| Abstract Scope |
This study is a follow up on investing the influence of adding Nd and La to extruded Mg10Gd on mechanical properties. Previous research showed that an increase in tensile strength by decreasing grain size and increasing volume fraction of RE-rich precipitates with increasing the amount of alloying elements. The alloys containing La appeared less ductile in 3-point-bending tests. Precipitation hardening caused strong grain growth, most significant in Mg10Gd – resulting in half the outer-strain value to crack initiation. Alloys containing Nd showed a precipitation hardening response, but the increase in strength was on the expense of ductility, here fractography reveals the highest amount of large cleavage planes. Crack propagation in Mg10Gd alloy is mostly driven by twinning. Increased amount and size of second phases by addition of Nd and La suppress twinning, but the crack initiation and propagation is caused by brittle, coarse second phases, mostly in alloys containing La. |