Industrial Innovations

Industrial Innovations

Achieving Desired Microstructure and Mechanical Properties of 40-60 Brass Alloy Processed by Severe Plastic Deformation

Document Type : Original Article

Authors
Ali Sonboli 1
Alireza Rahimi 2
1 Assistant Professor, Materials Engineering and Metallurgy, Arak University, Arak, Iran
2 BSc., Materials Engineering and Metallurgy, Arak University, Arak, Iran
https://doi.org/10.61186/jii.1.3.271
Abstract
Copper alloys (brasses) are widely used as engineering materials in shipbuilding, aerospace, petrochemical, and military industries. In this study, brass alloy 60-40, as one of the most important copper-based alloys, was subjected to severe plastic deformation (SPD) in the ECAP (Equal Channel Angular Pressing) process to improve its strength and maintain elongation percentage, which is an indicator of ductility. The process was carried out at 350 °C in C-path and up to six passes for the samples. Microstructural studies performed using optical microscopy showed that discontinuous recrystallization starts from the first pass in the alpha phase. With increasing strain, the fraction of recrystallized grains increased and the size of the new grains was smaller than the initial grains. The grain size reached less than one micron after the fifth and sixth passes. Also, examination of the microstructure of the beta phase showed that recrystallization in this phase started after the third pass and gradually spread in the structure with increasing number of passes. The results of micro hardness and uniaxial tensile tests confirmed the significant increase in the hardness and tensile strength of the alloy with increasing number of passes. Also, the elongation percentage at room temperature of the ECAP-processed samples was over 40%, which is only 15% less than the initial annealed sample. The results of this study showed that ECAP can be used to improve the mechanical properties of Cu-60Zn alloy. The refinement of grains in this process can lead to an increase in tensile strength and hardness, while the elongation can be maintained at an acceptable level.
Keywords
Severe plastic deformation
Brass alloy
Microstructure
Mechanical properties
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Industrial Innovations
Volume 1, Issue 3 - Serial Number 3
Summer 2023
Pages 271-284

  • Receive Date 14 November 2023
  • Revise Date 09 December 2023
  • Accept Date 16 December 2023