Processing and Tensile Property of Nano Dispersed Al-Fe-(Mo, V, Zr) Bulk Alloy

2007 ◽  
Vol 26-28 ◽  
pp. 87-90
Author(s):  
Taek Kyun Jung ◽  
Mok Soon Kim ◽  
W.Y. Kim ◽  
Hyouk Chon Kwon ◽  
S. Yi
Keyword(s):  
Melt Spinning ◽  
Hot Extrusion ◽  
Grain Structure ◽  
Bulk Alloy ◽  
Average Grain Size ◽  
Spinning Process ◽  
20 Nm ◽  
Equiaxed Grain ◽  
Very High ◽  
Zr Alloy

The microstructures and mechanical properties of the bulk Al-Fe-(Mo, V, Zr) alloy produced by melt spinning process and subsequent hot extrusion at 693K in the extrusion ratio of 25 to 1 were investigated. TEM observation revealed an equiaxed grain structure with the average grain size of 200 nm for the extruded bulk alloy. Extremely fine dispersoids based on Al-Fe phases, Al-Fe-(Mo, V) phases and Al-Zr phases were observed to be distributed uniformly within grains and at grain boundaries. The size distribution of the binary Al-Fe and the Al-Fe-(Mo, V) phases were ranged from 20 nm to 50 nm, whereas the Al-Zr phase was less than 10 nm. The very high tensile strength of about 800MPa was achieved at room temperature for the extruded bulk alloy.

Effect of Warm Rolling on Microstructure and High Temperature Mechanical Behavior of a Nano-Structured Al-8Fe-2Mo-2V-1Zr Alloy

2005 ◽  
Vol 486-487 ◽  
pp. 411-414 ◽  
Author(s):  
Won Yong Kim ◽  
Jae Sung Park ◽  
Mok Soon Kim
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Elevated Temperatures ◽  
Hot Extrusion ◽  
Warm Rolling ◽  
Spray Forming ◽  
Grain Structure ◽  
Average Grain Size ◽  
Two Samples ◽  
Additional Process

Mechanical properties of a nano-structured Al-8Fe-2Mo-2V-1Zr alloy produced by spray forming and subsequent hot-extrusion at 420°C were investigated in terms of tensile test as a function of temperature. Warm rolling was adapted as an additional process to expect further refinement in microstructure. Well-defined equiaxed grain structure and finely distributed dispersoids with nano-scale in particle size were observed in the spray formed and hot extruded sample (as-received sample). The average grain size and particle size were measured to 500 nm and 50 nm, respectively. While it was found that warm rolling gives rise to precipitate fine dispersoids less than 10 nm without influencing the grain size of matrix phase, in the temperature range of RT∼150°C, distinguishable changes in ultimate tensile strength were not found between the as-received and warm-rolled samples. At elevated temperatures ranging from 350 to 550°C, warm-rolled sample showed a higher value of elongation than as-received one although similar values of elongation were observed between two samples at temperatures lower than 350°C.

scholarly journals The Production of Material with Ultrafine Grain Structure in Al-Zn Alloy in the Process of Rapid Solidification

2014 ◽  
Vol 14 (2) ◽  
pp. 57-62
Author(s):  
M. Szymaneka ◽  
B. Augustyn ◽  
D. Kapinos ◽  
S. Boczkal ◽  
J. Nowak
Keyword(s):  
Rapid Solidification ◽  
Melt Spinning ◽  
Hot Extrusion ◽  
High Strength ◽  
Strength Properties ◽  
Grain Structure ◽  
Ultrafine Grain ◽  
Plastic Working ◽  
Metal Treatment ◽  
Ultrafine Grain Structure

