INVESTIGATIONS OF INITIATION OF INTERCRYS TALLINE FATIGUE CRACKS OF INTERSTITIAL-FREE (IF-) STEELS

While investigation the fatigue strength of interstitial free steels, intercrystalline fatigue cracks have occurred as a damage which could reduce the application range of this material, being well-known for it s excellent depth drawing features. Through metallographic examination the known causes of the damage like formation of grain cover tertiary zementit of precipitations on the grain boundaries could be excluded. In this paper investigation results are represented which are receive d through high-resolution analyses techniques (TEM, AES).