Weldasearch - Sample Abstracts

Weldability of structural steel plates

248148
Characterising phase transformations of different LTT [low transformation temperature] alloys and their effect on residual stresses and cold cracking.
KROMM A; KANNENGIESSER T; INTERNATIONAL INSTITUTE OF WELDING
Welding in the World, vol.55, no.3-4. Mar.-Apr.2011. pp.48-56. 13 fig., 8 tab., 20 ref.
[in English]
(Doc.IIW-2060; Commission IX)

Phase transformation behaviour and residual stress development during welding using low transformation temperature (LTT) alloys as filler wire were studied by in situ high-energy (max. 150 keV) synchrotron diffraction, single-sensor differential thermal analysis and residual stress analysis. The LTT alloys investigated contained 0.04-0.11%C, 0.7-1.01%Mn, 7.59-10%Cr, 5.89-12%Ni. The parent metal was S690 steel (0.116%C, 1.52%Mn, 0.498%Cr, 0.481%Ni, 0.111%Mo, 0.054%V) which was pre-welded by the MMA process using the filler metals under test, and then the weld metal was remelted by TIG welding during the diffraction experiment. Microstructural transformation was investigated by the SS-DTA technique and by diffraction experiments during heating and cooling. Residual stresses associated with the martensite and austenite phases were determined across the weld. Cold cracking behaviour during MMA welding of preheated 10 mm S690 plate was assessed by the Tekken test combined with micrography, hardness testing and measurement of cracks.

248611
Development of 590N/mm2 steel with good weldability for building structures.
WATANABE Y; YOSHII K; YOSHIDA Y; ISHIBASHI K; INOUE H
Nippon Steel Technical Report, no.90. July 2004. pp.53-58. 4 fig., 7 tab., 8 ref.
[in English]

Steel of grade BT-HT440 (0.06-0.08%C, 1.40-1.47%Mn) for building structures was developed with the aim of enable welding at low preheating temperature or without preheating. The development of the steel to obtain low susceptibility to weld cracking due to a boron-free, 0.06-0.08%C composition in combination with precipitation hardening with Cu and other alloying elements is discussed. Weldability was investigated using MMA or MIG welding of plates 45-50 mm thickness and preheat temperatures of 6-50 deg.C. HAZ hardness was determined. Properties of column welded joints using submerged arc or GMA welding and plates thickness 50 mm or electroslag welding of plates thickness 50-100 mm were determined including hardness, tensile and impact properties and weld cracking susceptibility of different regions. The results for the different welding methods are compared.

247628
Material design and weldability of high strength seamless pipe.
HIRATA H; HAMADA M; ARAI Y; KONDO K; HISAMUNE N; HITOSHIO K; MURASE T
In: ISOPE-2009. Proceedings, 19th International Offshore and Polar Engineering Conference, Osaka, Japan, 21-26 July 2009. Ed: J.S.Chung, S.Prinsenberg, S.W.Hong and S.Nagata. Publ: Cupertino, CA 95015-0189, USA; ISOPE (International Society of Offshore and Polar Engineers); 2009. Vol.4. The Third (2009) ISOPE Strain-Based Design Symposium - ISOPE SBD-2009. Material Development. pp.67-72. 12 fig., 5 tab., 10 ref.
[in English]
[CD ROM; 2009-TPC-657.pdf][See also Weldasearch 236459]

In relation to the development of pipelines for oil and gas fields in ultra-deep water, an investigation is presented into the effect of material chemical composition on hardening and softening in the HAZ and the use of circumferential weldability tests to verify the material design. The test materials comprised microalloyed steel plates (thickness 20 or 30 mm) containing 0.01-0.09%C with Pcm of 0.10-0.21%, obtained by altering Mn, Cr and Mo content, prepared by rolling, quenching and tempering. The effect of composition on weldability was evaluated by using taper-type maximum hardness tests. Circumferential welding tests were conducted on X80 and X90 grade production pipes with optimised compositions (0.04%C, 2.1%Mn, 0.74%Mo, Si, Cr, Al, Ca; Pcm 0.22). U-type butt welding was performed by multirun TIG welding using wire equivalent to AWS 5.28 ER100S-G for the root and first few runs and submerged arc welding using filler equivalent to AWS 5.23 F10A2-EG-G and a bond type flux for the rest. Welded joint mechanical properties were characterised by Vickers hardness distribution measurements as well as tensile and Charpy impact tests. The relationships between carbon content, Pcm, hardness and microstructure are discussed.

