Bond Strength of Ultrafine Grained Zr Fabricated by Accumulative Roll Bonding

2008 ◽  
Vol 584-586 ◽  
pp. 243-248 ◽  
Author(s):  
Ling Jiang ◽  
Maria Teresa Pérez-Prado ◽  
Oscar A. Ruano ◽  
M.E. Kassner
Keyword(s):  
Grain Size ◽  
Shear Strength ◽  
Bond Strength ◽  
Fracture Strength ◽  
Accumulative Roll Bonding ◽  
Shear Fracture ◽  
High Ductility ◽  
Roll Bonding ◽  
Ultrafine Grained

The bond strength of ultrafine grained Zr with a grain size of 0.4 µm, fabricated by accumulative roll bonding (ARB), was assessed. The shear strength of the bond was estimated to be about 20% of the shear fracture strength of the as processed metal, a ratio significantly higher than that found in other materials processed by similar methods. The favorable degree of bonding achieved is attributed to the high ductility of Zr as well as to the high reductions used during the ARB process.

Superplasticity in Ultrafine Grained Magnesium Alloy AZ31 Prepared by Accumulative Roll Bonding

2007 ◽  
Vol 551-552 ◽  
pp. 249-254 ◽  
Author(s):  
Qing Feng Wang ◽  
X.P. Xiao ◽  
X.J. Chen ◽  
W. Chen
Keyword(s):  
Grain Size ◽  
Magnesium Alloy ◽  
Strain Rate ◽  
Accumulative Roll Bonding ◽  
Superplastic Deformation ◽  
Grain Boundary Sliding ◽  
Alloy Sheet ◽  
Roll Bonding ◽  
Magnesium Alloy Sheet ◽  
Ultrafine Grained

In this paper, an ultra-fine grained AZ31 magnesium alloy sheet with grain size less than 3μm was generated by three-run accumulative roll bonding of as cast alloy at a deformation temperature of 350°C and a reduction of 80% for each pass. The microstructures on the different ARB stages were observed and superplasticity examination in the ultrafine grained AZ31 alloy were carried out at a fixed temperature of 300°C and varied strain rate ranging from 10-4 to 10-1 s-1. It is indicated that significant grain refinement was mainly achieved in the first run and gradual uniformity of grain size in the next by continuous dynamic recrystalization. Besides, a superplastic deformation with a moderate elongation-to-fracture of 316% was obtained at a strain rate of 10-2 s-1 indicating a low temperature and high strain rate superplasticity, while a maximum elongation-to-fracture of 562% at10-4 s-1. The strain rate sensitivity exponent as high as of 0.34-0.41 implies the dominant role of grain boundary sliding in superplastic deformation at strain rate ranging from 10-3 to 10-2 s-1. The results indicate a possible approach to produce magnesium alloy sheet with fine grain and excellent deep drawing workability.

Mechanical Properties and Aging Behavior of Ultrafine Grained Al-Ag Alloy Fabricated by Accumulative Roll-Bonding

2014 ◽  
Vol 794-796 ◽  
pp. 851-856
Author(s):  
Tadashiege Nagae ◽  
Nobuhiro Tsuji ◽  
Daisuke Terada
Keyword(s):  
Mechanical Properties ◽  
Grain Refinement ◽  
Accumulative Roll Bonding ◽  
Precipitation Hardening ◽  
Tensile Elongation ◽  
Solution Treatment ◽  
High Strength ◽  
Subsequent Aging ◽  
Roll Bonding ◽  
Ultrafine Grained

Accumulative roll-bonding (ARB) process is one of the severe plastic deformation processes for fabricating ultrafine grained materials that exhibit high strength. In aluminum alloys, aging heat treatment has been an important process for hardening materials. In order to achieve good mechanical properties through the combination of grain refinement hardening and precipitation hardening, an Al-4.2wt%Ag binary alloy was used in the present study. After a solution treatment at 550°C for 1.5hr, the alloy was severely deformed by the ARB process at room temperature (RT) up to 6 cycles (equivalent strain of 4.8). The specimens ARB-processed by various cycles (various strains) were subsequently aged at 100, 150, 200, 250°C, and RT. The hardness of the solution treated (ST) specimen increased by aging. On the other hand, hardness of the ARB processed specimen decreased after aging at high temperatures such as 250°C. This was probably due to coarsening of precipitates or/and matrix grains. The specimen aged at lower temperature showed higher hardness. The maximum harnesses achieved by aging for the ST specimen, the specimens ARB processed by 2 cycles, 4 cycles and 6 cycles were 55HV, 71HV, 69HV and 65HV, respectively. By tensile tests it was shown that the strength increased by the ARB process though the elongation decreased significantly. However, it was found that the tensile elongation of the ARB processed specimens was improved by aging without sacrificing the strength. The results suggest that the Al-Ag alloy having large elongation as well as high strength can be realized by the combination of the ARB process for grain refinement and the subsequent aging for precipitation hardening.

