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Membrane separation technology has played an enormous role in water treatment. However, the surface of the separation membrane has low wettability, and it is easy to cohere with oil droplets during the oil-water separation process, which affects the efficiency of water treatment. To improve its separation property, this article reports the continuous deposition of tannic acid (TA) titanium ([Ti.sup.IV]) complex interconnected networks with high adhesion and long-term stability on the surface of polypropylene (PP) membranes to achieve oil-water separation. The hydrophilic TA-Ti nanostructured coating shows high adhesion and long-term stability on non-polar surfaces of the PP membrane. Notably, after modification, the membrane can be used to separate hexadecane-in-water emulsions under gravity force, with a separation efficiency of over 99% and a water flux of 227 L[m.sup.-2] [h.sup.-1]. Compared with some membranes modified with polyphenols, this easy-to-prepare TA-Ti@PP membrane can achieve better separation performance with only gravity actuation. Furthermore, the modified membrane has superior reusability and excellent chemical stability (salt/acid/alkali resistance), and it has great potential in the field of oil-in-water and wastewater treatment. KEYWORDS gravity-driven separation, hydrophilicity, PP membranes, stable coating, 1 | INTRODUCTION With the rapid advancement of industrialization, the safety of water resources has become a global concern. Because of the continuous occurrence of oil spills at sea, a [...]

Piezoelectric Pb(Zr, Ti)[O.sub.3] (PZT) thin films were directly deposited on cantilever-shaped titanium substrates and evaluated for their piezoelectric properties and actuator performance. Because of the small difference in the thermal expansion coefficient between the PZT and the substrate, and the mitigation of the residual stress, large piezoelectric properties could be obtained for PZT/Ti unimorph actuators. X-ray diffraction measurements clearly revealed that the PZT thin films have a polycrystalline perovskite structure with a random orientation. Observations using a scanning electron microscope (SEM) demonstrated that PZT films, which were 3.8 [micro]m thick, were densely deposited on Pt-coated Ti substrate without pores or cracks. The polarization-electric field (P-E) hysteresis of the PZT film clearly indicates ferroelectricity. The piezoelectric properties of the PZT films were evaluated from the tip displacement of PZT/Ti unimorph cantilevers. Simplified transverse piezoelectric coef ficients ([e.sup.*.sub.31] = [d.sub.31]/[s.sup.E.sub.11], where [d.sub.31] and [s.sup.E.sub.11] are piezoelectric coefficient and elastic compliance, respectively) were measured, which ranged from -3.6 to 4.3 C/[m.sup.2]--about three times larger than those of the PZT thin films deposited on stainless-steel substrates. Measurement of resonant frequencies of the cantilevers shows a clear dependence on the cantilever length, which obeys the theoretical equation. This indicates that these cantilevers can be reliably applied as sensors and actuators in a resonance mode. [2008-0100] Index Terms--Microactuators, Pb(Zr, Ti)[O.sub.3] (PZT) ceramics, piezoelectricity, thin-film devices.

Cold spray has been developed recently to be used as an additive manufacturing technology in order to fabricate bulk components. Residual stresses are known to build up in coatings made [...]

Traditional airframe primary structure is fabricated from wrought product forms that are transformed by machining, forming, and joining into structural components. These individual parts are assembled together by fasteners to create the airframe. Significant cost and cycle-time savings can be achieved by switching from multipiece builtup assembly to a single-piece net shape casting. The reduction in number of discrete parts provides a significant reduction in both direct and indirect costs. In particular, the inherent low material costs and excellent producibility characteristics of cast metallic parts may provide a significant contribution to the goal to reduce acquisition costs. Under the program reported herein, and in conjunction with a casting vendor, prototype titanium (Ti-6Al-4V) cast airframe components were designed and fabricated. The typical overall dimensions of each casting are 50 inches X 40 inches X 30 inches, and weigh approximately 190 pounds per casting. The castings were modeled on generic aircraft fuselage structure, that incorporated smooth inner moldline surface and integral webs and keels, capped by a T-element, web stiffeners, access holes, and other detail features. Multiple castings are joined to create the airframe structure. A rapid prototyping method was utilized to create the pattern, which eliminated the requirement for expensive metal tooling. The prototype castings successfully demonstrated the producibility of this generic airframe structure. [DOI: 10.1115/1.1494099]

Titanium-supported titania-based photoelectrodes were prepared either by sol-gel processes or by thermal oxidation. Catalytic activities and stabilities of these photoelectrodes were monitored by photooxidizing formic acid in aqueous NaCl during three successive experiments under identical conditions. Although electrodes coated with either titania (higher activity) or zirconia-titania (lower activity) and heated at 300 [degrees] C were less active initially than similar electrodes heated to higher temperatures, electrodes heated at 300 [degrees] C were more stable. Activities of titania electrodes were increased by depositing the titania at a higher withdrawal speed (21.5 versus 1.5 cm [min.sup.-1]) and by depositing more layers of titania. Stabilities of multilayer electrodes were improved by depositing the sol faster. Applying positive electrical potentials across electrodes also increased their activities. In particular, while activities diminished considerably in relatively high concentrations of NaCl if no potential was present, activities decreased only slightly under an electrical field. Activities of photoelectrodes prepared by heating metallic titanium plates at 300 [degrees] C were low. Activities of photoelectrodes prepared by heating titanium at 500 [degrees] C (giving a rutile coating) were similar to activities of photoelectrodes prepared by sol-gel techniques, but only when potentials were applied.

Around the world, people are living longer with more active lifestyles thanks to continuing advancements in medical technology. This evolution in technology stems from the development of sophisticated metals and [...]

Automotive materials are at the heart of our spring issue, with a timely update on thixoforming and some highlights from Jaguar, Honda, Audi, and Ford's journey into the automotive aluminum [...]

Byline: S. Ramesh, L. Karunamoorthy, V.S. Senthilkumar, K. Palanikumar Titanium is a material which is used in aerospace and other industries is difficult to machine. Due to the growing acceptance of titanium in many industries, near-nett shape of these materials by machining cannot be eliminated fully. There are problems encountered when machining titanium in shops working with aircraft alloys. Machining of titanium alloys requires cutting forces slightly higher than those needed to machine steels, but these alloys have metallurgical characteristics that make them more difficult to machine than steels of equivalent hardness. The beta alloys are the most difficult titanium alloys to machine. This paper discusses the study of metallurgical and microstructure analysis of Ti-6Al-4V alloys. Experiments were carried out using two different inserts having different coating methods (PVD and CVD) and different nose radius (0.8 mm and 1.2 mm). The performance of machining has been studied in terms of cutting force, tool wear and surface finish.

COLD SPRAYING OF ARMSTRONG PROCESS TITANIUM POWDER FOR ADDITIVE MANUFACTURING D. MacDonald, R. Fernandez, F. Delloro, and B. Jodoin Titanium parts are ideally suited for aerospace applications due to their [...]

Warm spraying was developed by NIMS, in which powder particles are accelerated and simultaneously heated and deposited onto a suitable substrate in a thermally softened solid state. In this study, [...]

A cryogenic titanium machining process, planned for use in the production of Lockheed Martin Aeronautics Co.'s (Bethesda, Md.) F-35 Lightning II stealth fighter, debuted at the 2010 International Manufacturing Technology [...]

Scientist Robert Jaffee made significant contributions to the field of electric power technology during his tenure as head of the Electric Power Research Institute's Materials Support Group from 1975 up to the time of his death in Nov 1991. A titanium expert, Jaffee was a strong proponent of the use of the metal for utility applications. He believed that titanium possesses the important features that steel lacks in order to become an ideal material for steam turbine rotor blades.