Industrial application of AISI 4340 steels treated in cathodic cage plasma nitriding technique

Nowadays, in plastic industry, mills are used to recycle residues generated from the manufacture of plastic components. These mills contain cut blades that suffer accelerated wear, since they are continually submitted to tribological efforts. This fact reduces its useful life. In this work, a new technique of plasma nitriding, called “cathodic cage”, was investigated. This technique eliminates some problems, like restriction rings, inherent of the conventional plasma nitriding. It was used AISI 4340 steel in substitution to AISI 01 steel, normally used in the cut blades manufacture. The AISI 4340 steel was, then, nitrided by conventional and cathodic cage techniques. After this stage, commercial and nitrided cut blades were submitted to analysis of acting. The AISI 4340 steel nitrided by cathodic cage presented uniforms thickness and hardness in the nitrided layer, promoting the average increase of 58% in its useful life, when compared with commercial blades.