Coated steel product

A coated steel product comprising:

• a steel product;
• and a coating layer including a Zn—Al—Mg alloy layer disposed on a surface of the steel product,
• wherein the Zn—Al—Mg alloy layer includes a Zn phase, an Al phase, and a MgZn2 phase, and contains a Mg—Sn intermetallic compound phase in the Zn phase, and
• the coating layer consists of, in terms of an average composition and % by mass:
• Zn:
• 45.00% or more;
• Al:
• more than 5.0% and less than 35.0%;
• Mg:
• more than 3.0% and less than 15.0%;
• Sn:
• from 0.01% to less than 5.00%;
• Bi:
• from 0% to less than 1.0%;
• In:
• from 0% to less than 0.5%;
• Ca:
• from 0% to less than 3.00%;
• Y:
• from 0% to less than 0.5%;
• La:
• from 0% to less than 0.5%;
• Ce:
• from 0% to less than 0.5%;
• Si:
• from 0% to less than 2.5%;
• Cr:
• from 0% to less than 0.25%;
• Ti:
• from 0% to less than 0.25%;
• Ni:
• from 0% to less than 0.25%;
• Co:
• from 0% to less than 0.25%;
• V:
• from 0% to less than 0.25%;
• Nb:
• from 0% to less than 0.25%;
• Cu:
• from 0% to less than 0.25%;
• Mn:
• from 0% to less than 0.25%;
• Fe:
• from 0% to 5.0%;
• Sr:
• from 0% to less than 0.5%;
• Sb:
• from 0% to less than 0.5%;
• Pb:
• from 0% to less than 0.5%;
• B:
• from 0% to less than 0.5%;
• and
• impurities, and
• wherein the coating layer has a chemical composition that satisfies the following Formulae 1 to 5:
• Bi+In<Sn;
• Formula 1:
• Y+La+Ce<Ca;
• Formula 2:
• 0≤Cr+Ti+Ni+Co+V+Nb+Cu+Mn<0.25;
• Formula 3:
• 0≤Sr+Sb+Pb+B<0.5;
• and Formula 4:
• 0.0034×(Al)2+0.0964×(Al)+2.4323≤(Mg)≤−0.0062×(Al)2+0.65×(Al)−0.0937, Formula 5:
• wherein, in Formulae 1 to 5, each element symbol represents a content of each element in terms of % by mass,
• wherein, in a backscattered electron image of the Zn—Al—Mg alloy layer obtained in a case in which a field of view of 1000 μm×700 μm is observed with a scanning electron microscope at a magnification of 500 times after a surface of the Zn—Al—Mg alloy layer is polished to an extent of one-half of a layer thickness, a total area proportion of the Al phase and the MgZn2 phase is 70% or more, and an area proportion of the Zn phase is 30% or less, and
• wherein, in a backscattered electron image of the Zn—Al—Mg alloy layer obtained in a case in which a field of view of 1000 μm×700 μm is observed with a scanning electron microscope at a magnification of 500 times after a surface of the Zn—Al—Mg alloy layer is polished to an extent of one-half of a layer thickness, an average value of cumulative circumferential lengths of the Al phase is less than 88 mm/mm2 and a total frequency in number of the Al phase having a circumferential length of 50 μm or more is less than 100.