Effect of Strain on Microstructures and Mechanical Properties of Warmly Deformed SCRAM Steel for Fusion Application

Abstract:

The SCRAM steel was processed by warm deformation on Gleeble-3500 thermo-simulation machine. The effect of strain on the microstructures and mechanical properties of SCRAM steel was investigated. The results show that an increase in the strain can result in refining the martensitic laths, increasing the volume fraction of precipitates and the dislocation density in SCRAM steel. The martensitic lath width decreases from 0.83 μm to 0.48 μm and the dislocation density increases from 1.3 × 10¹⁵ m^-2 to 6.4 × 10¹⁵ m^-2 in SCRAM steel. The specimen exhibits high ultimate tensile strength and yield strength but low reduction of area and total elongations when the strain (ε) is up to 0.5. The tensile fracture surface observation indicates that dimples become smaller and shallower while tear ridges drastically grow up with the strain increasing.

• Periodical: Advanced Materials Research (Volumes 941-944)
• Pages: 1463-1468
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.941-944.1463
• Online since: June 2014
• Authors: Yang Mou, Li Hong Xue*, Qi Lai Zhou, Cai Xuan Lu, You Wei Yan
• Keywords: Mechanical Property, Microstructure, Strain, Warm Deformation

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