Stainless steel fiber

Recommended materials of constmction for pipes, tanks, and pumps handling citric acid solutions are 316 stainless steel, fiber glass-reinforced-polyester, polyethylene, polypropylene, and poly(vinyl chloride). At elevated temperatures, 304 stainless steel is not recommended (Table 8). 

Stainless steel fibers have attracted widespread attention. They are manufactured with diameters from 4 to 25 pm and lengths from 3 to 8 mm. 

Micrograph of sintered stainless steel fiber felt used as DL (reference bar indicates 100 pm). (Reprinted from J. Liu et al. Journal of Power Sources 133 (2004) 175-180. With permission from Elsevier.)... 

An interesting application involves the use of very fine (15 p,m) stainless steel filament as a conductive filler in a thermoplastic resin for electromagnetic shield ing. According to Nippon Steel and Nippon Seisen Co., who developed this product called Esbarrier, 4-10 wt% of stainless steel fiber provides an effective shielding of 40-50 dB at 100 MHz. 

Ho et al. used a packed-bed reactor and a series of 316 stainless steel fiber an-ode/cathode pairs to decompose cyanide-containing effluent [41]. The cyanide destruction process was enhanced by the presence of metal ions, which led the authors to treat a copper cyanide effluent. The cyanide concentration was decreased from an initial concentration of 1400ppm to less than 20 ppm within a 4-20 h time period at an energy consumption of 5 -13 kW h/kg CN. At a CN/Cu ratio of 4.6 most of the copper was deposited on the cathode while some was converted to the divalent form and deposited on the anode surface as an oxide. 

Stainless steel fibers, produced by the bundle drawing process, are used for seals, for sound attenuation, for antistatic finishes or as filter materials. 

An important application field for stainless steel fibers is the textile sector, in which 0., i to 6% of these fibers are incorporated to endow carpets, protective clothing etc. with an antistatic finish. A further application is protection against electromagnetic pulses, interference and charging. Tungsten fibers with a diameter of 12 pm are used for boron or SiC deposition and as light bulb filaments. Furthermore, metal fibers are used in the filtration of polymer melts and corrosive liquids, as well as for electrodes with high surface areas. 

Different grades of chopped low-carbon steel fibers are used as reinforcements and friction enhancers in formulations. Steel fibers have good reinforcing properties and thermal resistance but high density, poor corrosion resistance, and high thermal conductivity. Chopped stainless steel fibers have found limited application in friction materials and backing layers. Some manufacturers have developed annealed and softer grades of steel fiber to reduce rotor and drum wear. 

For EMI shielding applications, numerous processes are used, some require conductive fillers. These applications include parts molded with conductive filler and conductive paints. Conductive fillers used in commercial applications include aluminum, silver, nickel, and copper flakes and powders, stainless steel fibers, and fibers and flakes coated by nickel and silver. Thermoplastic compounds can provide up to 65-70 dB of electromagnetic noise attenuation but obtaining values over 45 dB is difficult. Static dissipative compounds (ESD) are mostly produced with carbon black which accounts for approximately 90% of the market but many other fillers are also used. 

Typical fillers glass fiber, carbon fiber, aramid, antimony trioxide, zinc borate, stainless steel fiber, graphite, nickel coated graphite, aluminum flakes, metallized glass... 

Typical concentration range stainless steel fiber - 1-7 wt%, 30 wt% or more graphite, 15-50 wt% carbon black for conductive materials, glass spheres and fibers up to 70 wt%, carbon fiber - 20 wt%, silicon oxide and silicates up to 40 wt%, LCP up to 30 wt%, wollastonite - 40 wt% (can be used in conjunction with glass fiber,copper/polyamide-11 composite was made with 90 wt% spherical copper powder ... 

