Spheroidal graphite cast iron is an engineering material which has proved its importance during previous decades. However, limited workability of this material could be a challenge for spreading of its applications and there is a little knowledge about severe straining of this material at warm and/or cold regimes. This work is conducted to examine imposition of a well-known severe plastic deformation process called equal channel angular pressing on this material through a warm deformation regime. For this purpose, a casing procedure combined with an pre-annealing treatment is applied to increase the workability of this material. Results show that an equivalent plastic strain as great as 0.9 can be successfully imposed on the spheroidal graphite cast iron at a temperature lower than half of the melting temperature of iron while no evidence from dynamic recrystallization of the ferrite phase is traced. This enhanced warm workability of SG cast iron is related to imposition of a compressive stress state as well as decrease of pearlite fraction by the pre-annealing.

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