Abrasion-resistant steel plate and method of producing abrasion-resistant steel plate

An abrasion-resistant steel plate comprising:

• a chemical composition containing, in mass %,
• C:
• more than 0.23% and 0.34% or less,
• Si:
• 0.01% to 1.0%,
• Mn:
• 0.30% to 2.50%,
• P:
• 0.020% or less,
• S:
• 0.01% or less,
• Cr:
• 0.01% to 2.00%,
• Al:
• 0.001% to 0.100%,
• N:
• 0.01% or less, and
• a balance consisting of Fe and inevitable impurities;
• and
• a microstructure in which a volume fraction of martensite at a depth of 1 mm from a surface of the abrasion-resistant steel plate is 90% or more, and a prior austenite grain size at the mid-thickness of the abrasion-resistant steel plate is 80 μm or less,
• wherein hardness at a depth of 1 mm from the surface of the abrasion-resistant steel plate is 460 to 590 HBW 10/3000 in Brinell hardness, and
• a concentration [Mn] of Mn in mass % and a concentration [P] of P in mass % in a plate thickness central segregation area satisfy the following Expression (1):
• 0.04[Mn]+[P]<0.50 (1).