Abstract In the aluminium alloy family, Al-Zn materials with non-standard chemical composition containing Mg and Cu are a new group of alloys, mainly owing to their high strength properties. Proper choice of alloying elements, and of the method of molten metal treatment and casting enable further shaping of the properties. One of the modern methods to produce materials with submicron structure is a method of Rapid Solidification. The ribbon cast in a melt spinning device is an intermediate product for further plastic working. Using the technique of Rapid Solidification it is not possible to directly produce a solid structural material of the required shape and length. Therefore, the ribbon of an ultrafine grain or nanometric structure must be subjected to the operations of fragmentation, compaction, consolidation and hot extrusion. In this article the authors focussed their attention on the technological aspect of the above mentioned process and described successive stages of the fabrication of an AlZn9Mg2.5Cu1.8 alloy of ultrafine grain structure designated for further plastic working, which enables making extruded rods or elements shaped by the die forging technology. Studies described in the article were performed under variable parameters determined experimentally in the course of the alloy manufacturing process, including casting by RS and subsequent fragmentation.

scholarly journals Effect of Tool Rotational Speeds on Friction Stir Welded AA6082-T6 Aluminium Alloy Joints

2020 ◽  
Vol 9 (1) ◽  
pp. 62-67
Keyword(s):  
Tensile Strength ◽  
Aluminium Alloy ◽  
Rotational Speed ◽  
Mechanical Characteristics ◽  
Weld Zone ◽  
Grain Structure ◽  
Tool Rotational Speed ◽  
Friction Stir ◽  
Average Grain Size ◽  
Equiaxed Grain

In the current work, an attempt has been made to investigate the effect of tool rotational speed on microstructural and mechanical properties of friction stir welded AA6082-T6 aluminium alloy. Four different tool rotational speeds such as 500, 700, 900 and 1100 rpm were used to produce the joints while keeping the other process parameters constant. The tool used to fabricate the welded samples was tungsten carbide with straight cylindrical pin profile. The microstructural properties were examined using an optical and scanning electron microscope and found that the 700 rpm produced joint showed equiaxed grain structure with 14.3 µm average grain size. The mechanical characteristics such as tensile strength, impact strength and microhardness were evaluated and found the highest tensile strength of 265 MPa, impact energy of 10 J and micro hardness of 76 HV in the weld zone for the sample prepared with 700 rpm tool rotational speed. The fractographic studies were also carried out to study the mode of failure.

Simulation of the Grain Structure Evolution of a Mg-Al-Ca-Based Alloy during Hot Extrusion Using the Cellular Automation Method

2011 ◽  
Vol 491 ◽  
pp. 265-272 ◽  
Author(s):  
L. Li ◽  
F. He ◽  
X. Liu ◽  
Yan Lou ◽  
Jie Zhou ◽  
...  
Keyword(s):  
Hot Extrusion ◽  
Extrusion Process ◽  
Grain Structure ◽  
Structure Evolution ◽  
Compression Tests ◽  
3D Fem ◽  
Parameter Recovery ◽  
Cellular Automation ◽  
Average Grain Size ◽  
Ram Speed

In the present study, the evolution of the grain structure of a Mg-Al-Ca-based alloy during hot extrusion was simulated with the cellular automation method. The Laasraoui-Jonas microstructure model was used to describe the dislocation evolution inside crystallites during dynamic recrystallization. The parameters in the Laasraoui-Jonas model, such as the hardening parameter, recovery parameter and material constants, were determined from the flow stress-strain data obtained from hot compression tests using a Gleeble-1500 thermomechanical simulator. The extrusion process was simulated using a DEFORM 3D FEM code. The influence of ram speed on grain structure evolution was analyzed. It was found that the average grain size increases with increasing ram speed. Good agreements between the predicted and observed grain structures were achieved.

