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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 [...]

Wear characteristics of Al6061 composites, reinforced with short NiTi fibers, were investigated. The NiTi/Al6061 composite samples were fabricated using pressure-assisted sintering process in ambient air where the NiTi fibers are aligned unidirectional in the Al matrix. In addition, NiTi/Al6061 composite with 5 wt % SiC particulates and monolithic Al6061 and Al6061 with 5 wt % SiC particulates were processed in similar conditions. The wear tests were performed using a reciprocating tribometer in ball-on-flat configuration where the counterbody material was martensitic steel. The effects of fiber isotropy and SiC reinforcements on wear resistance were experimentally investigated in dry sliding. Wear properties of the samples were studied using an optical profiler and a scanning electron microscope analysis. The results showed that transverse NiTi fibers improve the wear resistance significantly. Samples with transverse fiber orientation show mostly abrasive wear, whereas, monolithic and parallel samples show adhesive wear mechanism. In addition, SiC reinforcements improve the wear resistance of the composite and the monolithic samples. Since the Al6061 matrix material is smeared onto NiTi fibers in a short period, all composite samples show similar frictional characteristics after certain period of running in dry sliding. [DOI: 10.1115/1.4002332] Keywords: wear mechanism, NiTi wires, fiber orientation, short fiber composites

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]

Evaluation of the fatigue life in titanium matrix composites under isothermal and thermomechanical fatigue involves various models. The dominant damage model and the life fraction model are applicable over wide a range of frequency, temperature and loads. The use of stabilized stress or strain states enhances the predictability by incorporating stress redistribution due to damage, creep, and stress relaxations over the initial loading cycles.

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 [...]

Mesoporous silica-based molecular sieves partially replaced with titanium are manufactured by templating. Titanium silicate materials exhibit catalytic activity toward oxidation of phenolic compounds and the transformation of benzene to phenol. The titanium silicate is a perfect molecular sieve catalyst in oxidizing alkanes and phenols.

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 [...]

Titanium alloy Ti-6AI-4V ELI is selected for a high-pressure drilling riser application due to its high specific strength, corrosion resistance, and favorable elastic properties. The qualification of this titanium alloy requires assessing its resistance to hydrogen embrittlement and stress corrosion cracking due to seawater with/without cathodic protection, evaluating its wear resistance against a rotating steel drill string, and studying the influence of service-induced defects on fatigue and crack growth behavior when subjected to the operating environment. The paper presents an overview of the design requirements for a titanium drilling riser, and the material properties of the Ti-6AI-4V ELI alloy proposed for this application. The paper also highlights recent efforts to merge titanium and composite technologies to develop cost-effective drilling risers. [S0892-7219(00)01001-3]

The use of titanium for manufacturing aircraft has been greatly enhanced with the use of superplastic forming and diffusion bonding methods. The manufacturing approach results in more durable products at a reduced cost. It also permits the manufacture of components with complicated geometric configurations and, combined with the finite-element method, may predict the allowable pressures and thickness distributions. A collaboration between the Los Alamos National Laboratories and Barnes Aerospace has made improvements that enable scientists to manipulate temperature and pressure parameters.

Engineers at Boeing Defense and Space Group are devising ways of joining titanium welds without using fasteners that will significantly cut down cost and weight of next generation fighter aircraft. The air frame of the futuristic F-22 USAF fighter aircraft will be built of titanium, aluminium and other materials. Titanium alone accounts for 30% of the fighter's frame, and it is difficult and expensive to manufacture because of the extensive fabrication that is required.

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 [...]