Effect of Ti-Mg Treatment on the Impact Toughness of Heat Affected Zone in 0.15%C-1.31%Mn Steel

2017 ◽  
Vol 89 (3) ◽  
pp. 1700355 ◽  
Author(s):  
Ming-Ming Song ◽  
Chun-Lin Hu ◽  
Bo Song ◽  
Hang-Yu Zhu ◽  
Zheng-Liang Xue ◽  
...  
Keyword(s):  
Impact Toughness ◽  
Heat Affected Zone ◽  
The Impact ◽  
Mn Steel

scholarly journals The Microstructure and Property of the Heat Affected zone in C-Mn Steel Treated by Rare Earth

2019 ◽  
Vol 38 (2019) ◽  
pp. 362-369 ◽  
Author(s):  
Ming-ming Song ◽  
Yu-min Xie ◽  
Bo Song ◽  
Zheng-liang Xue ◽  
Nan Nie ◽  
...  
Keyword(s):  
Rare Earth ◽  
Impact Toughness ◽  
Heat Affected Zone ◽  
Acicular Ferrite ◽  
Steel Matrix ◽  
Impact Properties ◽  
Treated Steel ◽  
The Impact ◽  
Welding Processes ◽  
Mn Steel

AbstractThe microstructures and impact properties of the heat affected zone (HAZ) in steel treated by rare earth (RE) under different welding processes were discussed. The effect of Al on the impact properties of the HAZ in RE treated steel was analyzed. It finds that when the welding t8/5 is smaller than 111 s, the main microstructure in steels is bainite/widmanstatten. The impact toughness of the HAZ is lower than that of the steel matrix. When t8/5 is more than 250 s, the microstructure is mainly acicular ferrite (AF) in the steel treated by RE, and the impact toughness of HAZ is obviously improved. Even under the welding processing with t8/5 about 600 s in RE treated steel can still obtain a lot of AF. While in the steel killed by Al and treated by RE, the main microstructure is parallel cluster of bainite/widmanstatten, and the impact toughness of HAZ is significantly lower than that of low-Al RE treated steel. Al can deteriorate the optimizing of RE treatment on HAZ.

Effect of Welding Processes with High Heat Input on the Microstructure and Toughness of Coarse-Grained Heat-Affected Zone of a High-Strength High-Toughness Steel

2018 ◽  
Vol 937 ◽  
pp. 61-67
Author(s):  
Yu Jie Li ◽  
Jin Wei Lei ◽  
Xuan Wei Lei ◽  
Oleksandr Hress ◽  
Kai Ming Wu
Keyword(s):  
Low Temperature ◽  
Impact Toughness ◽  
Heat Affected Zone ◽  
Heat Input ◽  
High Strength ◽  
High Heat ◽  
Coarse Grained ◽  
Low Temperature Impact Toughness ◽  
The Impact ◽  
Welding Processes

Utilizing submerged arc welding under heat input 50 kJ/cm on 60 mm thick marine engineering structure plate F550, the effect of preheating and post welding heat treatment on the microstructure and impact toughness of coarse-grained heat-affected zone (CGHAZ) has been investigated. The original microstructure of the steel plate is tempered martensite. The yield and tensile strength is 610 and 660 MPa, respectively. The impact absorbed energy at low temperature (-60 °C) at transverse direction reaches about 230~270 J. Welding results show that the preheating at 100 °C did not have obvious influence on the microstructure and toughness; whereas the tempering at 600 °C for 2.5 h after welding could significantly reduce the amount of M-A components in the coarse-grained heat-affected zone and thus improved the low temperature impact toughness.

