Effect of the cyclic expansion-extrusion (CEE) process on mechanical properties and the grain refinement of AA6061 aluminum alloy



  • Do Xuan Truong Factory Z119, Air Defence - Air Force
  • Nguyen Manh Tien (Corresponding Author) Le Quy Don Technical University
  • Nguyen Manh Hung Le Quy Don Technical University
  • Nguyen Truong An Le Quy Don Technical University




CEE; Aluminum alloy AA6061; Microhardness; Microstructure; UFGs


In this work, the cyclic expansion-extrusion (CEE) process for aluminum alloy AA6061 is due to its wide industrial applications. First, The CEE process is performed to create a fine stable grain size for the studied alloy. The microhardness of the deformed samples was determined to evaluate the effect of the CEE process on the mechanical properties of the alloy. The average microhardness of the deformed samples increased sharply after 1 CEE cycle from 40 Hv to 65 Hv or 68 Hv. It is particularly noticeable that in subsequent cycles, the average microhardness of the samples hardly changes (Hv ≈ 70). Subsequently, the microstructural survey was conducted to determine the average grain size of deformed samples. The average grain size reached about 5 ÷ 6 µm from the initial value of 100 μm after four CEE cycles. The results show that the effect of the cumulative strain of the CEEed samples significantly on the mechanical properties as well as for the grain refinement to create ultrafine grains (UFGs) in microstructures of the AA6061 alloy.


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How to Cite

Do Xuan Truong, M. T. Nguyen, Nguyen Manh Hung, and Nguyen Truong An. “Effect of the Cyclic Expansion-Extrusion (CEE) Process on Mechanical Properties and the Grain Refinement of AA6061 Aluminum Alloy”. Journal of Military Science and Technology, vol. 87, no. 87, May 2023, pp. 100-7, doi:10.54939/1859-1043.j.mst.87.2023.100-107.



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