Shuba, RomanZenotchkine, MishaChen, I-WeiKim, Joo-Sun2023-05-232023-05-232001-04-012004-11-28https://repository.upenn.edu/handle/20.500.14332/41111R-curves of single-phase Y- and Ca-containing α-SiAlON ceramics have been measured. They range from flat ones for fine-grain ceramics to pronounced rising ones when large elongated grains are present. The highest toughness measured reached 11.5 MPa∙m1/2 over a crack extension of about 1000 μm.Article