Typical concentration range generally >40 wt% calcium carbonate, calcinated kaolin, talc - 20-40 wt% carbon fiber 5-30% (depending on aspect ratio) " titanium dioxide - 1 wt% (occasionally concentrations of 10 wt% are found in thin sections) " ferromagnetic powder - up to 90 wt% " stainless steel fiber - 2-3 wt% " nickel fibers for magnetic properties -10-30% starch in biodegradable products - 4-8 wt% ... 

Figure 19.9. Surface spraying with white-hot stainless steel fibers. [Adapted, by permission, from Knowles J, Polym. Paint Col. J.y 185, No.4366, 1995, 26-7.]...

Figures 19.9 and 19.10 show two unusual applications of fillers in coatings. Figure 19.9 shows a schematic diagram of the surface of metal (e.g., a pan) on which white-hot particles of stainless steel fibers are sprayed to prepare the surface for a nonstick coating. In the past, these coatings were known to have a limited durability. Durability could be increased by a change to the surface through welding the fibers to the surface.

Bag filters are traditionally used for very fine-particle collection. The filtering media are either woven textile or nonwoven paper or fiber mats. In the present case, the filtering media should be chosen in materials both compatible with the processed fluids (especially for antisolvent processes where the filter is contacted with SCF and organic solvents) and acceptable for drug manufacture. We currently tested various filter types woven or nonwoven polymer (like PTFE or polyamides) fibers to form bags or paper bags (as for vacuum cleaners), woven stainless-steel fibers to from a disk, or filter paper supported by a sintered disk at the bottom of a basket at a smaller scale ceramic filters can also be considered favorably. 

Electrafil . [Akzo Engineering Plastics] PPO, nylon, ABS, PBT, PET, PPE, PC, PP, PE, PS, aceud, polyuretiume, PES, Pl K, polyetherimide, PPS, ETI, or polysulfone fflled with carbon, stainless steel fiber, lubricants static dissipative and conductive thennoplastics. 

Fig. 5.18 Schematic depiction of the crack stopping mechanism of steel fibers in a refractory. Photographs of some typical stainless steel fibers for the reinforcement of refractories (courtesy RIBTEC, Gahanna, OH, USA).

FEL 06] Feller J.F., Roth S., Bourmaud A., Conductive polymer composites electrical, thermal, and rheological study of injected isotactic poly(propylene)/long stainless-steel fibers for electromagnetic interferences shielding . Journal of Applied Polymer Science, vol. 100, pp. 3280-3287,2006. 

There are a range of conductive polymers on the market that are based on metal fillers such as aluminum flake, brass fibers, stainless steel fibers, graphite-coated fibers, and metal-coated graphite fibers. However, the most cost effective conductive filler is carbon black. Mention should also be made of... 

LNP Corporation offers conductive plastics with fillers such as aluminum flakes, nickel-coated fibers, stainless steel fibers, and carbon fibers in a range of engineering polymers including nylon-6,6, polycarbonate, ABS, PPS, and PEEK. The company s 40% flake-filled polycarbonate is used for microprocessor covers in mainframe computers and nickel coated fiber-filled PEEK for avionic enclosures. 

A 10% stainless steel fiber-filled ABS, produced by Mitech Incorporated under the tradename Magnex DC is used to shield electronic components in Xerox s Model 2100 laser printer. Mitech also produces a flame retardant stainless steel fiber-filled ABS for large interior covers. 

Fishbane, B.M. and Pond, R.B. 1977. Stainless steel fiber reinforcement of polymethylmethacrylate, Clin. Orthop., 12S, 490-498. 

Another factor that influences the value of pc is the aspect ratios of the metallic filler. Metal fibres, metal-plated glass fibers, and metal flakes can significantly lower the concentration required to achieve isotropic conduction as compared to spherical powders [3]. Values of pc as low as 1 vol % have been reported with stainless steel fibers having an aspect ratio of 750 [37]. 

STAINLESS STEEL FIBER ORGANIC MATRIX COMPOSITES FOR CRYOGENIC APPLICATION ... 

Stainless Steel Fiber Organic Matrix Composites for Cryogenic Application... 

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