Investigation of the Influence of Deoxidation and Chemical Composition on Notched-Bar Properties of Ship Plate Steels

This report summarizes the results of the investigation which included studies on approximately 400 steels. In order to condense the information, references are made to progress reports containing original data supporting conclusions drawn in this report. Some technical articles based on these reports have been published. The majority of the data was obtained on steels made in 200-lb. melts and processed in the laboratory. All of the laboratory heats were made in an induction furnace using standardized melting practices. Unless otherwise noted, they were rolled to 3/4-in. plate using a finishing temperature of 1850 F. Two base compositions for semikilled steels were investigated. One was similar to ABS Grade B steel in composition (Type B heats). The other was similar to ABS Grade A steel (Type A heats) and resembled the ship steel used during World War II. The effects of carbon, maganese, phosphorus, nitrogen, and sulfur were investigated on semikilled steels. Silicon and aluminum were the principal deoxidizers studied. The investigation of composition was supplemented by limited studies of the effects of hot working and cooling variables on notched-bar properties and fracture characteristics of ship plate steel.