247599
Risk of cold cracking in welding of structural high-strength steels.
MAKHNENKO V I; POZNYAKOV V D; VELIKOIVANENKO E A; MAKHNENKO O V; ROZYNKA G F; PIVTORAK N I
Paton Welding Journal, no.12. Dec.2009. pp.2-6. 10 fig., 2 tab., 3 ref.
[in English; Russian]
(Translated from Avtomaticheskaya Svarka)

A mathematical model defining the risk of cold cracking when welding low-alloy high-strength structural steels was developed. The model takes account of the detailed distribution of microstructural phases, diffusible hydrogen content and stress within the weld zone and is based upon a Weibull probability model of brittle fracture. Data for the model were derived from tests and measurements made on a root butt weld in a V butt preparation in 18 mm thickness 14KhG2SAFD steel (0.13%C, 1.42%Mn, 0.44%Cr, 0.39%Cu) with ANP-10 electrode (0.09%C, 1.9%Mn). Initial temperature, filler metal hydrogen content and test piece restraint width were experimental variables.

246931
Weldability of high yield strength thermomechanical steel (Spawalnosc stali obrabianej termomechanicznie ...).
GORKA J
Biuletyn Instytutu Spawalnictwa, vol.54, no.5. 2010. pp.165-169. 14 fig., 7 tab., 9 ref.
[in Polish]

Weldability of steel S700MC (0.12%C, 0.60%Si, 2.10%Mn, 0.50%Mo, 0.20%V, 0.09%Nb, 0.22%Ti, 0.015%Al, 0.015%S, 0.025%P) was investigated. Butt joints in plates of thickness 10 mm were MAG welded in six runs using wire Mn4Ni1.5CrMo (0.09%C, 0.52%Si, 1.68%Mn, 0.21%Cr, 1.50%Ni, 0.50%Mo, 0.012%S, 0.005%P) of diameter 1.0 mm. Macrostructural investigations, chemical analysis and hardness measurements in the HAZ, parent material and in the weld zone were performed. A comparison between TMCP process, TMCP + ACC, TMCP + DIC and conventional rolling is made. Results are presented and discussed.

246928
Weldability of high-strength steels in repair work of structures after long-lasting service life (Spawalnosc stali wysokowytrzymalych ...).
POZNJAKOW W D
Biuletyn Instytutu Spawalnictwa, vol.54, no.5. 2010. pp.136-138, 141-144. 12 fig., 2 tab., 3 ref.
[in Polish]

The influence of the state of stress in material on the initiation of cold cracks was investigated by mathematical calculations and experiment. Steel 14ChG2SAFD (0.13%C, 0.57%Si, 1.42%Mn, 0.44%Cr, 0.39%Cu, 0.08%V, 0.08%Al, 0.015%S, 0.019%P) of up to 40 mm in thickness was tested. Welding was done using covered electrode ANP-10 (0.09%C, 0.43%Si, 1.9%Mn, 0.01%V, 0.02%S and 0.02%P). Mechanical properties of welds made using filler wire Sv-10ChN2GSMFTJu and Ar-22%CO2 in 20 mm plate of steel 17Ch2M (17X2M: 0.19%C, 0.2%Si, 0.6%Mn, 1.55%Cr, 0.3%Mo, 0.006%Si, 0.014%P) were tested also. The probability of cold crack formation as a function of hydrogen content, preheating of the material, martensite content in weld metal and HAZ, and different fixing positions was estimated. On the basis of mathematical modelling of temperature distribution, amount of hydrogen diffusion, microstructural changes, state of stress and strain in the weld zone, the basis for the evaluation of welding technologies was formulated to improve the quality and reliability of repaired structures due to decreased level of internal stresses.

