Investigation of the effect of various Ca content on microstructure and mechanical properties of as-cast ZK60 Magnesium alloys


Akbas A., ZEREN M.

JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI, sa.3, ss.1061-1069, 2023 (ESCI) identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2023
  • Doi Numarası: 10.2339/politeknik.1052154
  • Dergi Adı: JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI
  • Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI), TR DİZİN (ULAKBİM)
  • Sayfa Sayıları: ss.1061-1069
  • Anahtar Kelimeler: ZK60 alloy, Ca addition, microstructure, hot tensile testing, mechanical properties, GRAIN-SIZE, TEXTURE, ZN, CALCIUM, BEHAVIOR, TEMPERATURE
  • Kocaeli Üniversitesi Adresli: Evet

Özet

The effect of various Ca content on microstructure and mechanical properties of as-cast Mg-6Zn-0. 5Zr (wt. %) Mg alloys with hot tensile testing at 345 degrees C were investigated. The alloy was produced with the LPDC method [1]. Microstructural characterization as-cast alloy demonstrated that wt.% Ca content increase, grain size decreases till wt.% 0.8Ca, the further increase affects gradual change in grain size to similar to 60 mu m at 345 degrees C. Therefore, increase in Ca ratio from 0.4 wt% forming to strip-like Mg-Zn intermetallics at grain boundaries, Ca-Mg-Zn ternary phase at grain boundary corners. Dramatical decrease in yield and tensile strength at wt% 1.6Ca addition is 37.6 MPa and 39.7 MPa respectively which is relatively km at 345 degrees C due to the absence of retarded DRX'ed small particles prohibited the grain growth after the TMT process. Conversely, elongation-to-fracture increases were observed as 1.26 at 345 degrees C showing the temperature-dependent texture softening results in improvement of mechanical properties. Wear rate is also affected from wt.% Ca addition so the gradual increase up to 1.2 wt% Ca is 3.70 x 10(-3) mm(3)/m. Similarly, a gradual increase in hardness values was obtained with Ca addition in ZK60 alloy. In this study, the effect of temperature-dependent Ca addition (wt %) on gradual enhancement in mechanical properties was observed at as-cast magnesium alloys.