Fatigue behaviour of HIPed and stress relieved Ti6Al4V alloy specimen’s produced by SLM was analysed (Rε = -1). The HIP process caused a microstructural transformation decreasing the hardness and monotonic properties that not allowed fatigue strength increase. A bilinear behaviour in the elastic strain-fatigue life curve was observed, because of Young´s modulus decrease during the cyclic elasto-plastic tests consequence of subgrains formation. The Smith-Watson-Topper and total strain energy density models showed a good concordance between predicted and experimental fatigue lives in notched samples.

Fatigue behaviour of HIPed and stress relieved Ti6Al4V alloy specimens produced by SLM was analysed (Rε = -1). The HIP process caused a microstructural transformation decreasing the hardness and monotonic properties that not allowed fatigue strength increase. A bilinear behaviour in the elastic strain-fatigue life curve was observed, because of Young´s modulus decrease during the cyclic elasto-plastic tests consequence of subgrains formation. The Smith-Watson-Topper and total strain energy density models showed a good concordance between predicted and experimental fatigue lives in notched samples.