scholarly journals Effect of ECAP on the Microstructure and Mechanical Properties of a Rolled Mg-2Y-0.6Nd-0.6Zr Magnesium Alloy

Crystals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 586 ◽  
Author(s):  
Shi ◽  
Li ◽  
Hu ◽  
Tan ◽  
Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Room Temperature ◽  
High Strength ◽  
Electron Backscattered Diffraction ◽  
Bar Rolling ◽  
Fine Grained ◽  
Angular Pressing ◽  
Microstructure And Mechanical Properties ◽  
Average Grain Size

A fine-grained Mg-2Y-0.6Nd-0.6Zr alloy was processed by bar-rolling and equal-channel angular pressing (ECAP). The effect of ECAP on the microstructure and mechanical properties of rolled Mg-2Y-0.6Nd-0.6Zr alloy was investigated by optical microscopy, scanning electron microscopy, electron backscattered diffraction and a room temperature tensile test. The results show that the Mg-2Y-0.6Nd-0.6Zr alloy obtained high strength and poor plasticity after rolling. As the number of ECAP passes increased, the grain size of the alloy gradually reduced and the texture of the basal plane gradually weakened. The ultimate tensile strength of the alloy first increased and then decreased, the yield strength gradually decreased, and the plasticity continuously increased. After four passes of ECAP, the average grain size decreased from 11.2 µm to 1.87 µm, and the alloy obtained excellent comprehensive mechanical properties. Its strength was slightly reduced compared to the as-rolled alloy, but the plasticity was greatly increased.

Effects of Thermo-Mechanical Process on the Microstructure and Mechanical Properties of Low Carbon HSLA Steels

2006 ◽  
Vol 15-17 ◽  
pp. 786-791 ◽  
Author(s):  
J.S. Kang ◽  
Y. Huang ◽  
C.W. Lee ◽  
Chan Gyung Park
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Cooling Rate ◽  
High Strength ◽  
Nucleation Site ◽  
Polygonal Ferrite ◽  
Low Alloy Steels ◽  
Low Carbon ◽  
Microstructure And Mechanical Properties ◽  
Average Grain Size

Effects of deformation at austenite region and cooling rate on the microstructure and mechanical properties of low carbon (0.06 wt. % C) high strength low alloy steels have been investigated. Average grain size decreased and polygonal ferrite transformation promoted with increasing deformation amount at austenite region due to increase of ferrite nucleation site. Microstructure was also influenced by cooling rate resulting in the development of a mixture of fine polygonal ferrite and acicular ferrite at 10°C/s cooling rate. Discontinuous yielding occurred in highly deformed specimen due to the formation of polygonal ferrite. However, small grain size of highly deformed specimen caused lower ductile-to-brittle transition temperature than slightly deformed specimen.

Microstructure and Mechanical Properties of AA5483 after Combination of ECAP and Hydrostatic Extrusion SPD Processes

2014 ◽  
Vol 59 (1) ◽  
pp. 163-166 ◽  
Author(s):  
M. Kulczyk ◽  
J. Skiba ◽  
W. Pachla
Keyword(s):  
Mechanical Properties ◽  
Salt Water ◽  
True Strain ◽  
High Strength ◽  
Tensile Tests ◽  
Hydrostatic Extrusion ◽  
Angular Pressing ◽  
Microstructure And Mechanical Properties ◽  
Average Grain Size ◽  
Marine Applications

Abstract Al-Mg alloys of the 5xxx series are strain hardenable and have moderately high strength, excellent corrosion resistance even in salt water, and very high toughness even at cryogenic temperatures to near absolute zero, which makes them attractive for a variety of applications, e.g. in systems exploited at temperatures as low as -270°C, and marine applications. The present study is concerned with the effect of a combination of 2 processes, which generate serve plastic deformation (SPD), equal channel angular pressing (ECAP) and hydrostatic extrusion (HE), on the microstructure and mechanical properties of an alloy that contain Al and Mg. The alloy was subjected to multi-pass ECAP followed by cumulative HE with a total true strain of 5.9. The microstructure of SPD samples was evaluated by transmission and scanning electron microscopy. The mechanical properties were determined by tensile tests and microhardness measurements. The combination of the two processes gave a uniform nanostructure with an average grain size of 70nm. The grain refinement taking place during the SPD processing resulted in the increase of the mechanical strength by 165% (YS) with respect to that of the material in the as- received state. The experiments have shown that the combination of HE and ECAP permits producing homogeneous nanocrystalline materials of large volumes.

