Metallurgical Engineering

Metallurgical Engineering

Investigating of the cold rolling and annealing effects on microstructure and mechanical properties of nanostructured Ni-Cr-Mn Marajing steel

Document Type : Research Paper

Authors
Abstract
cold rolling and annealing of structures with a high percent of Martensite are the new subgroups of advanced thermomechanical processes that are known as Martensite process. In this study, an alloying steel with the Nominal composition of Fe-5Ni-10Cr-8Mn (weight percent), was casted InaVacuum Arc Remeltingfurnace and after homogenizing, was placed under two steps cold rolling (until 50 %) and two steps of annealing after rolling (in different temperatures). XRD, hardness and tensile tests and EBSDinvestigation was done on samples. Results show that two step rolling and annealing at 600  for 1 hour is the most optimize state for receiving to ultra fine grained structure / nanostructure. Also, residual austenite that caused during two phase annealing in this alloy, is mechanically unstable and this phase is transferred to Martensite phase during loading and is shown TRIP property. Tensile strength of this steel is 1050 MPa under optimal state and the percent of elongation of this steel is about 28 %. This elongation creates before necking. 
Keywords

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