Micro-structural effect to Yield stress and yield ratio of low carbon steel.
1) No - pearlite (pearlitic)
By stating "low carbon steel" this discussion is limited to steel with less than ~0.30% carbon. A 100% pearlite microstructure would require ~0.77% carbon, therefore a 100% pearlite microstructure cannot be obtained from from a low carbon steel, and therefore a pearlite microstructure is not the best response to the question.
2) No - ferrite / pearlite
If the low carbon steel were to be slow cooled from the austenite range, the final microstructure would be ferrite / pearlite. Ferrite / pearlite microstructures are ductile, weldable, and tough, but not typically high strength.
3) Yes - TMCP / HSLA / or microalloyed
If the low carbon steel composition is modified with microalloying elements such as Nb, Ti, V, or Al and rolled within the transformation temperature range such as a thermo-mechanically controlled processed (TMCP) steel, then a high yield strength (>400 MPa).
4) Yes - quenched and tempered (Q&T) and dual phase
As mentioned by "Hamed Mirzadeh" above, the quenched and tempered and dual phased steel processing approaches can also produce high strengths. The steel is water quenched from the austenite hot working temperature to form hard, brittle martensite. Then the steel is tempered below the transformation temperature to restore ductility and toughness.
In fact grades X65, X70, X80, X100 and X120 from the specification API 5L (where the number after the X represents yield strength in ksi) all exceed the yield strength of 400 MPa (58 ksi). These grades allow for either TMCP or Q&T processing approaches.
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