The Influence of Texture and Grain Size on Compressive Deformation Behavior of Pure Mg through Equal-Channel Angular Processing

2010 ◽  
Vol 667-669 ◽  
pp. 385-390
Author(s):  
Ji Zhong Li ◽  
Hua Ding ◽  
Xiao Lin Wu ◽  
Wei Xu ◽  
Kenong Xia
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Deformation Behavior ◽  
Room Temperature ◽  
High Strength ◽  
Grain Structure ◽  
Large Plastic Deformation ◽  
Angular Pressing ◽  
Equal Channel Angular Processing ◽  
Single Temperature

Multi-pass of equal channel angular pressing (ECAP) at a single temperature as low as room temperature from 200 °C were measured using electronic back scatter diffraction (EBSD). The effect of texture and grain size on mechanical properties was investigated to realize the strengthening and large plastic deformation mechanism. A room temperature ECAP with multi-pass procedure is effective to product high strength and large plastic Mg, as a result of submicron grain structure and texture strengthening.

scholarly journals Experimental and Numerical Investigation of the ECAP Processed Copper: Microstructural Evolution, Crystallographic Texture and Hardness Homogeneity

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 607
Author(s):  
A. I. Alateyah ◽  
Mohamed M. Z. Ahmed ◽  
Yasser Zedan ◽  
H. Abd El-Hafez ◽  
Majed O. Alawad ◽  
...  
Keyword(s):  
Grain Size ◽  
Equal Channel Angular Pressing ◽  
Cross Section ◽  
Room Temperature ◽  
Pure Copper ◽  
High Density ◽  
Ecap Processing ◽  
Heterogeneous Distribution ◽  
Angular Pressing ◽  
Average Grain Size

The current study presents a detailed investigation for the equal channel angular pressing of pure copper through two regimes. The first was equal channel angular pressing (ECAP) processing at room temperature and the second was ECAP processing at 200 °C for up to 4-passes of route Bc. The grain structure and texture was investigated using electron back scattering diffraction (EBSD) across the whole sample cross-section and also the hardness and the tensile properties. The microstructure obtained after 1-pass at room temperature revealed finer equiaxed grains of about 3.89 µm down to submicrons with a high density of twin compared to the starting material. Additionally, a notable increase in the low angle grain boundaries (LAGBs) density was observed. This microstructure was found to be homogenous through the sample cross section. Further straining up to 2-passes showed a significant reduction of the average grain size to 2.97 µm with observable heterogeneous distribution of grains size. On the other hand, increasing the strain up to 4-passes enhanced the homogeneity of grain size distribution. The texture after 4-passes resembled the simple shear texture with about 7 times random. Conducting the ECAP processing at 200 °C resulted in a severely deformed microstructure with the highest fraction of submicron grains and high density of substructures was also observed. ECAP processing through 4-passes at room temperature experienced a significant increase in both hardness and tensile strength up to 180% and 124%, respectively.

Microstructures and Mechanical Properties of AZ61 Mg Alloy Processed by Equal Channel Angular Pressing

2012 ◽  
Vol 468-471 ◽  
pp. 2124-2127 ◽  
Author(s):  
Shao Feng Zeng ◽  
Kai Huai Yang ◽  
Wen Zhe Chen
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Equal Channel Angular Pressing ◽  
Uniform Elongation ◽  
Considerable Decrease ◽  
Angular Pressing ◽  
Az61 Magnesium Alloy ◽  
Average Grain Size ◽  
Microstructures And Mechanical Properties ◽  
Bimodal Grain Size

Equal channel angular pressing (ECAP) was applied to a commercial AZ61 magnesium alloy for up to 8 passes at temperatures as low as 473K. Microstructures and mechanical properties of as-received and ECAP deformed samples were investigated. The microstructure was initially not uniform with a “bimodal” grain size distribution but became increasingly homogeneous with further ECAP passes and the average grain size was considerably reduced from over 26 μm to below 5 μm. The ultimate tensile strength (UTS) decreases clearly after one pass, but increases significantly up to two passes, and then continuously slowly decreases up to six passes, and again increases slightly up to eight passes. In contrast, the uniform elongation increased significantly up to 3 passes, followed by considerable decrease up to 8 passes. These observations may be attributed to combined effects of grain refinement and texture development.

scholarly journals Influence of Steel Grain Size on Residual Stress in Grinding Processing

2010 ◽  
Vol 638-642 ◽  
pp. 2389-2394 ◽  
Author(s):  
Masahide Gotoh ◽  
Katsuhiro Seki ◽  
M. Shozu ◽  
Hajime Hirose ◽  
Toshihiko Sasaki
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
Grain Size ◽  
Stress State ◽  
Mechanical Grinding ◽  
Fine Grained ◽  
Residual Stress State ◽  
Analysis Methods ◽  
Average Grain Size ◽  
Fine Grained Steels

