scholarly journals Determination of Strain and Stress Fields in Welded Joints of S960-QC Steel

2017 ◽  
Vol 62 (4) ◽  
pp. 2081-2087 ◽  
Author(s):  
T. Pała ◽  
I. Dzioba

Abstract The paper presents the results of two butt welded joints by conventional method. The welding process was performed using a variety of linear welding energy. The studies included experimental and computational part. In experimental studies determined the distribution of hardness and mechanical properties of the individual analyzed sections of welded joints. The data obtained were intended to determine the extent of zones in the welded joints that have certain strength characteristics. Also conducted uniaxial tensile tests of welded joints with the registration of displacement fields on the surface of specimens by means of Aramis video-system what the final result are images of strain fields map on the surface of welded joints. The resulting strain values were compared with the results of numerical computations FEM.

Author(s):  
J. Brnic ◽  
M. Canadija ◽  
G. Turkalj ◽  
D. Lanc

In this paper, some interesting, experimentally determined actualities referring to the 50CrMo4 steel are presented. That way, the mechanical properties of the material are derived from uniaxial tensile tests at lowered and elevated temperatures. Engineering stress versus strain diagrams for both mentioned temperatures, curves representing the effect of temperature on specimen elongation, and short-time creep curves are given. Notch impact energy test was also carried out. Taking into consideration the service life of the final product of the mentioned steel widely used in engine and machine technology, all of the mentioned data may be relevant during design and manufacturing procedure.


2013 ◽  
Vol 814 ◽  
pp. 127-134 ◽  
Author(s):  
Liviu Bereteu ◽  
Raul Moisa ◽  
Mihaela Popescu ◽  
Gheorghe Drăgănescu ◽  
Radu Alexandru Rosu ◽  
...  

Applicability of the welded structures in different operating conditions requires experimental research developed in conditions previously imposed for each punctual application. There are analyzed in this case, in terms of vibration testing, some welded joints made with usual tubular steel wire. This is the case of the type carbon steel plates S235 JR according to EN 10025, with a thickness of 3 mm welded with MIG/MAG welding process with R713 tubular wire with a diameter of 1.2 mm, using SelcoNeoMig 3500 equipment. By processing the received signal based on the vibrations response to determine the elastic modulus of the welded structure, which will then be compared both with the modulus value obtained by tensile tests, and with the theoretical value obtained. The results thus obtained will be the basis of design, in optimal conditions of the welded structures regarding the appropriate behavior to the demands imposed.


Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1312 ◽  
Author(s):  
Jacek Górka

The research work and related tests aimed to identify the effect of filler metal-free laser beam welding on the structure and properties of butt joints made of steel 700MC subjected to the TMCP (thermo-mechanically controlled processed) process. The tests involved 10-mm thick welded joints and a welding linear energy of 4 kJ/mm and 5 kJ/mm. The inert gas shielded welding process was performed in the flat position (PA) and horizontal position (PC). Non-destructive testing enabled classification of the tested welded joints as representing the quality level B in accordance with the requirements set out in standard 13919-1. Destructive tests revealed that the tensile strength of the joints was 5% lower than S700MC steel. The results of tensile tests and changes in structure were referred to joints made using the MAG (Metal Active Gas) method. The tests of thin films performed using a high-resolution scanning transmission electron microscope revealed that, during laser beam welding, an increase in dilution was accompanied by an increase in the content of alloying microadditions titanium and niobium, particularly in the fusion area. A significant content of hardening phases in the welded joint during cooling led to significant precipitation hardening by fine-dispersive (Ti,Nb)(C,N) type precipitates being of several nanometres in size, which, in turn, resulted in the reduction of plastic properties. An increase in the concentration of elements responsible for steel hardening, i.e., Ti and Nb, also contributed to reducing the weld toughness below the acceptable value, which amounts to 25 J/cm2. In cases of S700MC, the analysis of the phase transformation of austenite exposed to welding thermal cycles and the value of carbon equivalent cannot be the only factors taken into consideration when assessing weldability.


2020 ◽  
Vol 1012 ◽  
pp. 349-353
Author(s):  
D.B. Colaço ◽  
M.A. Ribeiro ◽  
T.M. Maciel ◽  
R.H.F. de Melo

The demand for lighter materials with suitable mechanical properties and a high resistance to corrosion has been increasing in the industries. Therefore, aluminum appears as an alternative due to its set of properties. The aim of this work was to evaluate residual stress levels and mechanical properties of welded joints of Aluminum-Magnesium alloy AA 5083-O using the Friction Stir Welding process. For mechanical characterization were performed a uniaxial tensile test, Vickers hardness, bending test and, finally, the determination of residual stresses. It was concluded that welding by FSW process with an angle of inclination of the tool at 3o, established better results due to better mixing of materials. The best results of tensile strength and a lower level of residual stresses were obtained using a tool rotation speed of 340 RPM with welding advance speed of 180 mm/min and 70 mm/min.