Effect of Ti, Al and Mg Addition on the Impact Toughness of Heat Affected Zone in Low Carbon Steel

2009 ◽  
Vol 79-82 ◽  
pp. 143-146
Author(s):  
Jiang Hua Ma ◽  
Dong Ping Zhan ◽  
Zhou Hua Jiang ◽  
Ji Cheng He
Keyword(s):  
Carbon Steel ◽  
Impact Toughness ◽  
Heat Affected Zone ◽  
Low Carbon Steel ◽  
Optical Microscope ◽  
Carbon Steels ◽  
Low Carbon ◽  
Welding Simulation ◽  
Mg Addition ◽  
The Impact

In order to understand the effects of deoxidizer such as aluminium, titanium and magnesium on the impact toughness of heat affected zone (HAZ), three low carbon steels deoxidized by Ti-Al, Mg and Ti-Mg were obtained. After smelting, forging, rolling and welding simulation, the effects of Al, Ti and Mg addition on the impact toughness of HAZ in low carbon steel were studied. The inclusion characteristics (size, morphology and chemistry) of samples before welding and the fracture pattern of the specimens after the Charpy-type test were respectively analyzed using optical microscope and scanning electron microscopy (SEM). The following results were found. The density of inclusion in Ti-Mg deoxidized steel is bigger than Ti-Al deoxidized steel. The average diameter is decreased for the former than the latter. The addition of Ti-Mg can enhance the impact toughness of the HAZ after welding simulation. The maximal value of the impact toughness is 66.5J/cm2. The complex particles of MgO-TiOx-SiO2-MnS are most benefit to enhance impact toughness. The improvement of HAZ is attributable to the role of particle pinning and the formation of intergranular ferrite.

Effect of zirconium addition on the impact toughness of the heat affected zone in a high strength low alloy pipeline steel

2008 ◽  
Vol 59 (2) ◽  
pp. 134-139 ◽  
Author(s):  
A.M. Guo ◽  
S.R. Li ◽  
J. Guo ◽  
P.H. Li ◽  
Q.F. Ding ◽  
...  
Keyword(s):  
Impact Toughness ◽  
Heat Affected Zone ◽  
Pipeline Steel ◽  
High Strength ◽  
The Impact ◽  
Zirconium Addition

The effects of prior austenite grain boundaries and microstructural morphology on the impact toughness of intercritically annealed medium Mn steel

2017 ◽  
Vol 122 ◽  
pp. 199-206 ◽  
Author(s):  
Jeongho Han ◽  
Alisson Kwiatkowski da Silva ◽  
Dirk Ponge ◽  
Dierk Raabe ◽  
Sang-Min Lee ◽  
...  
Keyword(s):  
Impact Toughness ◽  
Grain Boundaries ◽  
Prior Austenite ◽  
Austenite Grain ◽  
Medium Mn Steel ◽  
Microstructural Morphology ◽  
The Impact ◽  
Mn Steel ◽  
Prior Austenite Grain

scholarly journals Impact Toughness of Gas Metal Arc Welded HY-80 Steel Plate at Sub-zero Temperatures

2019 ◽  
Vol 269 ◽  
pp. 06003
Author(s):  
Herry Oktadinata ◽  
Winarto Winarto
Keyword(s):  
Impact Toughness ◽  
Weld Joint ◽  
Heat Affected Zone ◽  
High Strength Steel ◽  
Steel Plate ◽  
Gas Metal Arc Welding ◽  
High Strength ◽  
Coarse Grain ◽  
Fracture Appearance ◽  
The Impact

Various welding methods are widely applied in large fabrication of high strength steel. However, commonly the problem occurs where a coarse grain is formed near fusion zone causing reduce the impact toughness due to the weld joint become brittle. Ductility and toughness in a coarse grain heat affected zone (CGHAZ) is low due to the formation of coarsening grain size. The objective of this research is to investigate the microstructure evolution, impact toughness and fracture appearance at sub-zero temperatures of the high strength steel arc welded. The steel that used in this experiment is a HY-80 steel welded by gas metal arc welding (GMAW) with a mixture of argon and carbon dioxide (90%Ar and 10%CO2) and ER100S solid wire. Microstructure observation and Charpy V-notch (CVN) tests were performed on the weld joint which consist of base metal (BM), heat affected zone (HAZ), and weld metal (WM). The CVN tests on the HY-80 steel plate at various temperatures (20, -20, -60 and -80 °C) show impact toughness decrease when the test temperature decrease. The CVN tests on the HY-80 weld joint at a temperature of 80 °C show the lowest impact toughness was measured at WM (61 J) and followed fusion line-FL (101 J) with brittle fracture appearance.

