| 摘要 |
PROBLEM TO BE SOLVED: To provide a free-cutting ceramics with little change of properties on ageing at a low cost. SOLUTION: This free-cutting ceramics comprises as the main component a crystalline phase of a compound oxide comprising 5 to 30 mol% of Mg as oxide, 25 to 50 mol% of 4a family element in the periodical table as oxide, and 30 to 50 mol% of Nb as oxide. |
