PURPOSE: To prevent the infiltration of diffusing hydrogen into a PC rod wire and to improve its delayed fracture resistance, at the time of producing the PC rod wire, by finely dispersing MnS into the structure.
CONSTITUTION: At the time of producing a construction PC rod wire, as the stock, steel contg., by weight, 0.10 to 0.39% C, 0.10 to 2.0% Si, 0.20 to 2.0% Mn, 0.005 to 0.10% Zr, ≤0.015% P, 0.003 to 0.015 S and ≤0.010% N or furthermore contg., as material strengthening elements, one or ≥two kinds among 0.01 to 1.0% V, 0.01 to 0.5% Ti, 0.01 to 0.5% Nb and 0.0002 to 0.005% B is used. Since the oxides of Zr finely disperse into the steel to work as the effective precipitation site of MnS, MnS infiltrating into the PC rod wire to form the trapping site of diffusing hydrogen causing delayed fracture is finely dispersed to improve its delayed fracture caused by hydrogen, by which the PC rod wire having ≥1500Mpa class tensile strength and excellent in delayed fracture resistance can be produced.
| JP3786190 | METHOD OF PRODUCING RARE EARTH SINTERED MAGNET |
| JPS61269302 | MAGNETIC THIN FILM |
KODAMA JUNICHI
TASHIRO HITOSHI
