Microstructures and Properties of Twin-Roll Casting 7050 Aluminum Alloy Strip

2013 ◽  
Vol 652-654 ◽  
pp. 2397-2403 ◽  
Author(s):  
Chun Fu Li ◽  
Hong Bin Wang ◽  
Fan Lei Meng ◽  
Hong Yang Zhao

In this study, 7050 aluminum alloy strip was produced using the twin-roll casting technique. Microstructures and properties of the cast-rolling 7050 aluminum alloy were investigated by means of optical microscope (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Vickers hardness test. The results indicate that microstructures of cast-rolling 7050 alloy strip are inhomogeneous on the cross section. From the edge to the center, the size of grain decreases gradually and becomes more homogeneous, showing a transition from dendrite grains to equiaxed grains. There are undissolved second phase particles in grains and at grain boundaries. And the dendrite grains and second phase particles can be reduced by solution treatment, and the hardness of the cast-rolling strip can be improved by aging treatment.

2013 ◽  
Vol 652-654 ◽  
pp. 2427-2431 ◽  
Author(s):  
Xin Su ◽  
G M Xu ◽  
Y H Feng

In this paper, the effect of magnetostatic field on the microstructure and microsegregation of 7075 aluminum alloy strip by twin-roll casting is researched , and the result shows that when no electromagnetic field is applied during the process of roll-casting , the microstructure of 7075 strip is most composed of coarse columnar and dendritic crystal , the direction of grains is equal to roll-casting direction. When the magnetostatic field with 0.13T intensity is applied during the twin-roll casting, the microstructural of strip becomes uniform ,refined and equiaxed at the central zone of strip, and the dendritic crystal at the surficial is disordered and refined significantly.


Author(s):  
Bowen Wei ◽  
Tao Jiang ◽  
Shiju Li ◽  
Youyun Zhang ◽  
Guangming Xu ◽  
...  

Abstract The effect of superheat melt treatment(SMT) on microstructure and properties of Al-Mg-Si alloy fabricated by twin roll casting(TRC) was analyzed using optical microscope, scanning electron microscopy, emission electron probe micro analyzer and transmission electron microscopy. SMT increased the subcooling degree of melt during TRC. The solidification microstructure with high dendrite density and small dendrite spacing was obtained. The second phase was evenly distributed between dendrites and the solute concentration gradient was decreased. Intergranular solute aggregation caused by Reynolds’ dilatancy in TRC slab was effectively suppressed. The homogeneous solute distribution of TRC slab with SMT can be realized by short-time homogenization heat treatment. The size of insoluble particles was greatly reduced. The complete decomposition of non-equilibrium eutectic phase increased the solute concentration in α-Al, which promoted the precipitation of precipitates during aging heat treatment. The tensile strength and yield strength of T6 slab were improved, while the uniform elongation are almost not decreased. The strength and uniform of slab in T4P state were both improved. The obtained results can help further shorten the production cycle of TRC slabs and improve mechanical properties.


2017 ◽  
Vol 735 ◽  
pp. 18-23
Author(s):  
Yuta Kashitani ◽  
Shinichi Nishida ◽  
Junshi Ichikawa ◽  
Hiroto Ohashi ◽  
Naoshi Ozawa ◽  
...  

This paper describes a vertical type twin roll strip casting process for producing aluminum alloy strip of ADC12, A3003 and A7075. Twin roll casting process is able to produce a strip from molten metal directly. Thus this process has a possibility to reduce total cost of sheet making comparing to conventional rolling process. Aluminum alloy ADC12 is a casting material that is used for die casting. A3003 is known as a wrought aluminum alloy for aluminum can body sheet. The A3003 sheet is generally produced by rolling, so it is effective for reducing a process cost to produce the strip by twin roll casting process. Aluminum alloy A7075 has high tensile strength, and it is known as a material for aerospace application. The sheet is manufactured in small quantities comparing to the other sheet aluminum alloy. It is supposed that the demand of high tensile strength aluminum sheet such as A7075 is going to increase for weight saving of structural material. In this study, twin roll casting experiment was performed to produce these three aluminum alloy strip in same experimental conditions. Castability, surface conditions and strip thickness were estimated. It was possible to cast these aluminum alloy strip.


2010 ◽  
Vol 139-141 ◽  
pp. 477-480
Author(s):  
Ryoji Nakamura ◽  
Shuya Hanada ◽  
Shinji Kumai ◽  
Hisaki Watari

An inline hot rolling was operated on 5182 aluminum alloy strip cast using a vertical type high speed caster (VHSTRC) at the speed of 60 m/min. A porosity existing at center line of the thickness and a ripple mark on the surface, these are typical defects of the strip cast by the VHSTRC, could be improved by the inline rolling. The rolling speed was as same as the roll-casting-speed of 60m/min. The temperature of the strip, when the inline rolling was operated, was 450oC. The reduction of the strip of the inline rolling was 35%.


2021 ◽  
Vol 11 (12) ◽  
pp. 5550
Author(s):  
Yuqiang Chen ◽  
Chuang Xiong ◽  
Wenhui Liu ◽  
Suping Pan ◽  
Yufeng Song ◽  
...  

The influences of cold rolling and subsequent heat treatment on the microstructure evolution of 2524 alloy were investigated using an orientation distribution function (ODF) and electron back-scattered diffraction (EBSD). A preparation method of 2524-T3 aluminum alloy with a strong Brass texture was developed, and its effect on the fatigue properties of the alloy was investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that with the increase in cold rolling deformation from 0% to 80%, the volume fractions of Brass, copper, and S textures in the 2524-T3 alloy also increase, especially in the case of Brass and S textures. However, the volume fractions of cube and Goss textures are reduced significantly, especially for cube textures, which are decreased by 57.4%. Reducing coarse second-phase particles (CSPs) is conducive to the formation of a strong deformation texture during cold rolling. A 10% deformation at each rolling pass, followed by a step annealing, helps the preservation of a Brass texture even after solution treatment at 500 °C for 0.5 h, while a large cold deformation followed by high-temperature annealing helps the formation of a strong cube texture. The Brass texture can enhance the strength while decreasing the fatigue crack growth resistance of this alloy.


Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1713 ◽  
Author(s):  
Yong Li ◽  
Chen He ◽  
Jiadong Li ◽  
Zhaodong Wang ◽  
Di Wu ◽  
...  

The main purpose of this present study was to investigate the different processing conditions on the microstructure, segregation behavior of alloying elements, and mechanical properties of Al−Mg−Si alloy twin-roll cast slab prepared using a novel twin-roll casting technology. The simulation of temperature field, distribution of alloying elements, tensile properties, hardness, and conductivity were examined by a Leica optical microscope, scanning electron microscopy, energy dispersion spectroscopy, electron probe microanalysis, and tensile tests. The results indicated that when the traditional twin-roll casting method was used to produce aluminum alloy strip, there are obvious centerline segregation defects due to the deep crystallization front depth and symmetrical solidification characteristics. When the forced-cooling technology was applied in the twin-roll casting process, by virtue of the changing of crystallization front depth and crystallization front shape, the segregation defects are obviously suppressed. Suggesting that this method can significantly improve the uniformity of alloying elements in the thickness direction of the twin-roll cast slab, ultimately improve the mechanical properties of AA6022 aluminum alloy.


Sign in / Sign up

Export Citation Format

Share Document