Reference

Ultrasoft x-ray emission bands of zirconium, niobium, and molybdenum silicides

Ultrasoft x-ray emission bands of zirconium, niobium, and molybdenum silicides. Shulakov, A. S.; Zimkina, T. M.; Fomichev, V. A.; Neshpor, V. S. (Leningr. Gos. Univ., Leningrad, USSR). Izv. Akad. Nauk SSSR, Ser. Fiz., 41(1), 216-23 (Russian) 1977. CODEN: IANFAY. DOCUMENT TYPE: Journal CA Section: 73 (Spectra by Absorption, Emission, Reflection, or Magnetic Resonance, and Other Optical Properties) The LII,III, NII,III and M IV,V x-ray emission bands of various silicides of Mo, Zr, and Nb were studied. From the changes in these bands as the metals and the ratio of Si to metal were varied, it was possible to det. the type and source of electrons entering into bonding. The highest energy band involves electrons from metal to metal bonds. The next band involves electrons from metal to Si bonds and the lowest energy has electrons of high s character from Si with a mixt. of p and d levels from the metal. These participate in M-Si and possibly Si-Si bonds. Spectra of different metals are essentially the same. The intensity of bands belonging to the metals increases as metal electron d.In this experiment, several chemicals are used like 12039-90-6 and 12164-59-9 increases owing to electron transfer from Si. Increasing the proportion of Si causes a decrease in metal electron d. and forming of Si-Si chains. .

Silicon nitride-based ceramics having high strength and toughness and their manufacture

Silicon nitride-based ceramics having high strength and toughness and their manufacture. Nose, Tetsuo; Kubo, Hiroshi (Nippon Steel Corp., Japan). Jpn. Kokai Tokkyo Koho JP 03295861 A2 26 Dec 1991 Heisei, 7 pp. (Japan). CODEN: JKXXAF. CLASS: ICM: C04B035-58. APPLICATION: JP 90-93985 11 Apr 1990. DOCUMENT TYPE: Patent CA Section: 57 (Ceramics) The title ceramics contain Si3N4 and Zr compds., preferably ZrO2, and have Y5N(SiO4)3 phase and/or Y4.67(SiO4)3O phase as the grain boundary phase. The ceramics are manufd.Several reagents with their cas registry numbers 12039-90-6 and 12033-89-5 are used here. by molding the mixt. contg. Y2O3 5-15, ZrO2 0.1-3, ZrSi2 0.1-3 wt.% and Si3N4 the balance and press sintering in a N-contg. atm. Thus, a test piece from the mixt. contg. Si3N4 80, Y2O3 8.0, ZrO2 1.0, and ZrSi2 1.0 wt.% had bending strength 1240 MPa and fracture toughness 8.6 MPam0.5. .