Novel Low-temperature Solid-carburizing Using C60 Fullerene for Austenitic Stainless Steel SUS316L

In this study, the full potential of C-60 fullerene for use in the low-temperature solid-carburizing of SUS316L stainless steel is demonstrated. The carburizing of this austenitic stainless steel with C-60 was conducted in a vacuum atmosphere without any surface activation treatment of the specimen surfaces. The uncarburized SUS316L had the lattice parameter of approx. 3.5963 +/- 0.0001 angstrom and the Vickers hardness of 172 MPa measured by the Nanoindentation method. After carburizing at 475 degrees C for 200 h, the lattice parameter of the specimen surface was approx. 3.6545 +/- 0.0001 angstrom and the Vickers hardness was approx. 742 MPa. After carburizing at 500 degrees C for 100 h, the lattice parameter of the specimen surface was approx. 3.6592 +/- 0.0002 angstrom and the Vickers hardness was approx. 837 MPa. These results are comparable to those obtained by low-temperature gas- and plasma-carburizing reported in previous works.