SURFACE MODIFICATION OF A METAL INTO A THICK CERAMIC LAYER AND A MODEL FOR ANALYSING THE INCREASED HARDNESS

• Published in: Journal of Ceramic Processing & Research Vol. 8; no. 3; pp. 191 - 194
• Main Authors: Emura, S, Nunogaki, M, Nakata, Y
• Format: Journal Article
• Language: English
• Published: 세라믹연구소 01.01.2007
• Subjects: 재료공학
• ISSN: 1229-9162; 2672-152X

Surfaces of metallic Ti were modified with thick layers of TiC by reactive plasma processing. The carbonised surfaces consisted of mixed layers of TiC and metallic Ti. TiC grains grew on the Ti substrate with island forms. The metal Ti acted as a 'paste' between the growing TiC grains. The hardness of the modified surface layers increased with processing temperature. The hardness reached 5000 kg/mm2 at a processing temperature of about 1300 C, which was a value comparable to bulk TiC. Analysis of the XAFS spectrum and the diffraction profiles for the fabricated layers showed a reduction of the Ti-Ti distance from a distance of 3.07 Angstrom for the bulk TiC to 3.025 Angstrom. Using the results of the local structures around a Ti element by XAFS analysis, the abnormal hardness of the newly fabricated TiC was elucidated by an analytical model. 15 refs.