CONTENTS

Production, Structure, Properties

Matar S. F., Solozhenko V. L. First principles search for novel ultrahard high-density carbon allotropes: hexagonal C₆, C₉ and C₁₂. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3

Devin L. М., Bezhenar M. P., Rychev S. V. Features of measuring the modulus of elasticity and decrement of vibration of polycrystals of superhard materials using the dynamic method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

14

Sun Junlong, Zhao Weifu, Li Zhizhen, Li Bin, Liu Changxia. Effect of Al₂O₃ and Yb₂O₃ on mechanical performances and thermal shock behaviors of zirconia composites prepared by SPS. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

22

Investigation of Machining Processes

Das Manojit, Parimanik Soumya R., Mahapatra Trupti Ranjan, Mishra Deba­dutta, Sahu Dilip Kumar. Characteristics, machinability modeling, and machining performance improvement of graphene reinforced Al-MMC using CRSM and Utility method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

35

Sokhan’ S. V., Voznyy V. V., Sorochenko V. H., Hamaniuk M. P. Diamond grin­ding of ceramic balls with a circular feed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

65

Tools, Powders, Pastes

Smokvyna V. V., Lavrinenko V. I., Ilnytska H. D. The defectiveness of synthetic diamond grains of low strength – a disadvantage and a positive in the case of their use in a grinding tool. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

80

Letters to the Editor

Kvasnytsya V. M. Мain morphological varieties of diamond cubes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

92