Substructure Development in Rapidly Solidified B2-Type TiCo Ribbons

2005 ◽  
Vol 475-479 ◽  
pp. 849-852 ◽  
Author(s):  
Kyosuke Yoshimi ◽  
Minseok Sung ◽  
Sadahiro Tsurekawa ◽  
Akira Yamauchi ◽  
Ryusuke Nakamura ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Dislocation Density ◽  
Rapid Solidification ◽  
Melt Spinning ◽  
Grain Structure ◽  
Second Phase ◽  
Rapidly Solidified ◽  
Equiaxed Grain

Substructure development through aging and annealing treatments was studied for rapidly solidified TiCo ribbons using TEM. In as-spun ribbons, equiaxed grain structure was developed and its crystal structure was B2-ordered immediately after melt-spinning, while a small amount of fine precipitates existed as second phase. Some grains were dislocation-free but others contained a certain amount of curved or helical dislocations and loops. The dislocation density in the ribbons annealed at 700 °C for 24 h was obviously higher than those in the as-spun ribbons and the ribbons aged at 200 °C for 100 h. The increase of the dislocation density in the annealed ribbons would result from the absorption of excess vacancies. Therefore, the obtained results indicated that a large amount of supersaturated thermal vacancies were retained in TiCo as-spun ribbons by the rapid solidification.

Microstructure and Compression Properties of Al-8Fe-2Mo-2V-1Zr Alloys Produced by Extrusion of Melt-Spun Powders

2007 ◽  
Vol 124-126 ◽  
pp. 1521-1524 ◽  
Author(s):  
Taek Kyun Jung ◽  
T.J. Sung ◽  
Mok Soon Kim ◽  
W.Y. Kim
Keyword(s):  
Melt Spinning ◽  
Elevated Temperatures ◽  
Hot Extrusion ◽  
High Yield ◽  
Compression Properties ◽  
Nano Crystalline ◽  
Average Grain Size ◽  
Multi Phase ◽  
Equiaxed Grains ◽  
Bulk Alloys

Bulk Al-8Fe-2Mo-2V-1Zr (wt.%) alloys were produced by melt spinning which can give rise to develope a nano crystalline structure in terms of rapid cooling and subsequent hot extrusion. The bulk alloys exhibited multi-phase microstructures consisting of ultra fine equiaxed grains with the average grain size of 100nm and a fine intermetallic Al-Fe, Al-V and Al-Zr based phase having less than 50nm in particle size. From compression test, it was revealed that the bulk alloys have very high yield strength at both room temperature (942MPa) and elevated temperatures (651MPa at 473K, 500MPa at 573K, respectively).

Fabrication and Properties of High Strength Al-8Fe-2Mo-2V-1Zr Alloy Produced by Melt Spinning Techniques

2006 ◽  
Vol 510-511 ◽  
pp. 854-857 ◽  
Author(s):  
Taek Kyun Jung ◽  
Dong Suk Lee ◽  
Mok Soon Kim ◽  
Won Yong Kim
Keyword(s):  
Particle Size ◽  
Yield Strength ◽  
Melt Spinning ◽  
Room Temperature ◽  
Intermetallic Phase ◽  
Hot Extrusion ◽  
High Strength ◽  
Extrusion Temperature ◽  
Grain Structure ◽  
Melt Spun

High strength Al-8Fe-2Mo-2V-1Zr (wt.%) alloys fabricated by a melt spinning and a hot extrusion process were produced to correlate the microstructure and mechanical property. Melt spun ribbon prepared by single roll melt spinner showed a cellular structure with an average size of 10nm and Al-Fe based intermetallic dispersoid of less than 10nm in particle size. The melt spun ribbon obtained was then pulverized to make a powder shape followed by hot extrusion at 648K, 673K, 723K and 773K in extrusion ratio of 5 to 1, respectively. Equiaxed grain structure containing Al-Fe based intermetallic phase was observed in all extruded specimens. According to increasing extrusion temperature, the grain size increased and particle size of intermetallic dispersoid. The lattice parameter increased from 0.4051nm to 0.4059 nm with increasing extrusion temperature from 648K to 773K, those values were larger than that obtained in pure Al (0.4049nm). Yield strength of the specimen extruded at 648K measured to 956MPa at room temperature, 501MPa at 573K and 83MPa at 773K, respectively. With increasing extrusion temperature yield strength decreased significantly at room temperature and even in the intermediate temperature range, while no noticeable difference in yield strength was observed at 773K.

