Impact energy analysis of quenched and tempered fine grain structural steel specimens after weld thermal cycle simulation

The paper presents impact energy results of thermal cycle simulated specimens of quenched and tempered fine grain structural steel S960QL. These results are obtained by examining notched Charpy specimens. Upon performed metallographic analysis and measured hardness, total impact energy is separated into ductile and brittle components

Possibilities of joining techniques application at railway lines joining and maintenance

This paper presents most important techniques which is possible to apply at joining of railway lines as well as maintenance procedure. Beside thermit welding as a older joint process for that job (since 1895.) it is mentioned flash welding as a modern joining technique interesting from the point of cost efficiency. In a case of maintance tasks it is necessary to caunt arc welding processes and thermit welding, too. Authors gave some experimental date collected during investigation on railway lines joining techniques application

Weldability prediction of high strength steel S960QL after weld thermal cycle simulation

This paper presents weld thermal cycle simulation of high strength steel S960QL, and describes influence of cooling time t_8/5 on hardness and impact toughness of weld thermal cycle simulated specimens. Furthermore, it presents analysis of characteristic fractions done by electron scanning microscope which can contribute to determination of welding parameters for S960QL steel

Utjecaj toplinske obradbe na pretvorbu delta-ferita u zavarima austenitnih nerđajućih čelika

Shielded metal arc (SMAW) welded specimens using austenitic consumable materials with different amount of delta-ferrite are annealed in range 650-750 °C through 2-10 hours. Factorial plan 33 with influenced factors regression analyze of measured delta-ferrite values is used. The transformation i.e. decomposition of delta ferrite during annealing was analyzed regarding on weld cracking resistance using metallographic examination and WRC-1992 diagram.Ručno elektrolučno(REL) zavareni uzorci uporabom austenitnog korozijski postojanog dodatnog materijala s različitim udjelima delta ferita, žareni su u području 650-750 °C tijekom 2-10 sati.Korišten je faktorski plan 33 sa regresijskom analizom utjecajnih čimbenika mjerenih vrijednosti delta ferita. Pretvorba odnosno raspad delta ferita za vrijeme žarenja analizirana je s obzirom na otpornost zavara pukotinama metalografski i uporabom WRC-1992 dijagrama

Accelerated weldability investigation of TStE 420 steel by weld thermal cycle simulation

This paper presents accelerated weldability investigation after weld thermal cycle simulation of TStE 420 steel. The method enables single cycle or multiple cycle thermal simulation of base material specimens and obtaining any point in the heat-affected zone (HAZ) of a welded joint. After weld thermal simulation, an investigation of mechanical properties on treated specimens (hardness, toughness…) is foreseen, based on which it is possible to determine weak points in HAZ of a welded joint and inference regarding to base metal weldability

Mechanical clinching process stress and strain in the clinching of EN-AW5754 (AlMg3), and EN AW-5019 (AlMg5) metal plates

This paper presents the results of Finite Element Method numerical simulation performed onEN-AW5754(AlMg3), EN AW-5019 (AlMg5) plates subjected to mechanical clinching. The goal was to observe differences between aluminum plates in the same tool; and to determine the possibility of using the constructed tool for the clinching of Al-Al material combinations. This tool construction is to be produced and tested in laboratory conditions, to elaborate prospective results, and reach additional conclusions

Dependence of hardness and impact energy on cooling time Δt8/5and temperature for S960QL

The paper deals with research into dependence of hardness and impact energy of thermal cycle simulated specimens of fine-grained structural steel S960QL on cooling time from 800 to 500 °C and on tested temperature. Results were obtained by measuring hardness of HV 10 and by experimental testing of Charpy notched tubes on instrumented Charpy hammer. Total impact energy, initiation energy and fracture propagation energy needed for occurrence of fracture is also elaborated. Key words

Učinak postupka platiranja na mehanička svojstva toplinski obrađenog raznovrsnog spoja

The specimens plated by different cladding procedures (hot rolling, submerged arc welding surfacing using strip electrode (SAW) and explosion welding) were heat treated by annealing (650 ºC through 2 hours). Charpy impact energy testing, as well as shear strength testing of clad joints were performed. Testing results indicated significance of cladding procedure and determined heat treatment infl uences on stated mechanical properties.Uzorci platirani različitim postupcima platiranja (toplim valjanjem, elektrolučnim postupkom navarivanja pod prahom elektrodnom trakom (EPP) i eksplozijskim zavarivanjem) toplinski su obrađivani žarenjem (650 ºC tijekom 2 sata). Provedena su ispitivanja Charpy udarne radnje loma kao i smične čvrstoće platiranog spoja. Rezultati ispitivanja utvrđuju značajnost utjecaja postupka platiranja i toplinske obradbe na navedena mehanička svojstva