Hydroformability of Bulge Forming Light-Weight Tubes via Micro-Hardness Dependence

2011 ◽  
Vol 465 ◽  
pp. 149-152
Author(s):  
G.D. Wang ◽  
Luen Chow Chan
Keyword(s):  
Vickers Hardness ◽  
Tube Hydroforming ◽  
Hardness Measurement ◽  
Light Weight ◽  
Micro Hardness ◽  
Forming Process ◽  
Material Hardness ◽  
Before And After ◽  
Hardness Values ◽  
Tubular Components

To evaluate the hydroformablility of tubular components in the tube hydroforming (THF) process, the conventional method is to measure the deformed square or circle grids printed on the surface of the tubular parts. However, the reliability of those measured data is affected greatly by the grid size and its measurement method on the curved surface. It is well-known that material hardness varies under different plastic deformation conditions, especially before and after the forming process. And it is more convenient to obtain the Vickers’ hardness values and distribution around the burst area of deformed components. This paper mainly presents an effective and reliable approach to evaluate the hydroformability of tubular components using micro-hardness measurement. At first, the Vickers’ hardness values and distribution around the burst area of the deformed components were obtained. The plastic strain, together with its distribution in such an area could then be derived by the measured micro-hardness through the developed equations. As a result, it was found to be more suitable to evaluate the hydroformability of tubes using this approach instead of the traditional grids measurement.

Positron Annihilation & Micro-Hardness Measurement of 6063 and 6066 with Compromise with Ingot Al

2010 ◽  
Vol 295-296 ◽  
pp. 39-47 ◽  
Author(s):  
M.A. Abdel-Rahman ◽  
Alaa Aldeen Ahmed ◽  
Emad A. Badawi
Keyword(s):  
Positron Annihilation ◽  
Vickers Hardness ◽  
Hardness Measurement ◽  
Micro Hardness ◽  
Quenching Temperature ◽  
Lifetime Measurements ◽  
Positron Annihilation Lifetime ◽  
Different Temperatures ◽  
Hardness Values ◽  
Knoop Indenter

The aim of this work was to study the resistance of this type of alloy to quenching. Hardness measurements can be defined as macro-, micro- or nano- scale, according to the forces applied and the displacements obtained. This effect can also be studied using a nuclear, (PALT): positron annihilation lifetime, technique [1]. Microhardness is the hardness of a material, as determined by forcing an indenter such as a Vickers or Knoop indenter into the surface of the material under a 15 to 1000gf load; the indentations are usually so small that they must be measured using a microscope. These samples were quenched at different temperatures ranging from 50 to 500oC. We studied the effect of the quenching temperature upon the hardness measurements. We also studied this variation via the positron annihilation (lifetime) parameter. It is clear from the Vickers hardness that 1050 has the lowest value of Hv, while 6063 is higher and 6066 has the highest values of Hv. Also we could observe ( recognize) that the Hv (number) is reduce as a function of temperature (6066) but for (1050) and (6063) there is no observation of a variation in Hv (number) as a function of quenching temperature. The same observation was also made for 1050, 6063 and 6066 via the lifetime measurements. Here, 6063, 6066 give higher values than 1050. It is clear that the data from both techniques (positron annihilation lifetime and Vickers hardness) for 1050 ingot Al gives lower values of both parameters for Hv and lifetime technique. While Hv for 6066 is higher than the values of 6063 alloy at the same quenching temperature. Using the lifetime technique, one cannot distinguish between the 6063 and 6066 alloys. The applied force has no real effect upon the levels of the hardness values. Also, alloys 6066 and 6063 were defined as heat-treatable alloys but 1050 is not a heat-treatable alloy. The Hv of the 1050 is not affected by the changes in quenching temperature. Alloy 6066 heat-treatable alloy is more affected by the heat treatment than is 6063 alloy, and this is related to the structure of the precipitates in these alloys since 6066 alloy has much more Si and Mg than does the 6063 alloy. The Hv values vary from 14 to 23.9 for 6063 alloy and from 15.7 to 69.8 for 6066 alloy; in comparison with ingot alloy (1050) where it varies from 10.4 to 18.6.

scholarly journals Enhancement of the Wear Resistance and Microhardness of Aluminum Alloy by Nd:YaG Laser Treatment

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Haitham T. Hussein ◽  
Abdulhadi Kadhim ◽  
Ahmed A. Al-Amiery ◽  
Abdul Amir H. Kadhum ◽  
Abu Bakar Mohamad
Keyword(s):  
Wear Resistance ◽  
Aluminum Alloy ◽  
Wear Rate ◽  
Laser Treatment ◽  
Vickers Hardness ◽  
Nd:Yag Laser ◽  
Wear Behavior ◽  
X Ray ◽  
Before And After ◽  
Hardness Values

