Effect of thermomechanical treatment on the microstructure and mechanical properties of Al-40Zn-3Cu alloy

UZUN M., KARABIYIK S., ALEMDAĞ Y., Savaşkan T.

Journal of Alloys and Compounds, cilt.1022, 2025 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 1022
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.jallcom.2025.179894
  • Dergi Adı: Journal of Alloys and Compounds
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Public Affairs Index, Civil Engineering Abstracts
  • Anahtar Kelimeler: Aging, Al-Zn alloys, Mechanical properties, Microstructure, Multi-directional forging, Severe plastic deformation
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

Effect of thermomechanical treatment including homogenization, multi directional forging, and quench-aging on the microstructure and mechanical properties of Al-40Zn-3Cu alloy were studied by metallography and mechanical tests. The metallographic examinations were performed by scanning electron microscope, X-ray diffractometer, scanning-transmission electron microscope and electron backscatter diffractometer. The mechanical properties were determined through hardness, tensile and impact tests. Aging after multi directional forging, solution treatment, and quenching resulted in grain refinement and alteration in the morphology of Zn-rich precipitates in the microstructure of the alloy. These changes improved the strength of the alloy but decreased its ductility. However, its ductility increased with increasing aging temperature. The average grain size of the alloy in the homogenized condition was measured to be 55 ± 15 µm. After multidirectional forging and aging at 100 °C, 150 °C and 200 °C, the average grain size decreased to 24 ± 6 µm, 11 ± 5 µm and 9 ± 4 µm, respectively. The alloy after multi-directional forging and aging at 100 °C showed the highest hardness (186 ± 3 HB), yield strength (436 ± 4 MPa) and ultimate tensile strength (516 ± 2 MPa) but the lowest elongation (2 ± 1 %) and impact energy (140 ± 8 kJm−2). As the aging temperature increased, the elongation and impact energy of the alloy increased, but its hardness and tensile strength decreased. The alloy exhibited highest quality index (582 MPa) after multidirectional forging and aging treatment at 150 °C. The mechanical tests results were evaluated in relation to the microstructural alterations caused by the applied treatments.