Effect of praseodymium and erbium additions on solidification characteristics, microstructure and mechanical properties of as–cast ZRE1 magnesium alloy

Abstract

In this research, computer‐aided cooling curve thermal analysis, microstructure analysis, hardness measurements, and tensile test were performed to investigate the effect of praseodymium (Pr) and erbium (Er) additions on as‐cast ZRE1 magnesium (Mg) alloys. Results from the cooling curve and microstructure analysis showed that praseodymium and erbium altered the grain size of the alloys. Thermal analysis result demonstrated an increased solidification rate with praseodymium and erbium additions. Furthermore, the grain size was reduced by approximately 16 % and 15 % with the addition of praseodymium and erbium, respectively. Scanning electron microscopy/energy dispersive X‐ray spectroscopy results showed that praseodymium combined with the original second phase and formed Mg−Zn‐Pr−Ce, and erbium dissolved into the α‐Mg matrix. Both additives improved the hardness and ultimate tensile strength of the ZRE1 magnesium alloy.

Solidification, Microstructure and Mechanical Properties of Mg-2.8Nd-1.5Gd-0.5Zn-0.5Zr Cast Alloy with Erbium Addition

“…The results showed that the Mg-Zn-RE phase of base alloy was formed at 526.8 °C and With addition of 0.25 wt.% Er, the T Eu Mg-Zn-RE temperature of Mg-Zn-RE phase decreased by 0.8 °C. The smaller magnitude of this effect compared with that of the previous addition may be due to the Er content in the intermetallic secondary phase [9].…”

“…The experimental results showed that when 0.25 wt.% Er is added, the nucleation temperature of α-Mg phase decreases, which obtained at 643.8 °C. It is reported that the addition of erbium into Mg-Zn alloys facilitated the formation of the α-Mg phase at around 638°C, and this phase appeared as the first peak, which corresponded to the solidification of the magnesium matrix [9,14].…”

“…% of Er, which obtained at 627.7 °C. The decrease in the nucleation growth of α-Mg phase led to the decrease in the solidus temperature and simultaneously widened the solidification range [9].…”

“…Generally, magnesium strengthening through rare earth addition results from grain boundary strengthening caused by precipitates and solid solution. Mg-RE alloys are used in military aircrafts and aerospace applications [9]. Adding Erbium into a Mg-Zn-Zr alloy improves the deformability of the latter and leads to the formation of a fine and uniform microstructure.…”

Solidification and microstructure characterizations of eutectic aluminum‐silicon casting alloy with the addition of tin

“…This method is usually used during cooling or heating, especially solidification or melting. The most common techniques are Differential scanning calorimetry, Differential thermal analysis, thermogravimetric analysis, and cooling curve thermal analysis [9–11]. To increase measurement accuracy, the size of samples must be big enough and solidify over long enough time.…”