检索结果-南通市图书馆

Metallurgical characteristics of armour steel welded joints used for combat vehicle construction

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2018年第5期14卷 590-606页

作者： g.magudeeswaran V.Balasubramanian g.Madhusudan Reddy Department of Mechanical Engineering PSNA College of Engineering and TechnologyKothandaraman NagarMuthanampatti624 622DindigulTamilnaduIndia Centre for Materials Joining&Research Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar608002Tamil NaduIndia Outstanding Scientist & Associate Director Defence Metallurgical Research LaboratoryKanchanbaghHyderabad500058TelanganaIndia

Austenitic stainless steel(ASS) and High nickel steel(HNS) welding consumables are being used for welding Q&T steels, as they have higher solubility for hydrogen in austenitic phase, to avoid hydrogen induced cracking(HIC) but they are very expensive. In recent years, the developments of low hydrogen ferritic steel(LHF) consumables that contain no hygroscopic compounds are utilized for welding Q&T steels. Heat affected zone(HAZ) softening is another critical issue during welding of armour grade Q&T steels and it depends on the welding process employed and the weld thermal cycle. In this investigation an attempt has been made to study the influence of welding consumables and welding processes on metallurgical characteristics of armour grade Q&T steel joints by various metallurgical characterization procedures. Shielded metal arc welding(SMAW) and flux cored arc welding(FCAW) processes were used for making welds using ASS, LHF and HNS welding consumables. The joints fabricated by using LHF consumables offered lower degree of HAZ softening and there is no evidence of HIC in the joints fabricated using LHF consumables.

关键词： Armour grade Q&T steel Heat affected zone softening Shielded metal arc welding process Flux cored arc welding process Austenitic stainless steel Low hydrogen ferritic steel High nickel steel

Experimental Investigation on the Performance of Armour grade Q&T Steel Joints Fabricated by Flux Cored Arc Welding with Low Hydrogen Ferritic Consumables

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2009年第5期25卷 583-591页

作者： g.magudeeswaran V.Balasubramanian g.Madhusudhan Reddy g.gopalakrishnan Metal Joining Research Center(MJRC) Sri Ramakrishna Engineering CollegeN.G.G.O Colony-Post Centre for Materials Joining&Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Scientist-F Metal Joining SectionDefence Metallurgical Research Laboratory(DMRL)Kanchanbagh(P.O)

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） and softening 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 to avoid HIC because of higher solubility for hydrogen in austenitic phase. Recent studies revealed that low hydrogen ferritic （LHF） steel consumables can also be used to weld Q＆T steels, which can give very low hydrogen levels in the weld deposits and required resistance against cold cracking. Hence, in this investigation an attempt has been made to study the performance of armour grade Q＆T steel joints fabricated by flux cored arc welding with LHF steel consumables. Two different consumables namely （i） austenitic stainless steel and （ii） low hydrogen ferritic steel have been used to fabricate the joints by flux cored arc welding （FCAW） process. The joints fabricated by LHF consumable exhibited superior transverse tensile properties due to the presence of ferrite microstructure in weld metal. The joints fabricated by ASS consumable showed higher impact toughness due to the presence of austenitic phase in weld metal microstructure. The HAZ softening in coarse grain heat affected zone （CgHAZ） is less in the joints fabricated using LHF consumable due to the lower heat input involved during fabrication compared to the joints fabricated using ASS consumables.

关键词： Quenched and tempered steel Flux cored arc welding process Low hydrogen ferritic steel Tensile properties

Effect of welding processes and consumables on fatigue crack growth behaviour of armour grade quenched and tempered steel joints

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2014年第1期10卷 47-59页

作者： g.magudeeswaran V.BALASUBRAMANIAN g.MADHUSUDHAN REDDY Department of Mechanical Engineering PSNA College of Engineering & Technology Kothandaraman Nagar Muthanampatti Centre for Materials Joining & Research Department of Manufacturing Engineering Annamalai University Metal Joining group Solidification Technology Division Defence Metallurgical Research LaboratoryKanchanbagh

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.

关键词：焊接工艺疲劳裂纹扩展行为消耗品钢接头装甲回火淬火

Optimization of process parameters of the activated tungsten inert gas welding for aspect ratio of UNS S32205 duplex stainless steel welds

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2014年第3期10卷 251-260页

作者： g.magudeeswaran Sreehari R.NAIR L.SUNDAR N.HARIKANNAN Department of Mechanical Engineering PSNA College of Engineering and Technology Ador Welding Limited Melakottaiyur

The activated TIg(ATIg) welding process mainly focuses on increasing the depth of penetration and the reduction in the width of weld bead has not been paid much *** shape of a weld in terms of its width-to-depth ratio known as aspect ratio has a marked influence on its solidification cracking *** major influencing ATIg welding parameters,such as electrode gap,travel speed,current and voltage,that aid in controlling the aspect ratio of DSS joints,must be optimized to obtain desirable aspect ratio for DSS *** in this study,the above parameters of ATIg welding for aspect ratio of ASTM/UNS S32205 DSS welds are optimized by using Taguchi orthogonal array(OA)experimental design and other statistical tools such as Analysis of Variance(ANOVA) and Pooled ANOVA *** optimum process parameters are found to be 1 mm electrode gap,130 mm/min travel speed,140 A current and 12 V *** aspect ratio and the ferrite content for the DSS joints fabricated using the optimized ATIg parameters are found to be well within the acceptable range and there is no macroscopically evident solidification cracking.

关键词： Duplex stainless steel ATIg welding Aspect ratio Taguchi design Ferrite number Solidification cracking

在线全文

学校读者我要写书评

暂无评论

Preface

Defence Technology（防务技术） 2015年第3期11卷 187-187页

作者： K.Prasad Rao g.Madhusudhan Reddy Huijie Liu V.Balasubramanian g.magudeeswaran University of UTAH Defence Metallurgical Research Laboratory Harbin Institute of Technology Annamalai University PSNA College of Engineering & Technology

The increased use of newer materials adds to challenge of joining and fabrication in sectors that manufacture defence ***,Materials Joining is a state of art in today's industrial scenario that integrates structures f... 详细信息

关键词：知识更新新材料军事应用集成结构技术人员研究人员工程师制造

Effect of Welding Processes and Consumables on Tensile and Impact Properties of High Strength Quenched and Tempered Steel Joints

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2008年第6期15卷 87-94页

作者： g.magudeeswaran V Balasubramanian g Madhusudhan Reddy T S Balasubramanian Center for Advanced Materials Joining and Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Metal Joining Section Defence MetallurgicalResearch Laboratory Special Vehicles Division Combat Vehicles Research and Development Establishment

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, austenitie stain less steel and low hydrogen ferritic steel, were used to fabricate the joints by shielded metal are 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.

关键词： shielded metal arc welding process flux cored arc welding process austenitie stainless steel low hydro gen ferritic steel transverse tensile property impact toughness

Dynamic Fracture Toughness of Armour grade Quenched and Tempered Steel Joints Fabricated Using Low Hydrogen Ferritic Fillers

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2010年第5期17卷 51-56页

作者： g.magudeeswaran V Balasubramanian S Sathyanarayanan g Madhusudhan Reddy A Moitra S Venugopal g Sasikala Department of Mechanical Engineering Pannaikkadu Veerammal Paramasivam College of Engineering andTechnology for Women Department of Manufacturing Engineering Annamalai University Materials Mechanics Section Indira Gandhi Center for Atomic Research Metal JoiningSection Defence Metallurgical Research Laboratory

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.

关键词： quenched steel tempered steel low hydrogen ferritic steel dynamic fracture toughness