ASTM A536 grade 60-42-10 is a special grade of ductile iron for USA. You can take it equal to ISO 450-10, China QT450-10, Germany EN-GJS-450-10, UK 420/12, Italy GS400-12.
According to the standard of ASTM A536, this material grade requires Tensile Strength min. 415 MPa, Yield Strength min. 290 MPa, Elongation min. 10%.
This material grade is the ductile iron used for special applications, such as pipes, fittings etc. Actually, Grade 65-45-12 is better than this grade, so many clients are using grade 65-45-12 as replacement.
This material grade has middle tensile strength, but the elongation is high, so it is strong and ductile enough, however, unless you have special reasons, otherwise, the equal grade 65-45-12 may be a better choice.
The following is the mechanical requirement to this grade.