Effect of Process Parameters on Seam Weld Quality of ZM21 Tubes

2012 ◽  
Vol 504-506 ◽  
pp. 487-492 ◽  
Author(s):  
Antonio Segatori ◽  
Barbara Reggiani ◽  
Lorenzo Donati ◽  
Tommaso Pinter ◽  
Y. Rami ◽  
...  

The increasing attention to magnesium alloys in extruded profiles, especially in the transportation industry, is related to their low density associated with good mechanical properties and complete recyclability. This allows to push towards both increasing efficiency and pollution restrictions. However, these advantages are negatively balanced by the production rates drop in relation to dangerous profile temperatures increasing that force to keep low velocities. In this context, a novel porthole die has been purposely designed for magnesium alloys allowing an increasing of the process velocity up to four times with respect to past solutions. The mandrel consisted of three ports made by 120° bridges that created an equal number of seam welds. The extruded tubes, made in ZM21, were 50 mm in diameter and 2 mm in thickness and were tested under different process conditions. In the present work, the quality of the seam welds has been investigated in relation to each process condition by means of the rubber plug testing method that allowed to applied an hydrostatic tensile state.

2020 ◽  
Vol 8 (5) ◽  
pp. 3662-3668

In conventional manufacturing procedures liable upon the forces acting on the materials may lead to breakage during motion of the part undergoing construct which is inevitable to no change its shape and position. In pretty much every case, materials have anisotropic by its nature and virtue. As additive manufacturing (AM) techniques embedded undergoing processes with improved accuracy of the parts being developed. Since there is far disadvantage of the quality of the AM product, constantly improvements made the process of AM is being escalating than conventional process. The assessment of the product and the complexity of the parts can’t be resolved or found before it developing a methodology which impact mechanical properties of the printed parts. An effort has been made in the present work to improve the products mechanical properties by increasing the infill percentage. Study has been carried out as in view of increased infill with elaborated percentages of 15%, 30%, 40% and 50% to enhance the mechanical properties of the parts.


2014 ◽  
Vol 1000 ◽  
pp. 59-62
Author(s):  
Hana Kalousová ◽  
Eva Bartoníčková ◽  
Tomáš Opravil

The presented paper deals with the issue of influence of storage conditions on the quality of conventional fly ashes which are produced by combustion of lignite. These ashes were stockpiled for long time. A borehole for sampling was made in the fly ash stock-pile. Total depth of the borehole was 20 m. Samples of fly ashes taken from every single meter were analyzed and next mechanical properties and the volume stability of materials containing these fly ashes were tested. The quality of fly ashes especially with respect to the possibility to use them as components of pastes, mortars and concretes as pozzolanic admixture or fine filler was evaluated.


2015 ◽  
Vol 651-653 ◽  
pp. 713-718 ◽  
Author(s):  
Marion Merklein ◽  
Raoul Plettke ◽  
Daniel Junker ◽  
Adam Schaub ◽  
Bhrigu Ahuja

The quality of additive manufactured parts however depends pretty much on the workers experience to control porosity, layer linkage and surface roughness. To analyze the robustness of the Laser Beam Melting (LBM) process a Round Robin test was made in which specimens from four institutes from different countries were tested and compared. For the tests each institute built a set of specimens out of stainless steel 1.4540. The aim of this work is to analyze the influence of the process parameters on the mechanical properties. The results show that there is a high potential for additive manufacturing but also a lot of further research is necessary to optimize this technology.


1998 ◽  
Vol 521 ◽  
Author(s):  
J. Burzer ◽  
T. Bernard ◽  
H. W. Bergmann

ABSTRACTThe aim of this work is the evaluation of new construction elements for applications in transportation industry which are based on new designs incorporating commonly applied aluminium structures and aluminium foams. The work includes the characterisation of the joining process, the joining mechanism and the mechanical properties of the joining zone. A testing method for the joints is developed which is based on a common tensile test in order to evaluate the influence of the main laser welding parameters on the toughness of the joints and to afford a comparison between laser beam welding and gluing process. The analysis of the joining mechanism is investigated with the help of metallographic studies. In addition, the energy absorption properties of aluminium hollows filled and joined with foam structures are characterised.


2016 ◽  
Vol 866 ◽  
pp. 196-200
Author(s):  
Sun Ho Jung ◽  
S. Lee ◽  
J. Lee

Band structures with pearlite and ferrite aligned as stripes can be created during the heat treatment of carbon steel. Since band structures undermine the mechanical quality of end products, it is highly important to select a process condition that will not create band structures as a result of heat treatment. This study verified the effect of temperature and cooling rate on the creation of band structures during heat treatment of 35MnB and 25Mn steel tubes for drive shafts and also considered the optimal process conditions to remove band structures or prevent their creation. The experimental results suggest that, during heat treatment of 35MnB and 25Mn steel tubes, it is most effective to ensure a cooling rate faster than furnace cooling in order to prevent band structures.


