Turbine casing made of two materials

The invention proposes a casing (30) of an aircraft turbine (16), intended to support a set of ring sectors (28) which partly delimits a channel for the passage of a gas stream through the turbine (16), where the casing (30) includes means for dynamic adjustment of the radial position of the ring sectors (28) by controlled injection of an air stream on to portions (36) of an annular wall (34) of the casing (30), where the casing (30) includes an upstream radial tab (38) which connects an upstream end of each ring sector (28), in the flow direction of the gas stream, to the casing (30), and a downstream radial tab (40) which connects a downstream end of each ring sector (28) to the casing (30), where both upstream and downstream radial tabs (38, 40) are made from a single piece with the casing (30), characterised in that each radial tab (38, 40) is made as two portions (42, 44) from different materials.