I conduct a microstructure experiment on AISI 1010 low carbon steel, and the result show that pearlite is more abundant than ferrite, whereas it should be the opposite.
The amount of ferrite, perlite, bainite and martensite of steels depends on the chemical composition and the heat treatment. Without knowing more details, e.g. treatment temperature, cooling procedure, furnace atmosphere and used etching reagent, one can guess what caused the reduction of the ferrite content. In addition a hardness measurement could give you additional hints.
Nevertheless, you should have a the look at the corresponding time temperature transformation diagrams of the AISI 1010. The "Atlas of Time-Temperature Diagrams for Irons and Steels" from George F. Vander Voort (ASM international) contains such a diagram for continuously cooling (see page 531 from the 1991 edition), or check 10.56042/ijems.v28i3.45776 for ttt diagram.
Frankly speaking, it looks more like something went wrong with etching. Did you use nital or something else? To be sure that the dark regions are really pearlite would be helpful to zoom-in and resolve cementite lamellae.
I agree with Jürgen and Oleksandr - you are either facing a heat treatment issue or a preparation issue. The TTT diagram referred to by Jürgen shows that semi-fast cooling can result in a mixture of bainite and ferrite and it's possible to have bainite being the dominating phase. The hardness will reveal this - or as suggested by Oleksandr you could observe the dark areas at higher magnification to decide if the structure is pearlitic (lamellar) og bainitic.
But your photos rather indicate an etching issue causing excessive pitting. Nital would be the best choise for this steel.
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