2015 ◽  
Vol 651-653 ◽  
pp. 950-956 ◽  
Author(s):  
Mohamad Idriss ◽  
Olivier Bartier ◽  
Gérard Mauvoisin ◽  
Charbel Moussa ◽  
Eddie Gazo Hanna ◽  
...  

This work consists of determining the plastic strain value undergone by a material during a forming process using the instrumented indentation technique (IIT). A deep drawing steel DC01 is characterized using tensile, shear and indentation tests. The plastic strain value undergone by this steel during uniaxial tensile tests is determined by indentation. The results show that, the identification from IIT doesn’t lead to an accurate value of the plastic strain if the assumption that the hardening law follows Hollomon law is used. By using a F.E. method, it is shown that using a Voce hardening law improves significantly the identification of the hardening law of a pre-deformed material. Using this type of hardening law coupled to a methodology based on the IIT leads to an accurate determination of the hardening law of a pre-deformed material. Consequently, this will allow determining the plastic strain value and the springback elastic strain value of a material after a mechanical forming operation.


2016 ◽  
Vol 821 ◽  
pp. 435-441 ◽  
Author(s):  
Denisa Bártková ◽  
Jiří Langer ◽  
Petr Dymáček ◽  
Libor Válka

Tests on miniature samples are increasingly used for the determination of mechanical properties of materials available in small volumes (non-destructive or semi-destructive approach). Small punch testing at constant deflection rate (SPT-CDR) of selected magnesium alloys and composites was performed at room temperature. Mechanical properties (yield strength, ultimate strength) were evaluated from SPT and correlated with results of uniaxial tensile tests (UTT). SPT characteristics were converted to uniaxial tensile properties by empirical formulas available in the literature. New formulas more appropriate for magnesium alloys were suggested.


2017 ◽  
Vol 265 ◽  
pp. 755-761 ◽  
Author(s):  
A.K. Tingaev ◽  
M.A. Ivanov ◽  
A.M. Ulanov

We have investigated a possibility of obtaining high-quality welded joints after oxygen and plasma cutting of steel С355 without removing the heat-affected zone (HAZ), in which the changes in chemical, phase and structural compositions are observed. Numerical and experimental studies of the effect of heat input of MAG and Submerged Arc welding on the quality of welded joints are performed. In particular, it was found that when the heat input of welding is at least 6.5 kJ/cm, the metal of HAZ of the edges after cutting is heated during the welding to temperatures above Ас3, which leads to its full recrystallization. When the heat input of welding is at least 10 kJ/cm, the edges after cutting are completely melted and become a part of the welding seam metal. The presence of extensive areas of melting and recrystallization of the edges in the welding process contributes to obtaining high-quality welded joints without removing the HAZ of the edges after cutting. To verify the results of numerical studies, experimental tests of control welded joints were conducted, which showed that the values of bending angle and impact toughness of the welding seam metal and heat affected zone are significantly above the regulatory requirements to quality of welded joints, and not less than the same requirements for steel С355. The obtained results confirm the possibility of revising domestic regulatory requirements for the steel constructions production in terms of the preparation of edges for welding using technologies of thermal cutting without subsequent machining.


2020 ◽  
Vol 184 ◽  
pp. 01028
Author(s):  
Ravindra Kumar Misra ◽  
Rajesh Kumar Porwal

Metal Inert Gas welding is a fast, reliable and cost effective technique for joining of different ferrous materials and steels used in the construction of large structures like Fe410WA, IS2062, SS304, AISI1040 and AISI316 etc. To obtain better quality and performance of the steel welded joints, parameter optimisation of metal inert gas welding procedure and weld heat treatment process is carried out. In optimization work and studies, variables of GMAW process like welding voltage and current, speed of welding, WFR (rate of wire feed), GFR (rate of gas flow), type of gas used and effect of heat treatments are kept changing to get best combinations of input parameters for best quality of welded parts. The quality of welds is evaluated in terms of mechanical properties of welded joints like ultimate tensile and yield strength, elongation, microstructure, heat affected zone and defect free weld joints etc. Model and experimental studies are done in different combinations to get best combination of input parameters for steels. Studies by authors have identified the significance of input parameters in ascending order and some of them also quantified the optimal values of the input parameters. Pre and post weld heat treatment of structures is beneficial in improvement of mechanical and fatigue properties.


The article deals with promising areas of application of pulsed laser welding for products made of silver-based alloys. The results of experimental studies on the choice of modes of pumping, defocusing to improve the quality of the weld and the efficiency of the welding process.


Sign in / Sign up

Export Citation Format

Share Document