Nondestructive testing composites

Nondestructive Testing. Nondestmctive inspection of an explosion-welded composite is almost totally restricted to ultrasonic and visual inspection. Radiographic inspection is appHcable only to special types of composites consisting of two metals having a significant mismatch in density and a large wave pattern in the bond interface (see Nondestructive evaluation). 

J. Summerscales, ed.. Nondestructive Testing of Eibre-ReinforcedPlastic Composites, Vol. 1, Elsevier AppHed Science Pubhshers, Ltd., Barking, U.K., 1987, pp. 278, 627-629. 

A specific feature of the CEMS technique is the possibility for nondestructive testing of the surface composition of paintings, ancient coins, and pottery or other valuable objects. Wagner et al. [445] have investigated Celtic gold coins (from the time period 480-15 b.c.) and have shown that the surface of the coins consist of two phases, one of which is strongly eiuiched in gold compared to the bulk composition. 

The terms nondestructive testing and microanalysis refer to techniques for examining the internal structure and analyzing the composition of objects that, because of aesthetic or other considerations, cannot be studied by conventional techniques. 

Thermal imaging is sensitive to infrared radiation that detects temperature changes over the surface of a part when heat has been applied. Thermal diffusion in a solid is affected by variation in composition or by the presence of cracks, voids, delaminations, etc the effects are detected by surface temperature changes. Defects cannot be detected if their depth below the surface is more than two to three times their diameter. Nondestructive testing has been primarily used for composites and analysis of adhesive bonds or welds. Several studies are documented in the literature (322—327). 

The holographic systems based on dye sensitized polymerization suffer from the drawback that the presence of the dye interferes with effective image reconstruction. "Fixing" techniques have been devised (41), but they are only partly successful. Nevertheless, the Hughes compositions are used commercially for some nondestructive testing applications. 

Nondestructive testing and evaluation of composite hydrogen storage tanks... 

The manufacturer shall perform all fabrication and welding in accordance with an established written procedure. The first production pipe shall be sectioned and tested. Included in the testing shall be the normal physical property and nondestructive testing as well as a microhardness traverse across the weld and heat-affected zone (HAZ). The hardness shall not exceed 280 HV1Q at any location. Test results from previous production runs of these grades may be considered to fulfill this requirement if the chemical composition and wetding procedure used are substantially the same as proposed for this order. 

The Verein Deutscher Ingenieure (VDI) 2539 [15] relates to the surface protection coatings with organic materials. It deals exclusively with the testing of finished surface protective films made from organic materials and in this, only nondestructive testing procedures are described. The composition, properties and suitability of the protective material do not fall within these guidelines. 

NONDESTRUCTIVE TESTING OF DEFECT IN A C/SiC COMPOSITE Hui Mei, Xiaodong Deng, and Laifei Cheng... 

KEYWORDS Ceramic matrix composites Nondestructive testing Defects INTRODUCTION... 

Reynolds. W. N. (1986). Nondestructive testing techniques for metal-matrix composites. Harwell Report No. AERE-R-13040, UK. 

Zoughi. R.. and Ganchev. S. I. (1994), Application of microwave nondestructive testing and evaluation to thick composites. Proc. of the Conf on NDE Applied to Proce.ss Control of Composite Fabrication. Oct. 1994. pp. 77-89. 

Valleau. A. R. (1990), Eddy current nondestructive testing of graphite composite materials.. Materials Evaluation, Feb. 1990, 48. 2, 230-239. 

Handbook of Polymer Testing provides in one volume that comprehensive coverage of physical test methods for polymers. The properties considered cover the whole range of physical parameters, including mechanical, optical, electrical, and thermal as well as resistance to degradation, nondestructive testing, and tests for processability. All the main polymer classes are included rubbers, plastics, foams, textiles, coated fabrics, and composites. For each property, the fundamental principles and approaches arc discussed and particular requirements and the relevant international and national standards for the different polymer classes considered, together with the most-up-to-date techniques. 

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