The fine-grained rolling steels NFG600 and the conventional usual rolling steels SM490 were processed by sand paper polishing and mechanical grinding to compare the residual stress generated after processing. The average grain size of NFG600 and SM490 is 3 μm and 15μm respectively. Therefore improvement of mechanical properties for such fine-grained steels is expected, it is important to understand the residual stress state of new fine-grained materials with processing. In this study, multi axial stresses of two kinds of specimens after polishing and grinding were measured by three kinds of analysis methods including cos-ψ method. As a result, as for σ33, the stress of NFG was compression, though that of SM490 was tension.

scholarly journals STRUCTURE AND PROPERTIES OF AZ31 MAGNESIUM ALLOY AFTER COMBINATION OF HOT EXTRUSION AND ECAP

2017 ◽  
Vol 23 (3) ◽  
pp. 222 ◽  
Author(s):  
Ondřej Hilšer ◽  
Stanislav Rusz ◽  
Wojciech Maziarz ◽  
Jan Dutkiewicz ◽  
Tomasz Tański ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Magnesium Alloy ◽  
Hot Extrusion ◽  
Az31 Magnesium Alloy ◽  
Initial State ◽  
Fine Grained ◽  
Angular Pressing ◽  
Ecap Process ◽  
Average Grain Size ◽  
Fine Grained Structure

<p>Equal channel angular pressing (ECAP) method was used for achieving very fine-grained structure and increased mechanical properties of AZ31 magnesium alloy. The experiments were focused on the, in the initial state, hot extruded alloy. ECAP process was realized at the temperature 250°C and following route Bc. It was found that combination of hot extrusion and ECAP leads to producing of material with significantly fine-grained structure and improves mechanical properties. Alloy structure after the fourth pass of ECAP tool with helix matrix 30° shows a fine-grained structure with average grain size of 2 µm to 3 µm and high disorientation between the grains. More experimental results are discussed in this article.</p>

Effect of Hot Processing on Mircrostructure and Properties of Flat Billets of TA15 Titanium Alloy

2021 ◽  
Vol 1016 ◽  
pp. 906-910
Author(s):  
Xin Hua Min ◽  
Cheng Jin
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Titanium Alloy ◽  
High Temperature ◽  
Room Temperature ◽  
High Strength ◽  
Slow Cooling ◽  
Microstructure And Mechanical Properties ◽  
Ta15 Titanium Alloy ◽  
The Ideal

In this paper,effect of the different forging processes on the microstructure and mechanical properties of the flat flat billets of TA15 titanium alloy was investigated.The flat billiets of 80 mm×150 mm×L sizes of TA15 titanium alloy are produced by four different forging processes.Then the different microstrure and properties of the flat billiets were obtained by heat treatment of 800 °C~850 °C×1 h~4h.The results show that, adopting the first forging temperature at T1 °C、slow cooling and the second forging temperature at T2°C 、quick cooling, the primary αphases content is just 10%, and there are lots of thin aciculate phases on the base. This microstructure has both high strength at room temperature and high temperature, while the properties between the cross and lengthwise directions are just the same. So the hot processing of the first forging temperature at T1 °C、slow cooling and the second forging temperature at T2°C 、quick cooling is choosed as the ideal processing for production of aircraft frame parts.

Effect of Fast Annealing on Microstructure and Mechanical Properties of Non-Oriented Al-Si Low C Electrical Steels

2007 ◽  
Vol 560 ◽  
pp. 29-34 ◽  
Author(s):  
Emmanuel Gutiérrez C. ◽  
Armando Salinas-Rodríguez ◽  
Enrique Nava-Vázquez
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Room Temperature ◽  
Tensile Tests ◽  
Rate Of Change ◽  
Uniaxial Tensile ◽  
Electrical Steels ◽  
Offset Yield Strength ◽  
Microstructure And Mechanical Properties ◽  
Increasing Temperature

The effects of heating rate and annealing temperature on the microstructure and mechanical properties of cold rolled Al-Si, low C non-oriented electrical steels are investigated using SEM metallography and uniaxial tensile tests. The experimental results show that short term annealing at temperatures up to 850 °C result in microstructures consisting of recrystallized ferrite grains with sizes similar to those observed in industrial semi-processed strips subjected to long term batch annealing treatments. Within the temperature range investigated, the grain size increases and the 0.2% offset yield strength decreases with increasing temperature. It was observed that the rate of change of grain size with increasing temperature increases when annealing is performed at temperatures greater than Ac1 (~870 °C). This effect is attributed to Fe3C dissolution and rapid C segregation to austenite for annealing temperatures within the ferrite+austenite phase field. This leads to faster ferrite growth and formation of pearlite when the steel is finally cooled to room temperature. The presence of pearlite at room temperature decreases the ductility of samples annealed at T > Ac1.

Sign in / Sign up

Export Citation Format

Share Document