PURPOSE: To manufacture a galvanized steel sheet formed product having high strength and excellent corrosion resistance by irradiating with high density energy followed by melting and solidifying the required part of the formed product made of a specific composition of low carbon steel subjected to galvanization and having excellent workability.
CONSTITUTION: Zn based metal is plated by 10-200g/m2 quantity on the steel sheet with ferritic structure and having the composition contg. 0.002-0.02wt.% C, <0.5% Si, 1.0-3.0% Mn, <0.1% Al, <0.2% P, <50ppm B or further, <0.1% Ti or Nb and further containing at least one kind between <0.02% Ca and <0.1% Mg and having K1 value of 0.01 shown by (Mn%+250×B%)×C%, or on the steel sheet having the composition contg., besides the above, C, Si, Mn, Al, P and B contents, further at least one kind among the specific quantities of Cu, Ni, Cr, Mo, Zr, V and W and having K2 value of 0.01 shown by (Mn%+ Cr%+Mo%+250×B%)×C%. Successively, this galvanized steel sheet is irradiated with the high density energy of laser beam, etc., and melted and solidified.
KASE TOMOHIRO
MAKII KOICHI
SATO AKIHITO
TOMIOKA YOSHIRO
NAKAMURA SHINICHIRO
TOYOTA MOTOR CORP
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