Mechanical Behaviour of Intercritically Reheated Coarse-Grained Heat Affected Zone in High Strength Line Pipe Steels

2018 ◽  
Author(s):  
Madhumanti Mandal ◽  
Warren J. Poole ◽  
Thomas Garcin ◽  
Matthias Militzer ◽  
Laurie Collins
Keyword(s):  
Impact Toughness ◽  
Heat Affected Zone ◽  
Welding Process ◽  
Charpy Impact ◽  
High Strength ◽  
Coarse Grained ◽  
Fracture Mechanisms ◽  
Line Pipe ◽  
Secondary Cracks ◽  
The Impact

Multipass welding of high strength steels used for fabrication and joining of transmission pipelines presents a number of metallurgical challenges. A key concern is both the strength and toughness of the heat affected zone (HAZ) adjacent to both seam and girth welds. In this work, a systematic study has been conducted on regions of the heat affected zone in the base metal where the first welding pass produces a thermal excursion which results in a coarse-grained heat affected zone (CGHAZ). The subsequent weld pass involves intercritical annealing of this region, i.e. a microstructure associated with intercritically reheated coarse grain heat affected zone (ICCGHAZ). The small ICCGHAZ region is often identified as being particularly susceptible to crack initiation. This work was undertaken to understand microstructure development in this zone and how the ICCGHAZ may affect the overall performance of the HAZ. Gleeble thermomechanical simulations have been conducted to produce bulk samples representative of different welding scenarios. Charpy impact tests and tensile tests have been performed over a range of temperatures. It was found that when a continuous necklace of martensite-austenite islands form on the prior austenite grain boundaries (i.e. for a M/A fraction of ≈10%), the Charpy impact toughness energy is dramatically decreased and the ductile brittle transition temperature is significantly raised. Detailed studies on the secondary cracks have been conducted to examine the fracture mechanisms in the different microstructures. The results show that the lower bainite microstructures obtained after the 1st thermal treatment, representative of CGHAZ have excellent impact properties. The impact toughness of the microstructures typical of ICCGHAZ is strongly dependent on the composition as well as morphology and spatial distribution of the resulting martensite-austenite (M/A) islands transformed from inter-critically formed austenite. This zone can play a significant role in fracture initiation and thus needs to be considered in alloy and welding process designs.

scholarly journals A Fractographical Study on Dissimilar Weld Joints of SAF 2205 and Hastelloy C-276

2018 ◽  
Vol 188 ◽  
pp. 02018
Author(s):  
Emrullah Çelikkol ◽  
Mustafa Tümer ◽  
Ş. Hakan Atapek ◽  
M. Zaim Kerimak
Keyword(s):  
Impact Toughness ◽  
Fracture Surface ◽  
Heat Affected Zone ◽  
Root Zone ◽  
Welding Parameters ◽  
Face Centered Cubic ◽  
Dissimilar Weld ◽  
Gas Tungsten Arc ◽  
Saf 2205 ◽  
The Impact

In this study, a dissimilar weld joint between SAF 2205 and Hastelloy C-276 was manufactured by using gas tungsten arc welding and its notched impact fracture behaviour was investigated. Initially, V-type welding mouth was opened and the welding was performed by multi-pass. In welding procedure, ERNiCrMo-3 material used as a filler metal and the heat input was varied between 0.48-1.10 kJ/mm depending on welding parameters. Both welding pool and root zone were protected by an argon atmosphere. Multi notched impact tests were performed at room temperature. Weld metal had an impact toughness value as 92 J and its fracture surface exhibited several oriented cracking paths due to its solidified structure. The impact toughness value was measured as 82 J for heat affected zone of SAF 2205 and its fractograph reflected the coarser and deeper dimples. Heat affected zone of nickel based alloy had the highest impact toughness value as 116 J among the studied joints due to the more plastic deformation capability of nickel having face centered cubic structure, however, its fracture surface under impact loading exhibited several cracks propagating throughout the fusion line having equiaxed dendrites.