Producing Ultrafine Grain Structure in AZ91 Magnesium Alloy Cast by Rapid Solidification

2014 ◽  
Vol 59 (1) ◽  
pp. 317-321 ◽  
Author(s):  
M. Szymanek ◽  
B. Augustyn ◽  
D. Kapinos ◽  
S. Boczkal ◽  
J. Nowak
Keyword(s):  
Magnesium Alloy ◽  
Rapid Solidification ◽  
Melt Spinning ◽  
Hot Extrusion ◽  
Solidification Process ◽  
Grain Structure ◽  
Ultrafine Grain ◽  
Az91 Magnesium Alloy ◽  
Az91 Magnesium ◽  
Ultrafine Grain Structure

Abstract The paper presents the technological aspect of the process of casting, crushing and plastic consolidation of semi-finished products from magnesium alloy. The aim of this study was to produce by the rapid solidification process a magnesium alloy from the MgAl9Zn1 family in the form of ribbons with ultrafine grain structure. The material cast in the melt spinning device was next crushed and subjected to the operation of cold consolidation and hot extrusion. The paper presents different stages of the process, including initial characterisation of the obtained material.

Processing of Wrought Magnesium Alloys to Produce Small Tubes for Biomedical Applications: Investigation about the Extrusion Process by a Laboratory Test Rig

2011 ◽  
Vol 491 ◽  
pp. 75-80
Author(s):  
Qiang Ge ◽  
Maurizio Vedani
Keyword(s):  
Biomedical Applications ◽  
Hot Extrusion ◽  
Extrusion Process ◽  
Grain Structure ◽  
Outer Diameter ◽  
Test Rig ◽  
Inner Diameter ◽  
Ebsd Technique ◽  
Equiaxed Grain ◽  
Basal Type

Two commercial ZM21 and AZ31B alloys were extruded into small-size tubes at 410°C and strain rate 2.78·10-3 s-1 by a laboratory hot-extrusion system. The series of tubes, with outer diameter in the range of 8-4 mm and inner diameter from 6 to 3 mm were investigated considering microstructure and texture analysis. The tubes featured a homogeneous and refined equiaxed grain structure since dynamic recrystallization was clearly observed during the extrusion process. A typical ‘basal’ type texture was detected in extruded tubes by using EBSD technique.

scholarly journals Microstructures of a SiC–ZrC Ceramic Fiber Derived from a Polymeric Precursor

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2142 ◽  
Author(s):  
Min Ge ◽  
Xiaoxu Lv ◽  
Hao Zhang ◽  
Shouquan Yu ◽  
Zhenxi Lu ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Melt Spinning ◽  
Zirconium Carbide ◽  
Temperature Treatment ◽  
Free Carbon ◽  
Ceramic Fiber ◽  
High Temperature Treatment ◽  
Average Grain Size ◽  
Electron Beam Curing ◽  
20 Nm

Continuous ceramic fiber comprising silicon carbide–zirconium carbide (SiC–ZrC) binary phases was obtained through melt spinning, electron-beam curing and pyrolysis of a pre-ceramic precursor of polyzirconocenecarbosilanes (PZCS). After pyrolysis and heat treatment, ZrC particles with mean diameters of 15–20 nm were formed and homogeneously dispersed in a matrix of fine crystalline β-SiC with an average grain size of 6–10 nm. Concentration of Zr in the fiber varies from 14.88% to 17.45% by mass. Fibers consisting of near-stoichiometric ZrC and SiC with little free carbon can be obtained through pyrolysis decarbonization of the as-cured fiber in hydrogen from room temperature to 1000 °C, and subsequently heat treatment in argon up to 1600 °C for 1 h. High-temperature treatment of these amorphous inorganic fibers leads to crystallization of the binary phases of β-SiC and ZrC. The removal of free carbon under hydrogen results in more rapid growth of β-SiC and ZrC crystals, in which obvious aggregation of the dispersed ZrC particles among the continuous β-SiC matrix can be ascribed to a fast migration of Zr cation.

Sign in / Sign up

Export Citation Format

Share Document