Quantitative Evaluation of MnS Inclusion in Rolled Steels Detected by Ultrasonic Testing

Abstract

A new testing method is proposed which may evaluate the quantity of A-type MnS inclusions in rolled steels. This method is characterized by scanning on the lattice points assumed on steel plates.
An experimental study about the performance of this method has been performed.
Results obtained are as follows.
Mean echo height (F) is correlated with the ratio (AR_c) of the projected area of inclusions to the scanning area of steels.
The pitch of the lattice points and the scanning area of steels affect the assurance of results. Therefore, in the inspection of steel frame members, it is necessary for the pitch to be at least 10mm.