240020
Heat treatment procedures for hydrogen assisted cold cracking avoidance in S 1100 QL steel root welds.
WONGPANYA P; BOELLINGHAUS T; LOTHONGKUM G; INTERNATIONAL INSTITUTE OF WELDING
Welding in the World, vol.52, Special Issue. 2008. Session: D - Hydrogen Induced Cracking. pp.671-678. 14 fig., 2 tab., 18 ref.
[in English]
[A CD-ROM is available also: Paper no.40449] (Also published in Proceedings, Safety and Reliability of Welded Components in Energy and Processing Industry, IIW International Conference, Graz, Austria, 10-11 July 2008. Publ: A-8010, Graz, Austria; Technische Universitat Graz; 2008. ISBN 978-3-85125-019-0)[Similar paper: Welding in the World, vol.52, no.3-4. Mar.-Apr.2008. pp.79-92; Weldasearch 233282]

A thermal and structural finite element analyses of a five layered welded S1100QL 12 mm plate is compared to experimental MIG/MAG welded data from Instrumented Restraint Cracking (IRC) test plates and presented to determine the influence of inhomogeneous hydrogen removal heat treatment (HRHT) procedures on the residual stresses in multi-pass welds. These HRHT procedures include: preheating up to 250 deg.C and postheating at various temperatures (50-250 deg.C) for various holding times (30-240 mins). The weight percent compositions of the parent and undermatching filler material are respectively: S 1100 (0.17%C, 0.27%Si, 0.85%Mn, 0.46%Cr, 1.88%Ni, 0.45%Mo) and Union X96 (0.12%C, 0.78%Si, 1.86%Mn, 0.46%Cr, 2.36%Ni, 0.53%Mo). Effects of heat treatment and initial hydrogen content in the weld metal on crack length, effect of preheat temperature on strain along the crack path, effect on residual stresses of preheat temperature and restraint levels, and effects of postheating conditions on hydrogen concentration and crack length were investigated, mainly by numerical modelling methods.

236827
Investigation on hydrogen-induced cracking susceptibility of HG980D steel with yield strength 900 MPa.
GAO Y J; WANG C; XU Z L
China Welding, vol.17, no.3. Sept.2008. pp.15-19. 3 fig., 5 tab., 3 ref.
[in English]

Welding was carried out on HG980D steel (0.096%C, 0.3%Si, 1.43%Mn, 0.61%Ni, 0.48%Cr, 0.41%Mo, 0.053%V) plates of thickness 25 mm using filler material containing different levels of diffusible hydrogen; the effect of the hydrogen on the implant critical fracture strength and on the fracture modes for hydrogen induced cracking were examined. The microstructure and hardness in the HAZ at different cooling times were also studied. Fractography was used to determine the fracture modes (quasicleavage, microvoid coalescence) at the different hydrogen levels.

234717
Development of thick steel plates for shipbuilding having high strength and good weldability.
KIM S H; SUH I S; KANG K B
In: ISOPE 2007. Offshore and Polar Engineering. Proceedings, 17th International Conference, Lisbon, Portugal, 1-6 July 2007. Ed: J.S.Chung, S.W.Hong, S.Nagata, J.N.A.Antonio and W.Koterayama. Publ: Cupertino, CA 95015-0189, USA; ISOPE (International Society of Offshore and Polar Engineers); 2007. Vol.4. The First (2007) ISOPE Strain-Based Design Symposium. High-Performance Materials. Advanced Steel and Structures. pp.3313-3317. 11 fig., 4 tab., 7 ref.
[in English]
[CD ROM]

Heavy gauge EH36 and EH40 grade steel plates were developed for large container shipbuilding under controlled chemical composition, plate rolling and accelerated cooling conditions, and their mechanical properties and weldability were investigated. Alloy design incorporated boron addition to improve hardenability and optimised thermomechanical control processing variables to enhance mechanical properties and to reduce inhomogeneity in the thickness direction. EH36 was based on low levels of C, Si and Mn and microalloyed with Ti and Nb. EH40 also contained a little boron. Parent materials were characterised with respect to microstructure, hardness, tensile properties and impact toughness. Welding was performed in butt joints for plate of 85 mm in thickness by an electro-gas process in the 3G (vertical up) position using CO2 shielding gas. Weldability was assessed by oblique Y-groove method evaluations of weld cracking sensitivity using AWS A5.29 81T1-K2 filler.

