PrintRECOMMEND. Please check our Terms and conditions mainly for engineering standards in electronic (PDF) format. Https://Www.En-Standard.Eu DIN 5464:2010-03 Straight-sided splines - Heavy series The latest, up-to-date edition. Intertek Inform DIN5461 1965 SplineShaftConnectionWithStraightFlanks | PDF
The PDF will clarify that serrated flanges provide "locking" action against hard steel surfaces. Non-serrated flanges are used for soft materials (aluminum, plastic) or where the surface must not be scratched. din 5464 standard pdf
If you are sourcing parts based on this standard, ensure your machine shop has access to the official DIN 5464 PDF to guarantee the correct tolerances are met. PrintRECOMMEND