Influence of laser treatment on mechanical properties, wear resistance, and Vickers hardness of aluminum alloy was studied. The specimens were treated by using Nd:YaG laser of energy 780 mj, wavelength 512 nm, and duration time 8 ns. The wear behavior of the specimens was studied for all specimens before and after treatment by Nd:YaG laser and the dry wear experiments were carried out by sing pinon-disc technique. The specimens were machined as a disk with diameter of 25 mm and circular groove in depth of 3 mm. All specimens were conducted by scanning electron microscopy (SEM), energy-dispersive X-ray florescence analysis (EDS), optical microscopy, and Vickers hardness. The results showed that the dry wear rate was decreased after laser hardening and increased Vickers hardness values by ratio of 2.4 : 1. The results showed that the values of wear rate for samples having circular grooves are less than samples without grooves after laser treatment.

scholarly journals Mg65Ni20Y15–XAgX (X = 1, 2, 3, 5) alloys prepared via atmosphere controlled induction system

2018 ◽  
Vol 96 (7) ◽  
pp. 810-815 ◽  
Author(s):  
Celal Kursun ◽  
Musa Gogebakan ◽  
Yunus Azakli ◽  
Sezgin Cengiz ◽  
Hasan Eskalen ◽  
...  
Keyword(s):  
Hardness Measurement ◽  
Microstructural Properties ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Induction System ◽  
Quantitative Results ◽  
Hardness Values ◽  
Vickers Micro Hardness ◽  
Scanning Electron

In this work, Mg65Ni20Y15–XAgX (X = 1, 2, 3, 5) alloys were manufactured by atmosphere controlled induction system. The effect of Ag ratio on the microstructural properties, micro-hardness, density, and homogeneity of the Mg–Ni–Y alloys were investigated. These alloys were characterized by X-ray diffraction (XRD), optical microscopy, scanning electron microscopy with energy dispersive X-ray (SEM-EDX) and Vickers micro-hardness measurement. According to XRD results, Ni3Y and Mg6Ni phases were observed as well as AgY and Ag17Mg54 phases, which were obtained in alloys. The quantitative results of EDX analysis confirm that the chemical composition of the obtained phases is very close and their homogeneities are so high. The average micro-hardness values of the ingot alloys were measured between 208 and 266 HV for matrix. The elastic modulus and densities of the Mg65Ni20Y15–XAgX (X = 1, 2, 3, 5) alloys increased by increasing Ag in the alloys and they were determined in the range of 58.18–68.12 GPa and 3.14–3.53 g/cm3, respectively.

Effect of Natural and Artificial Aging on the Mechanical Properties of Two Al-Mg-Si Alloys

2017 ◽  
Vol 28 ◽  
pp. 1-7 ◽  
Author(s):  
Karim Djemmal ◽  
Hichem Farh ◽  
Rebai Guemini ◽  
Mosbah Zidani ◽  
Fares Serradj
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Vickers Hardness ◽  
Artificial Aging ◽  
Hardness Measurement ◽  
Precipitation Sequence ◽  
Forming Process ◽  
Good Strength ◽  
6Xxx Series ◽  
Vickers Hardness Measurement

AlMgSi alloys (6XXX series) provide a good strength due to the precipitation of β” and β (Mg2Si) phases. They have also very good formability which is required for different forming process after appropriate heat treatments.This work was carried out to investigate the effect of the addition of copper and the excess of Si on the response of natural and artificial aging of two Al-Mg-Si alloys. The aging parameters on precipitation sequence of two Al-Mg-Si alloys with and without excess Si were studied by DSC, MET and Vickers hardness measurement. The combined effect of Cu, Fe and excess of Si was found to accelerate the precipitation of the hardening phases. The additions of copper to the AlMgSi refine the average of the grain size and have a greater hardening effect compared to the excess silicon addition.

