The Experts below are selected from a list of 330 Experts worldwide ranked by ideXlab platform
Madhusudhan G Reddy - One of the best experts on this subject based on the ideXlab platform.
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effect of welding processes and consumables on fatigue crack growth behaviour of armour grade quenched and Tempered Steel joints
Defence Technology, 2014Co-Authors: Madhusudhan G ReddyAbstract:Abstract Quenched and Tempered (Q&T) Steels are widely used in the construction of military vehicles due to its high strength to weight ratio and high hardness. These Steels are prone to hydrogen induced cracking (HIC) in the heat affected zone (HAZ) after welding. The use of austenitic stainless Steel (ASS) consumables to weld the above Steel was the only available remedy because of higher solubility for hydrogen in austenitic phase. The use of stainless Steel consumables for a non-stainless Steel base metal is not economical. Hence, alternate consumables for welding Q&T Steels and their vulnerability to HIC need to be explored. Recent studies proved that low hydrogen ferritic Steel (LHF) consumables can be used to weld Q&T Steels, which can give very low hydrogen levels in the weld deposits. The use of ASS and LHF consumables will lead to distinct microstructures in their respective welds. This microstructural heterogeneity will have a drastic influence in the fatigue crack growth resistance of armour grade Q&T Steel welds. Hence, in this investigation an attempt has been made to study the influence of welding consumables and welding processes on fatigue crack growth behaviour of armour grade Q&T Steel joints. Shielded metal arc welding (SMAW) and Flux cored arc welding (FCAW) were used for fabrication of joints using ASS and LHF consumables. The joints fabricated by SMAW process using LHF consumable exhibited superior fatigue crack growth resistance than all other joints.
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dynamic fracture toughness of armour grade quenched and Tempered Steel joints fabricated using low hydrogen ferritic fillers
Journal of Iron and Steel Research International, 2010Co-Authors: Govindaraj Magudeeswaran, Madhusudhan G Reddy, V Balasubramanian, S Sathyanarayanan, A Moitra, S Venugopal, G SasikalaAbstract:The armour grade quenched and Tempered Steel joints fabricated using low hydrogen ferritic Steel (LHF) filler exhibited superior joint efficiency owing to preferential ferrite microstructure in the welds and also they offered required resistance to HIC. However, the combat vehicles used in military operations will be required to operate under a wide range of road conditions ranging from first class to cross country. Structural components in combat vehicles are subjected to dynamic loading with high strain rates during operation. Stress loadings within the vehicle hull of these vehicles are expected to fluctuate considerably and structural cracking especially in welds during the service life of these vehicles can lead to catastrophic failures. Under these conditions, fracture behaviour of high strain rate sensitive structural Steels can be better understood by dynamic fracture toughness (K1d). Hence, an attempt was made to study dynamic fracture toughness of the armour grade quenched and Tempered Steel and their welds fabricated using LHF consumables. The experimental results indicate that the K1d values of the joints fabricated by shielded metal arc welding (SMAW) are higher than those of the joints fabricated using flux cored arc welding (FCAW) process.
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effect of welding processes and consumables on tensile and impact properties of high strength quenched and Tempered Steel joints
Journal of Iron and Steel Research International, 2008Co-Authors: Govindaraj Magudeeswaran, Madhusudhan G Reddy, V Balasubramanian, T S BalasubramanianAbstract:Quenched and Tempered Steels are prone to hydrogen induced cracking in the heat affected zone after welding. The use of austenitic stainless Steel consumables to weld the above Steel was the only available remedy because of higher solubility for hydrogen in austenitic phase. In this investigation, an attempt was made to determine a suitable consumable to replace expensive austenitic consumables. Two different consumables, namely, austenitic stainless Steel and low hydrogen ferritic Steel, were used to fabricate the joints by shielded metal arc welding (SMAW) and flux cored arc welding (FCAW) processes. The joints fabricated by using low hydrogen ferritic Steel consumables showed superior transverse tensile properties, whereas joints fabricated by using austenitic stainless Steel consumables exhibited better impact toughness, irrespective of the welding process used. The SMAW joints exhibited superior mechanical and impact properties, irrespective of the consumables used, than their FCAW counterparts.
