Mechanical properties coatings

Coating mechanical properties enhancement Potential cutting edge geometry change... 

Latella, B.A., Gan, B.K., Davies, K.E., Mckenzie, D.R., Mcculloch, D.G., 2006. Titanium nitride/vanadium nitride alloy coatings mechanical properties and adhesion characteristics. Surf Coat Technol 200, 3605-3611. 

Veli-Matti T. (2001) Amorphous carbon as a bio-mechanical coating-mechanical properties and biological applications. DiamondRelatMater 10 153—160. 

SOI (silicon on insulator) structures, 329 sol-gel coatings, mechanical properties of abrasion, 308 adhesion, 306 fracture toughness, 305 hardness, 302 pencil hardness, 305 stress, 297... 

Coating mechanical properties can be affected by the degree of cure, aging effects, and ambient conditions (e.g. temperature and humidity), making it difficult to establish a useful database. Moreover, organic coatings are viscoelastic, so that their properties depend on strain rate and temperature. A complete treatment of viscoelastic theory is beyond the scope of this chapter, and the interested reader is referred to Chapter 12 of this volume for a more complete discussion. The reader may also wish to consult refs. [1,2], which are review articles of transient and dynamic methods of coating characterization. 

Symposium Series 790, Film Formation in Coatings Mechanisms, Properties, and Morphology, T. Provder and M. Urban, Eds., Am. Chem. Soc., Washington, DC, 2001, Chapter. 14. 

Stress can build up in a coated plastic part and can affect coating mechanical properties. Stress can accumulate during film formation and from variation in relative humidity and/or temperature (33). Even differences between thermal expansion coefficients of the substrate and the coating can induce stress. The dissipation of accumulated stresses is key to avoiding premature system failure. 

JL Courier. Mar resistance of automotive coatings I. Relationship to coating mechanical properties. J Coatings Technology 69(866) 57-63, 1997. 

The Institute has many-year experience of investigations and developments in the field of NDT. These are, mainly, developments which allowed creation of a series of eddy current flaw detectors for various applications. The Institute has traditionally studied the physico-mechanical properties of materials, their stressed-strained state, fracture mechanics and developed on this basis the procedures and instruments which measure the properties and predict the behaviour of materials. Quite important are also developments of technologies and equipment for control of thickness and adhesion of thin protective coatings on various bases, corrosion control of underground pipelines by indirect method, acoustic emission control of hydrogen and corrosion cracking in structural materials, etc. 

The first commercial PPS process by Phillips synthesized a low molecular weight linear PPS that had modest mechanical properties. It was usehil in coatings and as a feedstock for a variety of cured injection-molding resins. The Phillips process for preparing low molecular weight linear PPS consists of a series of nucleophilic displacement reactions that have differing reactivities (26). 

A reasonably close match of thermal expansion of the coating and substrate over a wide temperature range to limit failure caused by residual stresses is desired for coatings. Because temperature gradients cause stress even in a weU-matched system, the mechanical properties, strength, and ductUity of the coating as well as the interfacial strength must be considered. 

The microstmcture and imperfection content of coatings produced by atomistic deposition processes can be varied over a very wide range to produce stmctures and properties similar to or totally different from bulk processed materials. In the latter case, the deposited materials may have high intrinsic stress, high point-defect concentration, extremely fine grain size, oriented microstmcture, metastable phases, incorporated impurities, and macro-and microporosity. AH of these may affect the physical, chemical, and mechanical properties of the coating. 

L. W. Hill, Mechanical Properties of Coatings, Federation of Societies for Coatings Technology, Philadelphia, Pa., 1987. 

Layered Structures. Whenever a barrier polymer lacks the necessary mechanical properties for an appHcation or the barrier would be adequate with only a small amount of the more expensive barrier polymer, a multilayer stmcture via coextmsion or lamination is appropriate. Whenever the barrier polymer is difficult to melt process or a particular traditional substrate such as paper or cellophane [9005-81-6] is necessary, a coating either from latex or a solvent is appropriate. A layered stmcture uses the barrier polymer most efficiently since permeation must occur through the barrier polymer and not around the barrier polymer. No short cuts are allowed for a permeant. The barrier properties of these stmctures are described by the permeance which is described in equation 16 where and L are the permeabiUties and thicknesses of the layers. 

Exterior durability. Corrosion control. Mechanical properties. Architectural coatings. Product coatings. 

Because of the much larger volume of single products, there have been more intensive studies of the mechanical properties of mbber, plastics, and fibers in the past than of coating where the volume of individual products is generally relatively small. However, the mechanical property requirements of films for various coating appHcations and how to vary composition in order to achieve these needs is under investigation. 

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