EN 10083-1 specifies a minimum yield strength of 370 MPa for C45 round steel. This medium-carbon grade (0.42-0.50% C) achieves its strength through hot rolling and optional heat treatment. The yield strength ensures it can withstand static loads in machinery components like gears and axles without permanent deformation. Testing involves tensile specimens taken from the round bar, with results averaged across three samples to ensure consistency. Higher yield strengths (up to 500 MPa) are achievable via cold drawing.