Author(s):  
C. Senfuka ◽  
J. B. Kirabira ◽  
J. K. Byaruhanga

All steel made in Uganda is currently manufactured from scrap. Such steel has often been characterized by unpredictable performance in consonance with its inconsistent raw material inputs. This study evaluates and relates the mechanical, metallurgical and geometrical properties of these bars in order to identify the factors underlying the performance of the products from this steel and examine the relationship with their scrap content. In order to study the steels, tensile, torsion and micrographic tests have been carried out together with spark emission spectrometry on samples collected from different plants. The test results generally indicate impressive steel resilience, strength and metallographic properties in spite of relatively high and irregular carbon content. Limited weldability, uniaxiality of properties, uneven scatter of microelements and substantial non-uniformity of longitudinal mechanical properties have been observed. Rolling and post rolling defects have been noted. The geometric reliability of the bars has also been found generally low. Improvement of secondary refinement, use of direct reduced iron (DRI) diluent and more diligent sorting have suggested as solutions.


2019 ◽  
Vol 17 (1) ◽  
pp. 37
Author(s):  
Muas M ◽  
Muhammad Arsyad Suyuti ◽  
Rasul Rasul ◽  
Patta Hajji

The purpose of this research is to know the mechanical properties of the welds due to the current variation of welding joint API 5L using TIG and SMAW welding root methods. Preparation of specimens of pipe API 5L PSL1 grade X56 (Ø 177.8 mm, length 200 mm, width 7 mm), then specimens preparation were made in a single V 600, root gap 2mm, root face 2mm. Filling the welding roots with TIG welding and SMAW using electrodes E7018 with a current variation 70A, 80A, 90A. Mechanical tests consist of tensile, bending and hard test. The results showed that the quality of a good TIG root weld at 70A, the highest tensile strength of the weld joint 52.27 kgf/mm2 (70A), the highest hardnest 164,217 HRB (90A), the bending strength 1.123,061 N/mm2 (70A) using face bend method and 1,172,959 N/mm2 with root bend. In SMAW root welding, the highest tensile strength 54.27 kgf/mm2 (70 A) , the highest hardnest  158.717 HRB (70 A), the highest bending strength 1.115,611 N/mm2 (70 A) using face bend method, and 1.161,748 N/ mm2 with root bend. 


2013 ◽  
Vol 197 ◽  
pp. 125-130
Author(s):  
Bartłomiej Dybowski ◽  
Robert Jarosz ◽  
Andrzej Kiełbus

Magnesium alloys are widely used in aerospace and automotive industry due to their low density, good mechanical properties and good castability. The paper presents results of the castability tests and microstructural investigations on two unmodified magnesium casting alloys, Elektron 21 and QE22. Spirals for the castability test were poured from three temperatures: 755°C, 800°C and 835°C. Volume fraction of eutectic regions and grain size in both alloys were quantitatively evaluated. Castability increased with increasing pouring temperature. Quantity of eutectics and grain size did not show straight correlation with pouring temperature.


2009 ◽  
Vol 28 (4) ◽  
pp. 289-302 ◽  
Author(s):  
J. Escudero ◽  
E. Solórzano ◽  
M.A. Rodriguez-Perez ◽  
F. Garcia-Moreno ◽  
J.A. De Saja

Structural foams are composed of two solid layers enclosing a foamed core. The application of sandwich structural foams has rapidly increased in the last decade. Injection moulding is currently used to produce these foams, being not common to produce conventional foams of similar densities and chemical compositions in a similar process. In this paper an alternative route to produce structural foams has been used. This method allows fabricating conventional foams with the same chemical composition and density than the structural foams, so comparisons between properties of both kinds of materials can be made in a proper way, i.e. avoiding effects of different chemical compositions and/or different densities. The structural and mechanical properties in tension, compression and bending have been characterized both for structural and conventional foams based on a low density polyethylene. The results have showed that the sandwich structure of structural foams improves a 50% the mechanical behaviour in bending, however no improvements in compression or tension have been found.


1988 ◽  
Vol 142 ◽  
Author(s):  
Humphrey J. Maris ◽  
Holger T. Grahn ◽  
Jan Tauc

AbstractWe describe a technique by which ultrasonic measurements can be made in the picosecond time domain. A light pulse (duration of the order of 0.1 psec) is absorbed at a surface, thereby setting up an elastic stress. This stress launches an elastic pulse into the interior. The propagation of this strain, including its reflection at interfaces within a microstructure, is monitored through measurements of the time-dependent changes of the optical reflectivity. These measurements are made using a time-delayed probe pulse. In these experiments the spatial length of the elastic pulses can be as short as 50 Å. We can therefore use this technique to perform a nondestructive ultrasonic evaluation of thin-film microstructures. We describe here results we have obtained which demonstrate the application of the method to the study of the mechanical properties of thin films, the geometry of microstructures, and the quality of bonding at interfaces.


Sign in / Sign up

Export Citation Format

Share Document