Influence of yttrium additions on the hot tearing susceptibility of magnesium–zinc alloys

An Investigation on Hot Tearing of Mg-4.5Zn-(0.5Zr) Alloys with Y Additions

“…0:98 the structure develops considerable strength and solid-state creep can compensate the strain caused by thermal contraction. [14,23] Generally, the HTS is proportional to the solidification range, especially the vulnerable solidification region. [22] Therefore, for Mg-4.5Zn-xY alloys, a simplified version of Clyne and Davies' model (DT) was proposed as follows [14] :…”

“…In contrast, the investigations on their castability, especially hot tearing, are very limited. Recently, Gunde [14] investigated the influence of Y additions on the HTS of Mg-3Zn-0.5Zr alloys. The results indicated that adding Y has a very positive effect on the hot tearing of Mg-3Zn-0.5Zr alloys.…”

High-strength magnesium alloys for degradable implant applications

“…It was also observed that the solidus temperature (T S ) of the castings increased upon the addition of Yb. This increase in T S resulted in a smaller terminal freezing range (TFR) than that of the Yb-free alloy and, because the TFR correlates with the hot tearing susceptibility [23], also caused a reduction in the (generally high) hot tearing susceptibility of Mg-Zn alloys. Fig.…”

“…However, the following effects can be attributed to ytterbium: (i) Yb reduces the alloy's grain size due to its contribution to the grain growth restriction factor [8]; (ii) Yb reduces the hot tearing susceptibility during casting by increasing the solidus temperature and consequently decreasing the terminal freezing range [23]; and (iii) Yb is present in the large 0.5-2 m IMP particles on the grain boundaries and thus affects the grain-boundary pinning. It is noteworthy that Yb additions do not considerably increase the cost of the alloy (price of Yb: circa 120 D kg −1 ).…”

Hot Tearing of 9Cr3Co3W Heat-Resistant Steel during Solidification

“…It is of great importance to obtain the critical temperature and stress conditions of hot tearing generating for optimizing the production process and improving the quality of castings. A number of hot tearing susceptibility experiments [15][16][17] have been done by impeding the shrinkage of molten alloy to generate hot cracks during solidification, and then authors have quantified the number of cracks and assessed the severity of cracks. Unfortunately, hot tearing experiments [15][16][17][18][19][20] consist mostly of low melting point alloys, which could not provide guidance for the casting process of steel castings.…”