The Thixomolding® process has a 20-year track record of research with commercial applications beginning in 1992. The apparatus machine is similar to those used for an injection plastic molding: it transforms in a single step magnesium chips heated to a semisolid slurry (inside a barrel and screw) into precision molded parts. Originally employed by Asian manufacturers for consumer electronics and consumer hardware applications (such as notebook computer cases, digital camera bodies and chain saw housings, etc.), the industrial uses of Thixomolding® has been widely extending from last years to other parts suppliers in the Americas, Europe and Asia. Nowadays thixomolded parts there are in automotive and sport equipment as automotive shift cams, bike saddle, fishing reels, snowboard bindings, etc. Thanks to the semisolid and thixotropic state of magnesium, the slurry moves in laminar flow inside the mould. The absence (or very low) of turbulence allows to reduce drastically (and often to eliminate) residual porosity which is typical of die-casting. In this work a thixomolded AZ91D has been characterized by tensile and axial fatigue testing (fatigue ratio R=0.1) both in the as-supplied condition and after a Tx heat treatment.