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

Abstract:

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.

• Periodical: Key Engineering Materials (Volume 833)
• Pages: 3-7
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.833.3
• Online since: March 2020
• Authors: Aryya Satwiko Mahardika, Ignatius Andre Setiawan, Bondan Tiara Sofyan*
• Keywords: Aluminium, Annealing, Cartridge Brass, Cold Rolling, Dislocation Induced Precipitation, Recrystallization

References

[1] Basori, I., and Sofyan, B.T. Initial Observation on the Characteristics of Small Caliber Cartridge Case Before and After Firing,. Prosiding Seminar Nasional Mesin dan Teknologi Kejuruan. Universitas Negeri Jakarta, 27 Mei 2015, pp.351-356.

[2] Hajizadeh, K., Tajally, M., Emadoddin, E., Borhani E. Study of Texture, Anisotropy and Formability of Cartridge Brass Sheets., J Alloys Comp 588 (2014): 690-696.

DOI: 10.1016/j.jallcom.2013.11.091

[3] Sofyan, B. T., and Basori, I. Effects of Deformation and Annealing Temperature on the Microstructure and Mechanical Properties of Cu-32Zn Brass,. ARPN JEAS 11 (4) (2016): 2741-2745.

[4] Basori, I., Angela, I., Jendra, D., Sofyan, B.T. Deformation Characteristics and Texture Development of Bi-added Cu-29Zn Alloys,. IOP Conf Ser Mater Sci Eng 378 (2018) 012015.

DOI: 10.1088/1757-899x/378/1/012015

[5] Basori, I., Pratiwi, H.I., Sofyan B.T. Effect of Manganese on the Microstructures, Mechanical Properties and Deformation Characteristics of Cu-29Zn Alloy,. Mater. Sci. Forum. 917 (2018): 212-217.

DOI: 10.4028/www.scientific.net/msf.917.212

[6] Ovat, F. A., Asuquo, L.O., Abam, F.I. The Influence of Aluminium and Manganese on some Mechanical Properties of Brass., RJEAS 4 (2012): 214-218.

[7] Liu, R., Shang, W., Huang, Z., Wang, Y. Effects of Annealing Temperature and Al content on Microstructures and Properties of Al-brass., Procedia Eng. 27 (2012): 1823-1828.

DOI: 10.1016/j.proeng.2011.12.656

[8] Zhang, Y., Tao, N. R., Lu, K. Effects of Stacking Fault Energy, Strain Rate, and Temperature on Microstructure and Strength of Nanostructured Cu-Al Alloys subjected to Plastic Deformation,. Acta Mater. 59 (15) (2011): 6048-6058.

DOI: 10.1016/j.actamat.2011.06.013

[9] Humphreys, F. J., Hatherly, M. Recrystallization and Related Annealing Phenomena. Oxford: Elsevier. (2004).

[10] Meyers, M. A., Vohringer, O., Lubarda, V. A. The Onset of Twinning in Metals: A Constitutive Description,. Acta Mater. 49 (19) (2011): 4025-4039.

DOI: 10.1016/s1359-6454(01)00300-7

[11] Bader M., Elddis G.T., Warlimont H. The Mechanism of Anneal Hardening in Cu-Al Alloys,. Metal Transaction A 7 (2) (1976): 249-255.

DOI: 10.1007/bf02644464