227293
Developments in hot-rolled high-strength structural steels.
PORTER D
Hitsaustekniikka, vol.56, no.5. 2006. Special Issue: Nordic Welding Conference and Expo 2006, Tampere, Finland, 8-9 Nov.2006. pp.33-39. 9 fig., 6 tab.
[in English]

An overview is presented of the microstructure and mechanical properties of hot-rolled high-strength structural steels obtained from the hot strip mill and the plate mill of Ruukki Production steelworks at Raahe, Finland. The grades discussed include the martensitic steels Optim 900QC (0.01%C, 0.03%Si, 1.15%Mn) and 960QC (0.01%C, 0.02%Si, 1.2%Mn), and the low alloy steels PC F500W (0.04%C, 0.55%Si, 2.15%Mn, 0.25%Cr, 1%Ni, 0.3%Cu, 0.25%Mo) and S700ML (0.05%C, 1.5%Mn, 1.5%Cr, 1%Ni, 0.5%Cu, 0.5%Mo). Structural and mechanical characteristics are reviewed such as roll forming capability, tensile strength, yield strength, impact toughness, hot-dip galvanising properties, elongation, hardness and weldability. Quenched plate mill products are also outlined.

225464
Advanced steel plates excellent in weldability.
TANAKA Y
Welding Technology, vol.53, no.4. Apr.2005. Special Issue: Welding of Thick Plate. pp.80-86. 7 fig., 3 tab., 15 ref.
[in Japanese]

The manufacture of advanced steel plate with improved weldability by the TMCP (Thermo-Mechanical Control Process) method is discussed. The metallurgical principles of TMCP technology are introduced; the method uses minimum alloying additions and precise temperature control to improve the strength, toughness and weldability. Yield strength, tensile strength and grain structure of TMCP steel, normalised steel and ordinal-rolled steel were compared. The joint strength and HAZ softening behaviour of TMCP were examined. In the case of high-heat input welding, the HAZ toughness can be improved by controlled crystalline structure of the parent material. Hardness distribution across a submerged arc welded joint was determined. By application of DQT (direct-quenched and tempered) technology, the steel grade HT780 (0.05%C, 1.34%Mn, 1.05%Cu, 0.94%Ni, Mo, Nb, V or 0.06%C, 1.34%Mn, 0.97%Cu, 1.03%Ni, Cr, Mo, Nb, V) was developed with a low crack sensitivity indicator. Incidence of root cracking as a function of preheat temperature was determined for HT780 when welded using E1106-G electrodes. Characteristics of structural steels containing TiN and effects of sulphur on weldability are briefly discussed.

224927
Finite element modelling: a solution to seam end cracking?
McPHERSON N A; McGIBBON K; WEN S W
Science and Technology of Welding and Joining, vol.11, no.2. Mar.2006. pp.191-199. 16 fig., 4 tab., 11 ref.
[in English]
[On-line Journal: http://www.ingentaconnect.com/content/maney/stwj]

The susceptibility of the single-sided submerged arc welding (SAW) process to seam end cracking is described and the characteristics of the seam end crack are outlined. A formula to predict cracking susceptibility based on weld metal composition is presented. The stress and strain (deformation) response of the weld near the crack site during welding and cooling was modelled using a finite element method. The plate seam welding process modelled was a single-wire single-pass SAW process, using a slot run-off plate configuration, and the material was DH36 steel (Fe 0.15%C, 0.38%Si, 1.3%Mn, 0.012%P, 0.01%S, 0.018%Cr, 0.005%Mo, 0.04%Ni, 0.025%Al, 0.023%Cu, 0.006%N, 0.025%Nb). Weld global distortion, weld transverse deformation and transverse stress evolution near the crack site were analysed.

