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Resistance to abrasion

It is used only as a film, and it has good resistance to abrasion and resists staining. It also has outstanding weathering resistance and maintains useful properties from — 100 to 150°C. [Pg.1017]

Phenyl groups impart resistance to temperature variations, flexibility under heat, resistance to abrasion, and compatibility with organic products. [Pg.1023]

Hardness. Glass hardness tests usually measure the resistance to abrasion by grinding or grit-blasting, resistance to scratching, or penetration by an indenter. The method to be used depends on expected service conditions. Knoop hardness (Table 4) is commonly used, because other methods usually fracture the glass. [Pg.299]

In other areas, POD has been used to improve the wear resistance of a mbber latex binder by incorporation of 25% of Oksalon fibers. Heat-resistant laminate films, made by coating a polyester film with POD, have been used as electrical insulators and show good resistance to abrasion and are capable of 126% elongation. In some instances, thin sheets of PODs have been used as mold release agents. For this appHcation a resin is placed between the two sheets of POD, which is then pressed in a mold, and the sheets simply peel off from the object and mold after the resin has cured. POD-based membranes exhibit salt rejection properties and hence find potential as reverse osmosis membranes in the purification of seawater. PODs have also been used in the manufacturing of electrophotographic plates as binders between the toner and plate. These improved binders produce sharper images than were possible before. [Pg.535]

Nitriding can impart significant wear resistance to steel surfaces, as illustrated in Eigure 8. The resistance to abrasion of an uncase hardened steel compared to that of the same steel nitrided, and the steel having a carburized case, is shown (3,17). Improvement in weight loss is related direcdy to the hardness of the case. [Pg.215]

In addition to fiber and fabric influences on abrasion resistance, chemical finishes must also be considered. Many thermosetting resins used to impart durable press characteristics to ceUulosic fabrics reduce their resistance to abrasion as a result of fiber embrittlement. [Pg.460]

Durable finishes maintain a high level of performance after laundering, dry cleaning, or both. Durable has also been used to describe resistance to abrasion. [Pg.307]

The 3M Abrasion Test (51) is used to assess the durabUity of a protective fluorochemical finish by evaluating its resistance to abrasion and wear. The surface is abraded with an AATCC crockmeter fitted with sandpaper. [Pg.309]

The decorative plastic laminates widely used for countertops and cabinets are based on melamine—formaldehyde resin (see Laminates). Several layers of phenohc-saturated kraft paper are placed in a press and a sheet of a-ceUulose paper printed with the desired design and impregnated with melamine—formaldehyde resin is placed over them. Then a clear a-ceUulose sheet, similarly impregnated with the resin, is placed on top to form a clear, protective surface over the decorative sheet. The assembly is cured under heat and pressure up to 138°C and 10 MPa (1450 psi). A similar process is used to make wall paneling, but because the surfaces need not be as resistant to abrasion and wear, laminates for wall panels are cured under lower pressure, about 2 MPa (290 psi). [Pg.328]

The compositions of the conversion baths are proprietary and vary greatly. They may contain either hexavalent or trivalent chromium (179,180), but baths containing both Cr(III) and Cr(VI) are rare. The mechanism of film formation for hexavalent baths has been studied (181,182), and it appears that the strength of the acid and its identity, as well as time and temperature, influences the film s thickness and its final properties, eg, color. The newly prepared film is a very soft, easily damaged gel, but when allowed to age, the film slowly hardens, assumes a hydrophobic character and becomes resistant to abrasion. The film s stmcture can be described as a cross-linked Cr(III) polymer, that uses anion species to link chromium centers. These anions may be hydroxide, chromate, fluoride, and/or others, depending on the composition of the bath (183). [Pg.143]

Eor the free swelling index which is also known as the cmcible swelling number (ASTM D720), a coal sample is rapidly heated to 820°C in a covered cmcible. Then the profile of the resulting char is compared to a series of standard numbered profiles (18). Eor the Roga index weighed amounts of coal and standard anthracite are mixed and carbonized, and the product coke is tested in a Roga dmm for its resistance to abrasion (89). [Pg.233]

Size consist, carbon content, resistance to abrasion, impact... [Pg.249]

Epoxy and polyester systems filled with flake glass provide a finish that is tough and resistant to abrasion. One commercial system is filled with copper flakes to provide intrinsic antifouling action. These systems are apphed at a total dry film thickness of about 625 p.m and are used on pleasure boats. [Pg.366]

The main differences in the SteUite aUoy grades of the 1990s versus those of the 1930s are carbon and tungsten contents, and hence the amount and type of carbide formation in the microstmcture during solidification. Carbon content influences hardness, ductUity, and resistance to abrasive wear. Tungsten also plays an important role in these properties. [Pg.373]

The Tribaloy aUoy T-800, is from an aUoy family developed by DuPont in the eady 1970s, in the search for resistance to abrasion and corrosion. Excessive amounts of molybdenum and sUicon were aUoyed to induce the formation during solidifica tion of hard and corrosion-resistant intermetaUic compounds, known as Laves phase. The Laves precipitates confer outstanding resistance to abrasion, but limit ductUity. As a result of this limited ductUity the aUoy is not generaUy used in the form of plasma-sprayed coatings. [Pg.374]

Fillers. Diatomite mineral fillers are used primarily (/) where bulk is needed with minimum weight increase, (2) as an extender where economy of more expensive ingredients is a factor, or (3) where the stmcture of the particle is important. In other appHcations, diatomite can add strength, toughness, and resistance to abrasion, or it can act as a mild abrasive and polishing agent (see Abrasives). [Pg.58]

Extruded applications of nylon, other than film and monofilcunent, are less commonly encountered because of the low melt viscosity of the polymers. Uses include cable sheathing which requires resistance to abrasion and/or chemical attack, flexible tubing for conveying petrol and other liquids, piping for chemical... [Pg.503]

General advice on the suitability and degree of resistance of glove materials are summarized in Table 13.12. In all cases, however, in addition to the necessary mechanical properties (i.e. resistance to abrasion, blade cut resistance, tear resistance and puncture resistance rated according to European Standard EN 388), consideration should be given to the resistance to the specific chemicals involved. [Pg.437]

Chromium diffusion applied to a low-carbon steel produces a surface that has the characteristics of ferritic stainless steel, such as AISI446 to a depth about 0.1 mm. When diffusion is applied to a high-carbon steel, a surface rich in chromium carbides is formed. This has a hardness greater than 1000 VHN, which provides good resistance to abrasion. [Pg.101]

Abreibfestigkeit, /. resistance to abrasion. Abreibung, /. rubbing off or down abrasion attrition. [Pg.8]


See other pages where Resistance to abrasion is mentioned: [Pg.75]    [Pg.271]    [Pg.2702]    [Pg.150]    [Pg.9]    [Pg.405]    [Pg.283]    [Pg.285]    [Pg.247]    [Pg.391]    [Pg.405]    [Pg.451]    [Pg.209]    [Pg.261]    [Pg.257]    [Pg.336]    [Pg.460]    [Pg.320]    [Pg.446]    [Pg.549]    [Pg.578]    [Pg.197]    [Pg.39]    [Pg.367]    [Pg.374]    [Pg.473]    [Pg.126]    [Pg.1110]    [Pg.361]    [Pg.361]    [Pg.389]   
See also in sourсe #XX -- [ Pg.220 ]

See also in sourсe #XX -- [ Pg.181 , Pg.194 , Pg.200 ]

See also in sourсe #XX -- [ Pg.209 , Pg.225 , Pg.232 ]




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Abrasive resistance

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