Support structures are used in certain additive fabrication processes to permit fabrication of a greater range of object geometries. For additive fabrication processes with materials that are subsequently sintered into a final part, an interface layer may be fabricated between the object and support in order to inhibit bonding between adjacent surfaces of the support structure and the object during sintering. Interface layers suitable for manufacture with an additive manufacturing system may resist the formation of bonds between a support structure and an object during subsequent sintering processes.