Tunneling magnetoresistive (TMR) elements and associated methods of fabrication are disclosed. In one embodiment, the TMR element includes a ferromagnetic pinned layer structure, a tunnel barrier layer, and a free layer having a dual-layer structure. In one embodiment, the free layer includes a first amorphous free layer and a second amorphous free layer. In another embodiment, the free layer includes a first polycrystalline free layer and a second amorphous free layer. The compositions of the first free layer and the second free layer of the dual layer structure differ to provide improved TMR performance and controlled magnetostriction. In one example, the first free layer may have a composition optimized for TMR while the second free layer may have a composition optimized for magnetostriction.