ACCUMULATIVE ROLL BONDING OF AZ31 MAGNESIUM ALLOY

2008 ◽  
Vol 22 (18n19) ◽  
pp. 2833-2939 ◽  
Author(s):  
S. M. FATEMI-VARZANEH ◽  
A. ZAREI-HANZAKI ◽  
M. HAGHSHENAS
Keyword(s):  
Grain Size ◽  
Magnesium Alloy ◽  
Accumulative Roll Bonding ◽  
Az31 Alloy ◽  
Thickness Reduction ◽  
Az31 Magnesium Alloy ◽  
Total Strain ◽  
Roll Bonding ◽  
Fine Grain

This work conducted to investigate the effects of accumulative roll bonding (ARB) method on achieving the ultra-fine grain microstructure in AZ31 alloy. Accordingly, a number of ARB routes at 400°C, applying thickness reductions per pass of 35%, 55%, and 85% were performed. The results indicate that both the final grain size and the degree of bonding have been dictated by the thickness reduction per pass. The larger pass reductions promote a higher degree of bonding. Increasing the total strain stimulates the formation of a more homogeneous ultra fine grain microstructure.

Microstructure and Aging Behavior of Al-0.2wt%Zr Alloy Heavily Deformed by ARB Process

2008 ◽  
Vol 584-586 ◽  
pp. 728-733 ◽  
Author(s):  
Takatoshi Sato ◽  
Daisuke Terada ◽  
Nobuhiro Tsuji
Keyword(s):  
Grain Size ◽  
Microstructural Evolution ◽  
Coarse Grain ◽  
Aging Behavior ◽  
Roll Bonding ◽  
Solution Treated ◽  
Ultrafine Grained ◽  
Mean Grain Size ◽  
Treated State ◽  
Zr Alloy

An Al-0.2wt%Zr alloy was severely deformed up to a strain of 8.0 by accumulative roll bonding (ARB) process, started from the solution-treated state. The microstructural evolution during ARB and its aging behavior were investigated. With increasing the number of ARB cycles, Vickers hardness of the specimens increased and reached to a constant value. The microstructural evolution during the ARB could be understood in terms of grain subdivision. The ultrafine grained (UFG) materials whose mean grain size was 0.4 -m were obtained by 10-cycle ARB process. In aging of the ARB processed specimens at high temperatures above 673K, the UFG microstructures quickly coarsened. On the other hand, it was suggested that the precipitation behaviors of the ARB specimen at 623K were quite unique and completely different from those of the conventionally solution-treated material with coarse grain size.

scholarly journals An Experimental Study of Fracture Toughness for Nano/Ultrafine Grained Al5052/Cu Multilayered Composite Processed by Accumulative Roll Bonding

2018 ◽  
Vol 140 (10) ◽  
Author(s):  
D. Rahmatabadi ◽  
B. Mohammadi ◽  
R. Hashemi ◽  
T. Shojaee
Keyword(s):  
Fracture Toughness ◽  
Stress Fracture ◽  
Plane Stress ◽  
Accumulative Roll Bonding ◽  
Uniaxial Tensile ◽  
Roll Bonding ◽  
Multilayered Composite ◽  
Maximum Value ◽  
Ultrafine Grained ◽  
Pure Cu

In this study, ultrafine grained Al5052/Cu multilayered composite has been produced by accumulative roll bonding (ARB) and fracture properties have been studied using plane stress fracture toughness. The fracture toughness has been investigated for the unprocessed specimens, primary sandwich and first, second, and third cycles of ARB process by ASTM E561 and compact tension (CT) specimens. Also, the microstructure and mechanical properties have been investigated using optical microscopy, scanning electron microscopy, uniaxial tensile tests, and microhardness measurements. The value of plane stress fracture toughness for the ultrafine grained Al5052/Cu composite increased by increasing the number of ARB cycles, continuously from the primary sandwich to end of the third cycle. The maximum value of 59.1 MPa m1/2 has been obtained that it is about 2.77 and 4.05 more than Al5052 and pure Cu (unprocessed specimens). This phenomenon indicated that ARB process and the addition of copper to aluminum alloy could increase the value of fracture toughness to more than three times. The results showed that by increasing the ARB cycles, the thickness of copper layers reduced and after the fifth cycle, the excellent uniformity of Cu layers achieved. By increasing the number of ARB cycles, the microhardness of both aluminum and copper layers have been significantly increased. The tensile strength of the sandwich has been enhanced continually, and the maximum value of 566.5 MPa has been achieved.

Review on Accumulative Roll Bonding (ARB) Techniques for Improving the Mechanical Properties of Multi-Layered Materials

2020 ◽  
Vol 979 ◽  
pp. 84-88
Author(s):  
A. Arun ◽  
Lakshmanan Poovazhgan
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Accumulative Roll Bonding ◽  
Nanocrystalline Structure ◽  
Hardness Test ◽  
Roll Bonding ◽  
Transmission Electron ◽  
Ultrafine Grained ◽  
Materials Used ◽  
Number Of Passes

Accumulative Roll Bonding (ARB) is one among the techniques in Severe Plastic Deformation (SPD) which is used to produce ultrafine grains and nanocrystalline structure in the materials used. Tensile test, micro hardness test, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and bending tests are the various tests carried out to understand the grain refinement of ARB materials. ARB is carried out in homogenous and heterogeneous materials to bring out the useful applications of ultrafine grained materials. ARB process mainly carried out in room, warm and hot temperature. The variations in the structure of the material are obtained by changing the load applied on the roller and by increasing the number of passes. This review paper brings out how the mechanical properties of the materials are improved by ARB process

Sign in / Sign up

Export Citation Format

Share Document