Abstract: Disclosed are mixtures for use in additive manufacturing, wherein the powder mixture comprises first and second materials. The first material includes a metal alloy or a mixture of elemental precursors thereof, and is in powder form. The second material includes a reinforcement material comprising powder particles having a particle diameter of from 1 to less than 30 ?m (as determined by laser scattering or laser diffraction). The inventive powder mixtures allows for the processing to three dimensions objects which are free of cracking and which thus have favourable mechanical characteristics. Further disclosed are processes for the preparation of corresponding powder mixtures and three dimensional objects, three dimensional objects prepared accordingly and devices for implementing processes for the preparation of such objects, as well as the use of a corresponding powder mixture to suppress crack formation in a three-dimensional object, which is prepared by additive manufacturing.