Study in Simulated Heat-Affected Zone of Ship Steel

2011 ◽  
Vol 228-229 ◽  
pp. 1196-1200
Author(s):  
Wen Yan Liu ◽  
Ji Bin Liu ◽  
Cong Mao Zhu ◽  
Hui Wang
Keyword(s):  
Impact Toughness ◽  
Heat Affected Zone ◽  
Heat Input ◽  
Physical Simulation ◽  
Wide Range ◽  
Lath Bainite ◽  
Quench Hardening ◽  
Impact Energies ◽  
The Impact ◽  
Cct Diagrams

The experiments were carried out upon the determination of simulated heat-affected zone continuous cooling transformation (SH-CCT) diagrams, the characteristics of microstructure and Vickers hardness of SH-CCT specimens, and impact toughness in simulated coarse grain heat-affected zone (CGHAZ) of ship steels under different heat input based on physical simulation. The SH-CCT diagram reveals that bainite is always obtained in a wide range of cooling rates. When the maximum cooling rate reaches 100 °C/s (t8/5=3 seconds), the maximum fraction of martensite (8%) is obtained and the microstructures mainly consist of lath bainite and the hardness is only 255 HV. This demonstrates that the steel has a low quench-hardening tendency and excellent resistance to cold cracking. There are no obvious hardening and softening phenomena in simulated CGHAZ. Test results of impact toughness under different heat input in simulated CGHAZ show that the impact energies reach over 30 J at -40 °C when t8/5 is less than 20 s, meeting the stipulated requirements of ship steel (≥22 J at -40 °C) but no great allowance. Thus, to meet the requirement of properties during welding, it is proposed to choose t8/5 ranging from 5 to 20 s, correspondently the line energies ranging from 14 to 37 KJ/cm for 30 mm thick plate.

scholarly journals Comparison of Impact Toughness in Simulated Coarse-Grained Heat-Affected Zone of Al-Deoxidized and Ti-Deoxidized Offshore Steels

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1783
Author(s):  
Henri Tervo ◽  
Antti Kaijalainen ◽  
Vahid Javaheri ◽  
Mohammed Ali ◽  
Tuomas Alatarvas ◽  
...  
Keyword(s):  
Impact Toughness ◽  
Heat Affected Zone ◽  
Electron Backscatter Diffraction ◽  
Cooling Time ◽  
Coarse Grained ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electron Backscatter ◽  
Backscatter Diffraction ◽  
The Impact

The presence of acicular ferrite (AF) in the heat-affected zone (HAZ) of steels used offshore is generally seen as beneficial for toughness. In this study, the effects of varying fractions of AF (0–49 vol.%) were assessed in the simulated, unaltered and coarse-grained heat-affected zones (CGHAZ) of three experimental steels. Two steels were deoxidized, with one using Ti and the other using Al. The characterization was carried out by using electron microscopy, energy-dispersive X-ray spectrometry, electron backscatter diffraction and X-ray diffraction. The fraction of AF varied with the heat input and cooling time applied in the Gleeble thermomechanical simulator. AF was present in one of the Ti-deoxidized steels with all the applied cooling times, and its fraction increased with increasing cooling time. However, in other materials, only a small fraction (13–22%) of AF was present and only when the longest cooling time was applied. The impact toughness of the simulated specimens was evaluated using instrumented Charpy V-notch testing. Contrary to the assumption, the highest impact toughness was obtained in the conventional Al-deoxidized steel with little or no AF in the microstructure, while the variants with the highest fraction of AF had the lowest impact toughness. It was concluded that the coarser microstructural and inclusion features of the steels with AF and also the fraction of AF may not have been great enough to improve the CGHAZ toughness of the steels investigated.

Sign in / Sign up

Export Citation Format

Share Document