Hot-dip galvanized steel sheet

A hot-dip galvanized steel sheet, comprising:

• a chemical composition represented by:
• in terms of mass %,
• C:
• 0.14 to 0.3%;
• Si:
• 0.001 to 2.0%;
• Mn:
• 2.0 to 4.0%;
• P:
• 0.05% or less;
• S:
• 0.01% or less;
• N:
• 0.01% or less;
• Al:
• 0.001 to 1.0%;
• Ti:
• 0.001 to 0.10%;
• B:
• 0.0001 to 0.01%;
• Mo:
• 0 to 0.50%;
• Cr:
• 0 to 0.80%;
• Ni:
• 0 to 1.00%;
• Cu:
• 0 to 1.00%;
• V:
• 0 to 0.50%;
• Nb:
• 0.0 to 0.10%;
• Ca:
• 0.00 to 0.01%;
• Mg:
• 0.00 to 0.01%;
• REM:
• 0.00 to 0.01%;
• Bi:
• 0.00 to 0.01%;
• and
• the balance:
• Fe and impurities;
• and
• a steel structure represented by:
• in terms of area ratio,
• polygonal ferrite:
• 10% or less;
• upper bainite:
• 20% or less;
• retained austenite:
• 5% or less;
• and
• martensite:
• 70% or more, wherein:
• martensite having Fe carbides at a number density of 1×106/mm2 or more is contained by 50% or more, in terms of area ratio, with respect to the entire amount of martensite;
• and
• the steel structure has an average effective crystal grain diameter of 5.0 μm or less.