strength steel excellent in low temp toughness and spot weldability by subjecting a low carbon-low alloy steel having a specified compsn to tempering treatment under specified temp conditions SOLUTION: A steel having a compsn contg, by weight, 005 to 010% C, = two kinds among 01 to 10% Ni, 01 to 12% Cu, 01 to 08% Cr and 0001 to 0005% Ca, in which the value of P defined by the formula is regulated to 19 to 28 or moreover contg small amounts of one or >= two kinds among Ce, Mg and Y is tempered within the temp of 400 degC to the AC1 point The ultra-high tensile strength steel whose microstructure is composed of a two phase mixed one of martensite-bainite and ferrite by 20 to 90% in a fractional ratio, excellent in a balance of strength and low temp toughness, excellent in spot weldability and having >=950MPa tensile strength can be produced

Journal Article
TL;DR: In this paper, a sequence of pulsed and continuous wave (CW) CO 2 laser beam welds was made on 1.7 mm (0.067-in.) thick coupons of Ti-14.3.
Abstract: The CO 2 laser beam weldability of Ti-14.3.wt-%-Al-21 wt-% Nb, a Ti 3 Al-Nb (alpha 2 aluminide) alloy, was investigated. A sequence of pulsed and continuous wave (CW) CO 2 laser beam welds was made on 1.7 mm (0.067-in.) thick coupons of Ti-1421. The weld cross-sections were subjected to microhardness evaluation and characterized by optical metallography. The hardness values were plotted with respect to calculated cooling rates to reveal possible trends in microhardness. Laser welds were produced without cracks, porosity or other discontinuities. Laser welding with calculated cooling rates between 195° and 10, 400°C/s produced relatively constant microhardness values. These values ranged between 373 and 432 DPH for the heat-affected zone (HAZ), and between 364 and 416 for the fusion zone (FZ). These results are in contrast to Mascorella's results for gas tungsten arc welding, which showed microhardness values have an increasing trend with increased cooling rate (from 297 to 488 HAZ and from 292 to 459 FZ for coolings rates from 2 to 50°C/s). Bend ductility values within the unaffected base metal (UBM) range were obtained in full penetration longitudinal bend specimens for laser welds with calculated cooling rates above 3400°C/s. For cooling rates of 1380°C/s and lower ductilities were well below the UBM range. The slower cooled welds exhibited a larger flat cleavage fracture area and lower ductility than the rapidly cooled welds. The results of this investigation show that careful selection of CO 2 laser welding conditions will result in cooling rates that will yield more ductile HAZs and FZs when compared to gas tungsten arc welding (GTAW)


Patent
21 Sep 1995
TL;DR: In this article, a low C and Cr type steel for stack and flue for natural gas firing has been proposed, which has a composition consisting of, by weight, = 2 kinds among Al, Nb, and V and satisfying Pcm < 0.28, where Pcm is represented by Pcm=C+Mn/20+Cr/20.
Abstract: PURPOSE: To produce a steel for stack and flue for natural gas firing, more inexpensive than stainless steel, as low C and Cr type steel, and having pitting corrosion resistance two or more times that of rolled steel for welded structure. CONSTITUTION: This steel for stack and flue for natural gas firing has a composition consisting of, by weight, =2 kinds among Al, Nb, and V and satisfying Pcm<=0.28, where Pcm is represented by Pcm=C+Mn/20+Cr/20. The steel has superior weldability and gas cutting property.

Patent
18 Jul 1995
TL;DR: A process for producing steel material and steel pipe excellent in corrosion resistance in an environment containing wet carbon dioxide and trace hydrogen sulfide and also excellent in weldability at a low cost and a high productivity is described in this paper.
Abstract: A process for producing steel material and steel pipe excellent in corrosion resistance in an environment containing wet carbon dioxide and trace hydrogen sulfide and also excellent in weldability at a low cost and a high productivity. The process comprises heating to 1,100 - 1,300 °C a billet containing, on the weight basis, 0.01 - 0.6 % of Si, 0.02 - 1.8 % of Mn, 7.5 - 14.0 % of Cr, 1.5 - 4.0 % of Cu, 0.005 - 0.1 % of Al, at most 0.02 % of C, at most 0.02 % of N, at most 0.025 % of P, at least 0.01 % of S, and the balance consisting of Fe and inevitable impurities, and hot rolling the heated billet under such conditions that the cumulative draft is at least 65 % at temperatures below 1,050 °C and the rolling termination temperature is 800 °C or above, followed by cooling at a cooling rate of less than 0.02 °C/min at least to a temperature of 500 °C to render the metal structure substantially ferritic.

Patent
08 Mar 1995
TL;DR: In this paper, the authors proposed a ferritic stainless steel with a composition consisting of, by weight, ≤ 0.05% C, ≤ 1.5% Si, ≤ 2.0% Ti, > 0.
Abstract: PURPOSE: To inexpensively produce a ferritic stainless steel excellent in corrosion resistance and weldability. CONSTITUTION: This ferritic stainless steel excellent in corrosion resistance and weldability has a composition consisting of, by weight, ≤0.05% C, ≤1.5% Si, ≤2.0% Mn, 11-30% Cr, 0.1-1.0% Ti, >0.2-0.7% Nb, 0.005-0.5% Al, ≤0.05% N, ≤0.05% P, ≤0.005% O, >0.001-0.03% S, and the balance Fe with inevitable impurities or further containing 0.0003-0.05% Mg and further containing, if necessary, ≤3.0% Cu, Ni, and Mo. COPYRIGHT: (C)1996,JPO