Tooling for use during heat treatment to support a preform made of powder

A tool for supporting a metallic or ceramic preform 2100 during heat treatment, the preform comprising a bearing surface and suspended surface, comprising: a tray 220; and a plurality of support blocks 2300, movable relative to one another by sliding on the tray. Preferably, a drive element 2400, comprising a metal or ceramic powder with an organic binder, connects the blocks and shrinks under the effect of temperature. Preferably, a plurality of rods extend through channels in the blocks and comprise abutments at the end. Preferably, blocks are hollow, comprise a fillet and are made from ceramics or metallic alloys. Preferably, blocks yttrium oxide anti-diffusion layers on top surface and tray has a polished alumina or yttrium oxide top layer. Preferably, blocks and drive mechanism are formed from same powder as preform and are sintered before adding preform. Preferably, preform part is for aviation.