Effect of Cold Rolling and Annealing Temperature on Structure, Hardness and Electrical Conductivity of Rapidly Solidified Alloy of Al–Cu–Mn–Zr System

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.

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The Microstructure Evolution and Control of Alloy 690 during Cold Rolling

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.573.95 ◽

2013 ◽

Vol 573 ◽

pp. 95-103

Author(s):

Zhi Hao Yao ◽

Jian Xin Dong ◽

Zhi Yong He ◽

Mai Cang Zhang

Keyword(s):

Cold Rolling ◽

Microstructure Evolution ◽

Dwell Time ◽

Annealing Temperature ◽

Annealing Treatment ◽

Strain Range ◽

Strain Rates ◽

Alloy 690 ◽

Cold Rolling And Annealing ◽

And Control

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.

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Effect of Cold Rolling and Annealing Temperature on the Characteristics of Cu-28Zn-5.5Al Alloy Produced by Gravity Casting for Bullet Case Application

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.833.3 ◽

2020 ◽

Vol 833 ◽

pp. 3-7

Author(s):

Aryya Satwiko Mahardika ◽

Ignatius Andre Setiawan ◽

Bondan Tiara Sofyan

Keyword(s):

Cold Rolling ◽

Annealing Temperature ◽

Vickers Microhardness ◽

Induction Furnace ◽

Recrystallization Temperature ◽

Phase Precipitation ◽

Gravity Casting ◽

Β Phase ◽

Cold Rolling And Annealing ◽

Case Application

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.

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Effect of Cold Rolling and Annealing Temperature on the Characteristics of Cu-28Zn-3.2Mn Alloy

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/517/1/012002 ◽

2019 ◽

Vol 517 ◽

pp. 012002

Author(s):

William Horizon ◽

Syarah Khayrun Nisa ◽

Bondan Tiara Sofyan

Keyword(s):

Cold Rolling ◽

Annealing Temperature ◽

Cold Rolling And Annealing

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The Effects of Annealing at Different Temperatures on Microstructure and Mechanical Properties of Cold-Rolled Al0.3CoCrFeNi High-Entropy Alloy

Metals ◽

10.3390/met11060940 ◽

2021 ◽

Vol 11 (6) ◽

pp. 940

Author(s):

Zichao Zhu ◽

Tongtong Yang ◽

Ruolan Shi ◽

Xuantong Quan ◽

Jinlong Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Cold Rolling ◽

Annealing Temperature ◽

Crystal Defects ◽

High Entropy Alloy ◽

Rolled Sample ◽

High Entropy ◽

Cold Rolling And Annealing ◽

Cold Rolled ◽

Strength And Toughness

In this work, cold-rolling was utilized to induce a high density of crystal defects in Al0.3CoCrFeNi high-entropy alloys. The effects of annealing temperature on static recrystallization, precipitation behavior and mechanical properties were investigated. With increasing annealing temperature from 590 °C to 800 °C, the area fraction of recrystallized region increases from 26.9% to 93.9%. Cold-rolling deformation largely promotes the precipitation of B2 phases during annealing, and the characteristics of the precipitates are linked to recrystallization level. The coarse and equiaxed B2 phases exist in the recrystallized region and the fine and elongated B2 phases occupy the non-recrystallized region. Combined use of cold-rolling and annealing can remarkably enhance the strength and toughness. A partially recrystallized microstructure in a cold-rolled sample annealed at 700 °C exhibits a better combination of strength and toughness than a fully recrystallized microstructure in a cold-rolled sample annealed at 800 °C. Finally, related mechanisms are discussed.

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