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effect of welding processes and consumables on high cycle fatigue life of high strength quenched and Tempered Steel joints
Materials & Design, 2008Co-Authors: Govindaraj Magudeeswaran, Venkatesh Balasubramanian, Madhusudhan G ReddyAbstract:Austenitic stainless Steel (ASS) welding consumables are traditionally used for welding quenched and Tempered Steels as they have higher solubility for hydrogen in austenitic phase. An attempt was made in this investigation to explore an alternate consumable to replace expensive ASS consumables. Austenitic stainless Steel and low hydrogen ferritic Steel were used to fabricate the joints by shielded metal arc welding and flux cored arc welding processes. The joints fabricated using low hydrogen ferritic Steel consumables showed superior fatigue performance than the joints fabricated using ASS consumables.
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hydrogen induced cold cracking studies on armour grade high strength quenched and Tempered Steel weldments
International Journal of Hydrogen Energy, 2008Co-Authors: Govindaraj Magudeeswaran, V Balasubramanian, Madhusudhan G ReddyAbstract:Quenched and Tempered (Q&T) Steels are prone to hydrogen induced cracking (HIC) in the heat affected zone after welding. The use of austenitic stainless Steel (ASS) consumables to weld the above Steel was the only available remedy because of higher solubility for hydrogen in austenitic phase. The use of stainless Steel consumables for a non-stainless Steel base metal is not economical. Hence, alternate consumables for welding Q&T Steels and their vulnerability to HIC need to be explored. Recent studies proved that low hydrogen ferritic (LHF) Steel consumables can be used to weld Q&T Steels, which can give very low hydrogen levels in the weld deposits. In this investigation an attempt has been made to study the influence of welding consumables and welding processes on hydrogen induced cold cracking of armour grade Q&T Steel welds by implant testing. Shielded metal arc welding (SMAW) and flux cored arc welding (FCAW) processes were used for making welds using ASS and LHF welding consumables. ASS welds made using FCAW process offered a higher resistance to HIC than all other welds considered in this investigation.
Govindaraj Magudeeswaran - One of the best experts on this subject based on the ideXlab platform.
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dynamic fracture toughness of armour grade quenched and Tempered Steel joints fabricated using low hydrogen ferritic fillers
Journal of Iron and Steel Research International, 2010Co-Authors: Govindaraj Magudeeswaran, Madhusudhan G Reddy, V Balasubramanian, S Sathyanarayanan, A Moitra, S Venugopal, G SasikalaAbstract:The armour grade quenched and Tempered Steel joints fabricated using low hydrogen ferritic Steel (LHF) filler exhibited superior joint efficiency owing to preferential ferrite microstructure in the welds and also they offered required resistance to HIC. However, the combat vehicles used in military operations will be required to operate under a wide range of road conditions ranging from first class to cross country. Structural components in combat vehicles are subjected to dynamic loading with high strain rates during operation. Stress loadings within the vehicle hull of these vehicles are expected to fluctuate considerably and structural cracking especially in welds during the service life of these vehicles can lead to catastrophic failures. Under these conditions, fracture behaviour of high strain rate sensitive structural Steels can be better understood by dynamic fracture toughness (K1d). Hence, an attempt was made to study dynamic fracture toughness of the armour grade quenched and Tempered Steel and their welds fabricated using LHF consumables. The experimental results indicate that the K1d values of the joints fabricated by shielded metal arc welding (SMAW) are higher than those of the joints fabricated using flux cored arc welding (FCAW) process.
