Sliding element, sliding structure including the sliding element, and method for producing microscopic surface structure in the sliding element

A method for producing a microscopic surface structure in a first sliding element forming a sliding structure in cooperation with a second sliding element, the first and second sliding elements being made of metal and including sliding surfaces relatively slidable via a lubricating oil film therebetween, the microscopic surface structure including a base portion, dimples inward recessed from the base portion and separated from each other, a ratio of a sum of opening areas of the dimples to an area of the surface of the sliding element being in a range of 5% to 60%, and a peripheral portion defining the opening area of each of the dimples, the peripheral portion extending along a periphery of each of the dimples, the peripheral portion having a height smaller than a thickness of the lubricating oil film, the method comprising:

• subjecting the sliding surface of the first sliding element to blasting to form a previous microscopic surface structure which includes the base portion, the dimples and projections extending outward from the base portion and along a periphery of each of the dimples, the projections having a second height larger than the height of the peripheral portion;
• and
• subjecting the sliding surface of the sliding element to surface finishing to reduce the second height of the projections and form the previous microscopic surface structure into the microscopic surface structure.