| 摘要 |
PROBLEM TO BE SOLVED: To provide rolled bar steel material for which a descaling treatment can be eliminated or simplified, and a manufacturing method of a processed product of the rolled bar steel material using the rolled bar steel material.SOLUTION: Rolled bar steel material according to the invention has ferrite and a coating covering the ferrite, the coating having sugar compound. The ferrite preferably includes C: 0.1 mass% or more and 1.5 mass% or less, Cr: 0.01 mass% or more and 3 mass% or less, Si: 0.01 mass% or more and 2.5 mass% or less, and Mn: 0.01 mass% or more and 2 mass% or less. A manufacturing method of a processed product of the rolled bar steel material according to the invention includes steps of: annealing for softening the rolled bar steel material; forming a lubricant layer on a surface on the rolled bar steel material annealed for softening; and processing the rolled bar steel material with the lubricant layer formed. The process of annealing for softening has a heating temperature of 600°C or more and 900°C or less, and a heating time of 5 hours or more and 24 hours or less. |
