|
Fig.4: Micrography of NIPRE on steel AISI H11 |
The chemical nobility is not the only single value considered, which brought us to realize a protective layer of Magnetite (Fe3O4).
Very important are also the data related to the oxide increase rate, its compactness, its homogeneity. All these factors are showed in the increase velocity rate of the oxide, which is inversely proportional to the degree of protection:
For the experiment we treated different cylindrical specimen in AISI HI 1with NIPRE. Those have been previously hardened and tempered at 42-44 HRC and put in a liquid solution of a primary alloy of Al in a melting pot of Al203 at 735°C. The micrographies of NIPRE layer are showed below: |
NIPRE®