224246
Development of high-performance steel plates with excellent weldability.
KANG K B
In: Proceedings, ISOPE-2005, 15th International Offshore and Polar Engineering Conference, Seoul, Korea, 19-24 June 2005. Ed: R.Ayer, T.Yao, J.S.Chung, H.G.Wheat and N.Kato. Publ: Cupertino, CA 95015-0189, USA; ISOPE (International Society of Offshore and Polar Engineers); 2005. ISBN 1-880653-64-8. Vol.4. ISOPE Third (2005) High Performance Materials Symposium: Advanced Welding. Welding. pp.81-89. 19 fig., 13 tab., 5 ref.
[in English]
[CD ROM]

In relation to shipbuilding, offshore structure and pipeline applications, the welding performances of representative plate products are presented and a technology for enhancing the HAZ toughness for high heat input welding by improving the thermal stability of TiN precipitates through abnormal austenite grain growth suppression is described. The examples discussed are an EH-36 grade plate (0.07%C, 0.15%Si, 1.55%Mn) for high heat input tandem electro-gas welding, API-2W Gr. 50 and 60 plates (0.08%C, 0.25%Si, 1.45%Mn and 0.08%C, 0.15%Si, 1.58%Mn, respectively) welded by multi-run submerged arc welding (SAW), API-X80 grade plates (0.07%C, 0.33%Si, 1.78%Mn) welded by two-pole SAW, and X80 plate girth welding by FCA. Welded joints were characterised by tensile, Charpy impact and CTOD tests.

220932
High performance steel plates for tank and pressure vessel use - high strength steel plates with excellent weldability and superior toughness for the energy industry.
HAYASHI K; ARAKI K; ABE T
JFE Technical Report, no.5. Mar.2005. Special Issue: Steel Plates. pp.66-73. 12 fig., 15 tab., 7 ref.
[in English]
(Originally published in JFE Giho, no.5. Aug.2004. pp.56-62)

The properties of a series of high performance 610 MPa class HSLA (high strength low alloy) plate steels are discussed and the manufacturing technology for heavy section steel plates by a combined forging/plate rolling process is described. The steels considered included: JFE-HITEN610U2 (thickness 38-75 mm, 0.08%C, 1.34-1.44%Mn with Mo, V additions) for tanks/penstocks; JFE-HITEN610U2L (thickness 50 mm, 0.07%C, 1.32%Mn with Cu, Ni, Cr, Mo, V additions) for low-temperature tanks; JFE-HITEN610E (thickness 22-45 mm, 0.09%C, 1,37%Mn with Mo, V additions) for oil storage tanks; and JIS G 3120 SQV2B (thickness 120 mm, 0.17%C, 1.44%Mn, 0.13%Cr, 0.66%Ni, 0.55%Mo) for use in nuclear reactors. Mechanical properties of parent steels and of 610U2 submerged arc, 610U2L shielded metal arc (MMA) and 610E electrogas arc welded joints are reported.

220931
High performance steel plates for construction and industrial machinery use - new steel plates for construction and industrial machinery use with high strength and superior toughness combined with good weldability and formability.
MUROTA Y; ABE T; HASHIMOTO M
JFE Technical Report, no.5. Mar.2005. Special Issue: Steel Plates. pp.60-65. 10 fig., 6 tab., 6 ref.
[in English]
(Originally published in JFE Giho, no.5. Aug.2004. pp.51-55)

The target properties and performance are discussed for various steel plates (thickness 6-32 mm) namely, abrasion resistant JFE-EH360LE/EH500LE and high strength JFE-HITEN780LE, all with good weldability and low temperature toughness (down to -40 deg.C), developed for construction and industrial machinery use. Typical chemical compositions, with Nb, V, Ti additions for all the steels, were as follows: 0.15%C, 0.41%Si, 1.20%Mn for JFE-EH360LE; 0.26%C, 0.31%Si, 1.33%Mn for JFE-EH500LE; and 0.15%C, 0.38%Si, 1.18%Mn for JFE-HITEN780LE. Results are presented for y-groove cold cracking as a function of preheating temperature for all steels (MIG/MAG welding), Brinell hardness and Charpy impact for JFE-EH360LE/JFE-EH500LE, and mechanical properties (elongation, tensile and yield strengths) and bending formability for JFE-HITEN780LE.