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effect of welding processes and consumables on tensile and impact properties of high strength quenched and Tempered Steel joints
Journal of Iron and Steel Research International, 2008Co-Authors: Govindaraj Magudeeswaran, Madhusudhan G Reddy, V Balasubramanian, T S BalasubramanianAbstract:Quenched and Tempered Steels are prone to hydrogen induced cracking in the heat affected zone after welding. The use of austenitic stainless Steel consumables to weld the above Steel was the only available remedy because of higher solubility for hydrogen in austenitic phase. In this investigation, an attempt was made to determine a suitable consumable to replace expensive austenitic consumables. Two different consumables, namely, austenitic stainless Steel and low hydrogen ferritic Steel, were used to fabricate the joints by shielded metal arc welding (SMAW) and flux cored arc welding (FCAW) processes. The joints fabricated by using low hydrogen ferritic Steel consumables showed superior transverse tensile properties, whereas joints fabricated by using austenitic stainless Steel consumables exhibited better impact toughness, irrespective of the welding process used. The SMAW joints exhibited superior mechanical and impact properties, irrespective of the consumables used, than their FCAW counterparts.
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effect of welding processes and consumables on high cycle fatigue life of high strength quenched and Tempered Steel joints
Materials & Design, 2008Co-Authors: Govindaraj Magudeeswaran, Venkatesh Balasubramanian, Madhusudhan G ReddyAbstract:Austenitic stainless Steel (ASS) welding consumables are traditionally used for welding quenched and Tempered Steels as they have higher solubility for hydrogen in austenitic phase. An attempt was made in this investigation to explore an alternate consumable to replace expensive ASS consumables. Austenitic stainless Steel and low hydrogen ferritic Steel were used to fabricate the joints by shielded metal arc welding and flux cored arc welding processes. The joints fabricated using low hydrogen ferritic Steel consumables showed superior fatigue performance than the joints fabricated using ASS consumables.
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hydrogen induced cold cracking studies on armour grade high strength quenched and Tempered Steel weldments
International Journal of Hydrogen Energy, 2008Co-Authors: Govindaraj Magudeeswaran, V Balasubramanian, Madhusudhan G ReddyAbstract:Quenched and Tempered (Q&T) Steels are prone to hydrogen induced cracking (HIC) in the heat affected zone after welding. The use of austenitic stainless Steel (ASS) consumables to weld the above Steel was the only available remedy because of higher solubility for hydrogen in austenitic phase. The use of stainless Steel consumables for a non-stainless Steel base metal is not economical. Hence, alternate consumables for welding Q&T Steels and their vulnerability to HIC need to be explored. Recent studies proved that low hydrogen ferritic (LHF) Steel consumables can be used to weld Q&T Steels, which can give very low hydrogen levels in the weld deposits. In this investigation an attempt has been made to study the influence of welding consumables and welding processes on hydrogen induced cold cracking of armour grade Q&T Steel welds by implant testing. Shielded metal arc welding (SMAW) and flux cored arc welding (FCAW) processes were used for making welds using ASS and LHF welding consumables. ASS welds made using FCAW process offered a higher resistance to HIC than all other welds considered in this investigation.
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effect of welding consumables on tensile and impact properties of shielded metal arc welded high strength quenched and Tempered Steel joints
Science and Technology of Welding and Joining, 2008Co-Authors: Govindaraj Magudeeswaran, Venkatesh Balasubramanian, T S Balasubramanian, Madhusudhan G ReddyAbstract:AbstractQuenched and Tempered (Q&T) Steels are widely used in the construction of military vehicles due to its high strength to weight ratio and high hardness. These Steels are prone to hydrogen induced cracking in the heat affected zone (HAZ) after welding and HAZ softening. The use of austenitic stainless Steel (ASS) consumables to weld the above Steel was the only remedy because of higher solubility for hydrogen in austenitic phase. Recent studies proved that high nickel Steel (HNS) and low hydrogen ferritic (LHF) Steel consumables can be used to weld Q&T Steels, which can give very low hydrogen levels in the weld deposits. In this investigation an attempt has been made to study the effect of welding consumables on tensile and impact properties of high strength, Q&T Steel joints. Three different consumables, namely ASS, LHF Steel and HNS have been used to fabricate the joints by shielded metal arc welding (SMAW) process. The joints fabricated using LHF Steel electrodes showed superior transverse tensil...
Steven J Thrush - One of the best experts on this subject based on the ideXlab platform.
