Previous work on Georgia plantations has provided useful data about life on the large plantations on barrier islands. More recent work on small to mid-sized plantations reveals that slaves’ acquisition of ceramics may reflect more of their own decisions on what was purchased and what was used. Coarser ware frequencies indicate food preparation and storage in the slave quarters. Porcelain was of...

Rotary ultrasonic machining (RUM) is a relatively low cost and environmentally benign process for machining of advanced ceramics. Much effort has been made to theoretically and experimentally investigate material removal rate, surface roughness, and tool wear in RUM. However, there is no report on systematic study of edge chipping in RUM drilling of ceramics. This paper presents the results of ...

To physicists and engineers, ceramics represent materials demonstrating excellent strength and hardness, materials that can serve as electrical insulators or conductors, some of them being able of a high-temperature superconductivity. To researchers working in archaeology and art history, ceramics mean objects such as figurines, tiles and tableware helping understanding cultures and technologie...

Lead-free 0.98(Na0.5K0.5)NbO3-0.02Ba(Zr0.52Ti0.48)O3 [0.98NKN-0.02BZT] ceramics were fabricated by the conventional mixed oxide method with sintering temperature at 1,080°C to 1,120°C. The results indicate that the sintering temperature obviously influences the structural and electrical properties of the sample. For the 0.98NKN-0.02BZT ceramics sintered at 1,080°C to 1,120°C, the bulk density i...

Three kinds of near-field microscopy imaging mode including SEAM (Scanning electron acoustic microscopy), PFM (Piezoresponse force microscopy) and SPAM (Scanning probe acoustic microscopy) have been developed to investigate domain structures of ferroelectric ceramics, crystals and thin films in our studies. The domain imaging mechanisms are presented individually in three imaging modes. Sub-sur...

nanocrystalline hydroxyapatite was precipitated from calcium hydroxide and phosphoric acid. effects of precipitation temperature and different calcium to phosphate ratios (ca/p) on the obtained powders were investigated. characteriza-tion of the powders was performed using xrd and ftir spectra, scanning electron microscopy, and transmission electron microscopy. increase in precipitation tempera...

In this paper, single-phase multiferroic ceramics of (1 x) BaTiO3 x BiFeO3 (BT x BFO) were synthesized by solid-solution method in the wide range of material composition (x1⁄4 0.025 – 1.0). The changes in crystal structure were confirmed via X-ray diffractions (XRD) and atomic pair distribution functions (PDFs). The room-temperature ME coupling was found to exhibit significant magnitude in the ...

A new scheme is proposed to measure the electro-optical (EO) and converse-piezoelectric (CPE) coefficients of the PMN-PT ceramics simultaneously, in which the PMN-PT ceramics acts as the guiding layer of a symmetrical metal-cladding waveguide. As the applied electric field exerts on the waveguide, the effective refractive index (RI) (or synchronous angle) can be effectively tuned from a selecte...

This paper studies the AC conductivity and permittivity of hydroxyapatite (HA)-based ceramics from 0.1 Hz-1 MHz at temperatures from room temperature to 1000 degrees C. HA-based ceramics were prepared either as dense ceramics or in porous form with interconnected porosity and were sintered in either air or water vapour. Samples were thermally cycled to examine the influence of water desorption ...

Clinical cases show that zirconia restoration could happen fracture by accident under overloading after using a period of time. The purpose of this study is to research mechanical behavior and predict lifetime of dental zirconia ceramics under cyclic normal contact loading with experiments. Cyclic normal contact loading test and three point bending test are carried on specimens made of two bran...