Micro-Hardness and Morphology of LDPE Influenced by Beta Radiation

2014 ◽  
Vol 606 ◽  
pp. 253-256 ◽  
Author(s):  
Martin Ovsik ◽  
Petr Kratky ◽  
David Manas ◽  
Miroslav Manas ◽  
Michal Stanek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Hardness Test ◽  
Polymer Materials ◽  
Beta Radiation ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Depth Sensing ◽  
Surface Layers ◽  
Hardness Values ◽  
Different Doses

This article deals with the influence of different doses of Beta radiation to the structure and mico-mechanical properties of Low-density polyethylene (LDPE). Hard surface layers of polymer materials, especially LDPE, can be formed by radiation cross-linking by β radiation with doses of 33, 66 and 99 kGy. Material properties created by β radiation are measured by micro-hardness test using the DSI method (Depth Sensing Indentation). Individual radiation doses caused structural and micro-mechanical changes which have a significant effect on the final properties of the LDPE tested. The highest values of micro-mechanical properties were reached at radiation dose of 66 and 99 kGy, when the micro-hardness values increased by about 21%. The changes were examined and confirmed by X-ray diffraction.

Effect of Solution Treatment on Microstructures and Hardness of Mg-Gd-Y-Zr Alloy

2014 ◽  
Vol 937 ◽  
pp. 182-186
Author(s):  
Quan An Li ◽  
Lei Lei Chen ◽  
Wen Chuang Liu ◽  
Xing Yuan Zhang ◽  
Hui Zhen Jiang
Keyword(s):  
Vickers Hardness ◽  
Cast Alloy ◽  
Solution Treatment ◽  
Hardness Measurement ◽  
Solution Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solution Treated ◽  
Primary Particles ◽  
Zr Alloy

The influence of the solution treatment (at the temperature of 500-520°C for 4-12 h) on microstructures and mechanical properties of Mg-Gd-Y-Zr alloy was investigated by means of optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Vickers hardness measurement. The as-cast alloy contains a microstructure consisting of α-Mg matrix, Mg5Gd phase and Mg24Y5phase. With increasing solution temperature and time, the quantity of the primary particles (Mg5Gd and Mg24Y5) in the alloy continually decreased, and the degree of recrystallization gradually increased, which result in the gradual decrease of the Vickers hardness of the solution-treated alloys.

Olfactory Training Using Heavy and Light Weight Molecule Odors

Perception ◽  
2016 ◽  
Vol 46 (3-4) ◽  
pp. 343-351 ◽  
Author(s):  
Sophia C. Poletti ◽  
Elisabeth Michel ◽  
Thomas Hummel
Keyword(s):  
Molecular Weight ◽  
Olfactory Dysfunction ◽  
Light Weight ◽  
Short Term ◽  
Olfactory Loss ◽  
Short Term Exposure ◽  
Before And After ◽  
Phenyl Ethyl Alcohol ◽  
A Prospective Study ◽  
Olfactory Training

Background Repeated short-term exposure to odors is known to improve olfaction in patients with acquired olfactory dysfunction. The aim was to find out whether differences in molecular weight of odors used for olfactory training influences olfaction. We hypothesized a greater improvement following training with light weight molecule (LWM) odors. Methods A prospective study was performed in patients with posttraumatic (PTOL) and postviral olfactory loss (PVOL). Olfactory training was performed over a period of 5 months. One group ( n = 48) used four odors containing heavy weight molecules (HWM; >150 g/mol) and another ( n = 48) containing LWM (<150 g/mol). Olfaction was tested before and after the training using the Sniffin’ Sticks test. Results Olfactory training was associated with olfactory improvement, with the improvement in PVOL patients being three times greater than that seen in the PTOL group. Compared with LWM training, HWM training was associated with a significantly greater improvement in Phenyl Ethyl Alcohol (PEA) threshold scores in PVOL patients; however, no such improvement could be shown for other subtests or in PTOL patients. Conclusion Overall, training was associated with olfactory improvement. With the exception of threshold scores in PVOL, there were no significant differences between LWM and HWM groups.

scholarly journals Experimental Evaluation of Mechanical Properties of Friction Welded Dissimilar Steels under Varying Axial Pressures

2016 ◽  
Vol 66 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Amit Handa ◽  
Vikas Chawla
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Impact Strength ◽  
Failure Analysis ◽  
Friction Welding ◽  
Experimental Evaluation ◽  
Micro Hardness ◽  
Aisi 304 ◽  
Torsional Strength ◽  
Hardness Values

AbstractThe present study emphasizes on joints two industrially important materials AISI 304 with AISI 1021steels, produced by friction welding have been investigated. Samples were welded under different axial pressures ranging from 75MPa to 135MPa, at constant speed of 920rpm. The tensile strength, torsional strength, impact strength and micro hardness values of the weldments were determined and evaluated. Simultaneously the fractrography of the tensile tested specimens were carried out, so as to understand the failure analysis. It was observed that improved mechanical properties were noticed at higher axial pressures. Ductile failures of weldments were also observed at 120MPa and 135MPa axial pressures during fractography analysis.

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