A few secrets of the metallurgist simply told

by Gerald W. Hinkley

COBALT.

The valuable effect of cobalt is claimed to be that it increases the red hardness of high speed tool steel, enabling the steel to cut at a higher speed. However, this element much resembles nickel, which has been largely condemned as not being a desirable ingredient for high speed tool steels, because it has the effect of making the edge of the finished tool soft or "leady".

URANIUM, TITANIUM AND ALUMINUM.

These elements are generally classed as scavengers, although recently important claims have been advanced for their effect upon the physical properties of steel. This is especially true for the first two. In present practice, however, they are used almost entirely as deoxidizers or cleansers, and are added to the metal for this purpose only.