The Microstructure Evolution and Control of Alloy 690 during Cold Rolling

2013 ◽  
Vol 573 ◽  
pp. 95-103
Author(s):  
Zhi Hao Yao ◽  
Jian Xin Dong ◽  
Zhi Yong He ◽  
Mai Cang Zhang

The microstructure evolution and control for Alloy 690 during cold rolling and annealing treatment was investigated. Cold rolling specimens were deformed in the strain range from 15% to 70% with strain rates from 0.01 to 10s-1. Subsequent annealing treatment was carried out in the range of 1060~1100°C for dwell time 3~15mins. Rolling reduction, annealing temperature and annealing time except strain rate had obviously influence on grain size and hardness. Little coarsening of grains were observed below 1060°C during annealing treatment, whereas grains coarsened obviously over 1080°C. Besides, the behavior of grain growth for alloy 690 was investigated systematically.

2007 ◽  
Vol 546-549 ◽  
pp. 1997-2002 ◽  
Author(s):  
Shao Kai Chen ◽  
C.F. Liu ◽  
Ping Xiang Zhang ◽  
Lian Zhou

Influence of cold rolling total thickness reduction, annealing temperature and annealing time on the textures in powder metallurgic Ni-5at.%W substrate tapes have been quantitatively investigated with the EBSD (Electron Back-Scattered Diffraction) technique. A “copper” type-like texture consisting of {1 2 3}<6 3 –4>+{0 1 –1}<3 –1 –1>+{1 –1 2}<1 –1 –1> has been found in the as-rolled tapes. This texture was much intensive in the tape at 99% thickness reduction than in the tape at 87% thickness reduction. The 99% reduction tape showed a higher fraction and sharper cube texture than the 87% reduction tape after annealing treatment. In addition, annealing at 1000°C was much favourable for the cube texture formation than annealing at 950°C and resulted in a higher cube texture fraction.


2018 ◽  
Vol 939 ◽  
pp. 73-80 ◽  
Author(s):  
Ansel Fabianta Tambunan ◽  
Irene Angela ◽  
Imam Basori ◽  
Bondan Tiara Sofyan

The microstructures, mechanical properties, deformation mechanism, and recrystallization behavior of Cu-Zn-Bi alloys for cartridge case application have been investigated in this research. Cu-28Zn-1.1Bi wt. % alloys were produced by gravity casting and subjected to a homogenization – cold rolling – annealing sequences with variations on reduction level and annealing temperature. Samples characterizations were done through optical emission spectroscopy, optical microscopy, SEM-EDS imaging, and X-ray mapping modes, while hardness measurements were performed using micro Vickers method. The presence of Bi was found to increase cartridge brass hardness through a dispersoid strengthening mechanism in which dislocation movements are rendered by Bi particles. Higher deformation levels resulted in higher microhardness of the alloy. Recrystallization took place at grain boundaries and areas surrounding Bi dispersoid at 400 °C, while further heating resulted in grain growth phenomenon. Bismuth addition accelerated the recrystallization process in cartridge brass by a particles stimulated nucleation (PSN) mechanism.


2020 ◽  
Vol 833 ◽  
pp. 3-7
Author(s):  
Aryya Satwiko Mahardika ◽  
Ignatius Andre Setiawan ◽  
Bondan Tiara Sofyan

Bullet cases are usually made of Cu-28Zn alloy through various kinds of process such as cold rolling, deep drawing, and annealing. Alloying is needed to improve properties that increase forming capabilities of cartridge brass, one option is by addition of Al. Samples used in this research were prepared by melting Cu, Zn, and Al ingots in an induction furnace, followed by gravity casting. As cast samples were homogenized at 800 °C for 2 h followed by cold rolling for 5, 10 and 20 %. Annealing was conducted on the 20 % deformed samples at 300, 400, and 600 °C for 30 min. Hardness and microstructures formed by each treatment were then evaluated using Vickers microhardness test as well as optical and scanning electron microscopy. Addition of Al deteriorated Cu-28Zn alloy forming capabilities by reducing its ductility. It is also found that addition of Al reduced recrystallization temperature. Partial nucleation was found to occur locally around the edge of samples at 300 °C and 400 °C. Annealing at 400 °C exhibited γ phase precipitation due to the decomposition of β phase. While, homogeneous full recrystallization was achieved at 600 °C.


2013 ◽  
Vol 551 ◽  
pp. 210-216 ◽  
Author(s):  
Alireza Ghaderi ◽  
Peter D. Hodgson ◽  
Matthew R. Barnett

This study focuses on the microstructure and texture evolution of a Ti-5Al-5Mo-5V-3Cr alloy during cold rolling and annealing treatments. Three samples with different initial microstructures were cold rolled to a 40% reduction in thickness. The starting microstructure of one sample was single β phase while two other specimens were α+β phases with different α particle sizes, distributed in β grains. For all three samples, the average size of primary β grains was 150 µm. The cold rolled specimens were then annealed at 860 °C (10 °C above the β transus temperature) for 5 minutes followed by water quenching. Microstructure development during cold rolling and recrystallization was studied by scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) technique. Microstructure investigations showed that massive amount of shear bands occurred during the cold rolling of the single β phase sample while only a few shear bands were observed in the α+β cold rolled microstructures. The cold rolled texture of the sample comprised of a single β phase contains a gamma fibre (//ND) and a partial alpha fibre (//RD). Annealing treatment decreased the intensity of the cold rolled texture in the single β phase sample. Also, it was found that the presence of α precipitates changes the common annealing texture observed in the single β phase specimen.


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