Equal channel angular pressing of a TWIP steel: microstructure and mechanical response

摘要: A Fe–20.1Mn–1.23Si–1.72Al–0.5C TWIP steel with ultrafine grain structure was successfully processed through equal channel angular pressing (ECAP) at warm temperature up to four passes following the B C route. The microstructure evolution characterized by electron backscattered diffraction obtain maps, which revealed an obvious reduction in size, as well a decrease twin fraction, increasing number of ECAP passes. texture during analyzed orientation distribution function. results show that annealed material presents brass (B) dominant component. After ECAP, one pass sample A 1* and 2* strongest components, while two samples change gradually toward $$ B/\bar{B} $$ components. TEM analysis shows all present twins. thickness is reduced Nano-twins, result secondary twinning, are also observed samples. In sample, extensively refined joint action subgrains, grains mechanical behavior studied tensile samples, it found yield strength ultimate significantly enhanced Although ductility strain hardening capability process, significant uniform deformation periods positive work rates.