220928
High performance steel plates for bridge construction - high strength steel plates with excellent weldability realising advanced design for rationalised fabrication of bridges.
NISHIMURA K; MATSUI K; TSUMURA N
JFE Technical Report, no.5. Mar.2005. Special Issue: Steel Plates. pp.30-36. 6 fig., 9 tab., 9 ref.
[in English]
(Originally published in JFE Giho, no.5. Aug.2004. pp.25-30)

Extremely-low carbon bainite-type YP500 MPa grade steel plates (thickness 25 mm, 0.02%C, 0.30%Si, 1.57%Mn; thickness 60 mm, 0.02%C, 0.25%Si, 1.54%Mn; both thicknesses with Cu, Ni, Cr, Nb, Mo, B additions) were developed to meet the requirements of bridge high performance steel (BHS500), and the mechanical properties (yield point, tensile strength, elongation, Charpy impact value and hardness), cold workability, weldability and butt welded joint performance were investigated. Microstructure control by thermo-mechanical controlled rolling and controlled cooling by super-OLAC (on-line accelerated cooling) were applied to produce steels with low weld cracking coefficient. Strain-aged and line-heating tests were performed. Welded joints were prepared by single-layered electrogas welding and multi-layered submerged arc welding. The standards of representative plates for bridge construction, as manufactured by JFE Steel, are summarised.

211734
Leading high performance steel plates [of improved weldability] with advanced manufacturing technologies.
OMATA K; YOSHIMURA H; YAMAMOTO S
NKK Technical Review, no.88. Feb.2003. Special Issue: Compilation of NKK Technology. pp.73-80. 4 fig., 2 tab., 4 ref.
[in English]

A description is presented of an online accelerated cooling process ("Super-OLAC") developed for the manufacture of high performance steel plates resulting in structural steels of higher strength and better weldability; examples of the industrial application of the steels produced using the process are presented. The examples include: high tensile strength steels suitable for use with an ultrahigh heat input welding process and corrosion resistant plates for use in shipbuilding; weldable weathering steels for use in bridge construction; high strength, high weldability steel plates for use in building construction; and steels for use in industrial machines and equipment.

210042
Comparative study on the weldability of different shipbuilding steels.
LAITINEN R; PORTER D; DAHMEN M; KAIERLE S; POPRAWE R
In: Intelligent Technology in Welding and Joining for the 21st Century. Proceedings, International Welding/Joining Conference, Gyeongju, Korea, 28-30 Oct.2002. Publ: [Daejeon, 305-343 Korea]; Korea Welding Society; 2002. Steel (I) Session. Paper ST1-4. pp.222-228. 14 fig., 4 tab., 7 ref.
[in English]
[CD ROM] [Similar paper: Today and Tomorrow in Science and Technology of Welding and Joining. Proceedings, 7th JWS International Symposium (7WS), Kobe, 20-22 Nov.2001. Vol.2. Paper MW1-3. pp.785-790; Weldasearch 206085]

The laser weldability and welding performance of ship hull steel Raex Laser S275 (0.08%C, 0.02%Si, 1.4%Mn, 0.047%Al, 0.16%Pcm, 0.33% Ceq (carbon equivalent), 420MC (0.08%C, 0.02%Si, 1.38%Mn, 0.037%Al, 0.16%Pcm, 0.33%Ceq) were compared with those of conventional structural steel grades D (0.12%C, 0.21%Si, 0.67%Mn, 0.029%Al, 0.17%Pcm, 0.25%Ceq) and EH36 (0.11%C, 0.43%Si, 1.35%Mn, 0.038%Al, 0.20%Pcm, 0.36%Ceq) (thickness up to 12 mm). Ceq (carbon equivalent) and Pcm (a cracking parameter) are calculated from steel composition. Butt joints, skid and stake welded T-joints were examined for tensile strength, hardness, microstructure, bend strength, Charpy V impact toughness, and fatigue strength. Macro-etching and micro-etching were used. Grain boundary ferrite and grain size were also determined.