Composite surface treatment

The CRC-Elsevier materials selector , 2nd edition, N.A. Waterman, and M.E Ashby CRC Press (1996) ISBN 0412615509. (Now, also available on CD-ROM). Basic reference work. Three-volume compilation of data for all materials includes selection and design guide. The Materials Selector is the most comprehensive and up-to-date comparative information system on engineering materials and related methods of component manufacture. It contains information on the properties, performance and processability of metals, plastics, ceramics, composites, surface treatments and the characteristics and comparative economics of the manufacturing routes which convert these materials into engineering components and products. 

Information on fibers applicable to different materials of construction and use that relates to compositions, surface treatments, performances, processing, and terminology follows ... 

Keywords plasma/polymer/vacuum ultraviolet photochemistryAvetting/adhesion/ composites/surface treatment/free radical/bonding. 

After practical use, the energy density of the battery is doubled from 180 to 350 Wh/L by the development of the various technologies such as active material composition, surface treatment, and additives. This battery has been put to practical use for the power supply for the power tool by the improvement of the high output performance. The AA size and AAA size batteries that are compatible with a dry cell have been also put to practical use. This battery system has been put to practical use for HEV (hybrid electric vehicle) by the establishment of the battery management technology... 

The morphology is complex. It depends on composition, surface treatment of filler, and compounding technology. The standard commercial product has a dispersed morphology. For special applications filler encapsulation by elastomer can be obtained. 

Unidirectional composite of Monsanto s polyimide composite matrix designated Skybond 710 and Hercules high tensile strength carbon fiber reinforcement, composite surface treatment was mild abrasion. 

We now come to a very important topic, namely, the thermodynamic treatment of the variation of surface tension with composition. The treatment is due to Gibbs [35] (see Ref. 49 for an historical sketch) but has been amplified in a more conveniently readable way by Guggenheim and Adam [105]. 

Numerous variations in composition, appHcation method and surface treatment, and properties of Mg(OH)2-containing flame-retardant fillers are disclosed in the patent Hterature (92—95). Smoke-suppressant foams incorporating Mg(OH)2 are useful as roof insulation slabs (96). Mg(OH)2 is contained... 

Exact si2ing of mica products coupled with surface treatment procedures have led to a greater use for wet ground mica in plastic compositions, particularly automobile bodies. These quahty products demand a high dollar value. 

More than 95% of current carbon fiber production for advanced composite appHcations is based on the thermal conversion of polyacrylonitrile (PAN) or pitch precursors to carbon or graphite fibers. Generally, the conversion of PAN or pitch precursor to carbon fiber involves similar process steps fiber formation, ie, spinning, stabilization to thermoset the fiber, carbonization—graphitization, surface treatment, and sizing. Schematic process flow diagrams are shown in Eigure 4. However, specific process details differ. 

It is critical that surface treatment conditions be optimized to composite properties since overtreatment as well as undertreatment will degrade composite properties. Typically composite interlaminar shear strength (ILSS), in-plane shear, and transverse tension ate used to assess the effectiveness of surface treatment. More recently damage tolerance properties such as edge delamination strength, open hole compression, and compression after impact have become more important in evaluating the toughness of composite parts. 

The phases and their proportions present ia hardened amalgam are controlled by many factors. The composition of the alloy the size, shape, and size distribution of the particles the thermal history of the cast ingot and the comminuted alloy and the surface treatment of the particles are some of the factors for which the manufacturer is responsible. The tooth cavity preparation and the mixing, compacting, and finishing techniques of the dentist can make the difference between satisfactory and unsatisfactory restorations, even with the best of alloys. A minimal amount of residual mercury and porosity are needed to obtain the most serviceable restorations (138). 

Cassie [39] extended Wenzel s treatment to composite surfaces. His treatment can be applied to a rough surface incompletely wetted by a liquid so that it consists of an area fraction f wetted and /2 unwetted surface. Then ... 

Surface treatment of the composite can have a significant effect on adhesion. Surface treatment enhances one or more of the mechanisms described previously. Wu et al. [15] studied the effects of surface treatment on adhesive bonding for AS-4/APC-2 laminates. They found that the greatest bond strength was achieved from acid etching and plasma etching the composite surface. Table 1 summarizes the various surface treatments that were evaluated. 

Wu, S.Y, Schuler, A.M. and Keane, D.V., Adhesive bonding of thermoplastic composites 1. The effect of surface treatment on adhesive bonding. 9th Int. SAMPE Symp., Oct. 13-15, 1987. 

As shown in Table 10, the surface modifications cause noticeable increases of the characteristic values of composites, depending on the fiber, matrix, and type of surface treatment used. 

Aside from type of claim (fiber dominant or interfacet matrix dominant), the efficiency of surface treatments depends noticeably on the fiber content within the composite. At a fiber content of 30 vol%, tensile strength increases by 10% and shear strength increases by about 100% (Fig. 12). In contrast to modified fibers where shear strength rises with increasing fiber content, the chart, after having reached a maximum, shows a... 

Figure 12 Dependence of tensile strength and shear strength of PP-flax composites on fiber content and on surface treatment. (-) untreated flax (-) flax pretreated with hostaprime HC5.

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