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wear resistance of medium carbon Steel with different microstructures
Materials, 2021Co-Authors: Xue Han, Zhenpu Zhang, Gary C Barber, Steven J ThrushAbstract:In this research, the tribological properties of different microstructures of medium carbon Steel produced by either an ausTempered process or quenched-Tempered process are investigated. The as-received samples with annealed microstructure (spherodized) are ausTempered to obtain a bainite microstructure or quenched-Tempered to obtain a Tempered martensite microstructure. The tribological performance of these microstructures was studied using a ball-on-disk UMT3 tribometer. The results indicated that both bainite microstructures and Tempered-martensite microstructures produced better wear resistance than pearlite microstructures. At the same hardness level, the ausTempered disk specimens have less cracking due to higher fracture toughness compared to quenched and Tempered Steel. For the disks, Tempered martensite microstructures produced more plastic deformation compared with bainite microstructures. Mild abrasive wear was observed on the harder disks, however, smearing wear was observed on the softer disks. Adhered debris particles were observed on the balls.
Guo Yanchang - One of the best experts on this subject based on the ideXlab platform.
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calculation of the yield and tensile strength in the alloying non quenched Tempered Steel by the electron structure parameters
Progress in Natural Science, 2005Co-Authors: Liu Zhilin, Lin Cheng, Liu Yan, Guo YanchangAbstract:Abstract Based on the phase transformation and strengthening mechanisms during rolling, the strength increments Δσb under different strengthening mechanisms are calculated with the covalent electron number n A of the strongest bond in phase cells of alloys and the interface electron density difference Δρ matching the interface stress in alloys. The calculation method of the finishing rolling yield strength is proposed, and it is integrated with the proposed calculation formulas of strength of non quenched-Tempered Steel. Therefore, the general formulas to simultaneously calculate both the finishing rolling strength and the yield strength of the continuous casting-rolling and non quenched-Tempered Steel are given. Taken the pipeline Steel X70 as an example, the predictions of properties and technological parameters are performed before production or online.
I V Papadopoulos - One of the best experts on this subject based on the ideXlab platform.
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a study on combined torsion and axial load fatigue limit tests with stresses of different frequencies
International Journal of Fatigue, 2008Co-Authors: A Bernasconi, S Foletti, I V PapadopoulosAbstract:The aim of this paper is to investigate the high cycle fatigue behaviour of metals in the case of multiaxial loading where the stresses are of different frequencies. In particular, combined axial load and torsion fatigue tests were performed on specimens made of quenched and Tempered Steel. This material has been chosen because it is commonly employed for the production of mechanical components intensively stressed under lengthy fatigue loads. Two frequency ratios between the shear stress and the normal stress are examined and the resulting fatigue limits from these tests are compared to the results from tests where the shear and normal stress are of the same frequency and in-phase. Moreover, different multiaxial fatigue limit criteria, based on the critical plane concept and on the so-called integral approach, are used to analyse the obtained experimental results. In general, better agreement between predictions and experimental results is achieved by the criteria of the integral approach category.
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independence of the torsional fatigue limit upon a mean shear stress
International Journal of Fatigue, 2003Co-Authors: Paolo Davoli, Mauro Filippini, S Foletti, Alessandro Bernasconi, I V PapadopoulosAbstract:The influence of a superimposed mean shear stress on the high-cycle fatigue endurance limit of metals is a question that has been discussed for a long time but general agreement between among researchers has not yet been reached. Though seemingly a question of minor importance, the hypothesis on such effect is a critical issue in the formulation of high-cycle multiaxial fatigue criteria. The available experimental data referring to fatigue tests on Steels in which a static shear (torsional) stress is superimposed to cyclic torsion have been reviewed, showing that in most cases the effect of static shear stress is negligible as long as the maximum shear stress does not exceed the static shear yield strength. The limited amount of relevant experimental data found in the literature has led the present authors to perform torsion fatigue tests on a quenched and Tempered Steel, commonly employed in highly stressed mechanical components, with different levels of superimposed mean shear stress. The statistical analysis of the test results shows that no significant effect of the superimposed static shear stress may be observed.
