The residual-stress induced failure of Ti-6Al-4V/Si3N4 joints brazed with two different Si3N4 ceramics possessing intrinsic properties was elucidated through experimental and finite-element (FE) thermo-mechanical simulations incorporating the local elasto-plastic as-received Ag-Cu-Ti filler brazing zone characterized by nano-indentation. All tested fractured mainly from due to residual stress, ...

Transparent polycrystalline ceramics exhibit improved mechanical and optical properties. However, synthesizing transparent without additives is nontrivial. Herein, we report the synthesis of two (β-Si3N4 γ-Si3N4) under high pressure temperature from a pure Si3N4 precursor with nano-/micro-dual grain sizes. Synthesized β-Si3N4 exhibited significantly enhanced Vickers hardness reaching 24.2 GPa (...

Despite the many attractive potential uses of ceramic materials as humidity sensors, some unavoidable drawbacks, including toxicity, poor biocompatibility, long response and recovery times, low sensitivity and high hysteresis have stymied the use of these materials in advanced applications. Therefore, in present investigation, we developed a capacitive humidity sensor using lead-free Ca,Mg,Fe,T...

Yb(3+)/Ho(3+) activated glass ceramics containing β-YF3 nanocrystals were successfully fabricated. The green ((5)S2/(5)F4→(5)I8) upconversion emission is dominant in the glass ceramics and is about 160 times stronger than that of the precursor glass, resulting from the partition of lanthanide activators into a low-phonon-energy crystalline lattice and the subsequent low probability of multi-pho...

in order to fabrication of transparent glass-ceramics with li-mica nano crystals, the glasses with chemical composition of 94.9 mass% li(1+x)mg3alsi3(1+x)f2 (x=0.5) with 5.1 mass% mgf2 were crystallized. the glasses were fabricated via the conventional melt-quenching technique. mica crystals were precipitated in the glass phase by later heat treatment. glass samples had glass transition tempera...

Pengzhan Sun, Renzhi Ma, Hui Deng, Zhigong Song, Zhen Zhen, Kunlin Wang, Takayoshi Sasaki, Zhiping Xu, Hongwei Zhu State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, ...

We investigate the interaction of light and gas in strongly scattering nano- and macroporous media. Manufacturing and structural characterization of ZrO(2), Al(2)O(3) and TiO(2) ceramics with different pore sizes, measurements of optical properties using photon time-of-flight spectroscopy, and high-resolution laser spectroscopy of O(2) at 760 nm are reported. We show that extreme light scatteri...

The addition of SiC or TiC nanoparticles to polycrystalline alumina matrix has long been known as an efficient way of improving the mechanical properties of alumina-based ceramics, especially strength, creep, and wear resistance. Recently, new types of nano-additives, such as carbon nanotubes (CNT), carbon nanofibers (CNF), and graphene sheets have been studied in order not only to improve the ...