High-strength low-specific-gravity steel sheet having superior spot weldability
View Patent ↗A steel sheet including, by mass %, C: more than 0.100% and 0.500% or less, Si: 0.0001% or more and less than 0.20%, Mn: more than 0.20% and 0.50% or less, Al: 3.0% or more and 10.0% or less, N: 0.0030% or more and 0.0100% or less, Ti: more than 0.100% and 1.000% or less, P: 0.00001% or more and 0.0200% or less, S: 0.00001% or more and 0.0100% or less, and a remainder including Fe and impurities, in which a sum of a C content and a Ti content satisfies 0.200<C+Ti≤1.500 by mass %, a product of an Al content and an Si content satisfies Al×Si≤0.8 by mass %, and a specific gravity is 5.5 to less than 7.5.
1. A steel sheet comprising, by mass %,
C: more than 0.100% and 0.500% or less,
Si: 0.0001% or more and less than 0.20%,
Mn: more than 0.20% and 0.50% or less,
Al: 3.0% or more and 10.0% or less,
N: 0.0030% or more and 0.0100% or less,
Ti: more than 0.100% and 1.000% or less,
P: 0.00001% or more and 0.0200% or less,
S: 0.00001% or more and 0.0100% or less, and
a remainder including Fe and impurities,
wherein a sum of a C content and a Ti content satisfies 0.200<C+Ti≤1.500 by mass %,
a product of an Al content and an Si content satisfies Al×Si≤0.8 by mass %,
a Mn content and a P content satisfy Mn+100×P≤1.0, and
a specific gravity is 5.5 to less than 7.5.
2. The steel sheet according to claim 1 , further comprising, one element or two or more elements selected from the group consisting of, by mass %,
Nb: 0.300% or less,
V: 0.50% or less,
Cr: 3.00% or less,
Mo: 3.00% or less,
Ni: 5.00% or less,
Cu: 3.00% or less,
B: 0.0100% or less,
Ca: 0.0100% or less,
Mg: 0.0100% or less,
Zr: 0.0500% or less, and
REM: 0.0500% or less.