Effect of Microstructure Degradation on Fracture Toughness of 20MnMoNi55 Steel in DBT Region. - Sumit Bhowmik; Prasanta Sahoo; Sanjib Kumar Acharyya; Sankar Dhar; Jayanta Chattopadhyay (Int. J. Manuf. Mater. Mech. Eng., 2016)