yazik.info Physics Astm D1621 Ebook

ASTM D1621 EBOOK

Sunday, October 6, 2019


D Standard Test Method for Compressive Properties of Rigid Cellular Plastics rigid Standard + Redline PDF Bundle ASTM License Agreement. D - 00 Standard Test Method for Compressive Properties Of Rigid Cellular Plastics, cellular plast Format, Pages, Price. PDF ASTM License Agreement. This standard is issued under the fixed designation D ; the number 1 This test method is under the jurisdiction of ASTM Committee D on Plastics.


Astm D1621 Ebook

Author:CHANTE TETEAK
Language:English, Spanish, French
Country:Niger
Genre:Art
Pages:300
Published (Last):20.09.2015
ISBN:855-6-70420-527-9
ePub File Size:22.64 MB
PDF File Size:10.56 MB
Distribution:Free* [*Register to download]
Downloads:48202
Uploaded by: DWANA

ASTM D—10 Standard Test Method for Compressive Properties of This convenient option is a searchable PDF download that requires a PDF Reader. Oct 26, ASTM D - Designation: D – 10 Standard Test Method for Compressive Properties of Ri. ASTM D specifies the test conditions for determining the compressive properties of rigid cellular materials, particularly expanded plastics. Rigid foams.

AE is an active NDT method and can be utilized for condition monitoring of composite parts and production control, as well as assessing severity of flaws and damages. It has been used extensively in composites not only to identify various failure modes, to define defects and to locate AE souces, but also to conduct real time monitoring during proof testing and in service.

Each failure mode, namely, fibre breaking, matrix cracking, interfacial debond or delamination is found to exhibit distinct characteristic AE signals. But the identification of individual modes becomes extremely difficult when two or more failure modes occur simultaneously.

The types of fibres and matrices, the anisotropy, the stacking sequence, structural boundaries, presence of micro-defects, etc.

All these problems need to be solved before AE can be routinely used as an NDT tool in development of composite materials and structures. In holography, the entire optical wavefront both with respect to amplitude and phase is recorded in a film and phase is recorded in a film is called 'hologram' after the Greek word holos meaning 'whole'.

A hologram preserves the three-dimensional character of an object for which the hologram has been made.

Quick Links

A simple holographic set-up Fig. One wavefront i. The other wavefront, i. The two wavefronts create a complex interference pattern which is recorded on the holographic film. The interference lines represent points with the same displacement. The coherence of the laser light permits the interference of these two waves, although there exist relatively large differences in path length.

The recorded holographic film, or the hologram when illuminated with the reference wave, the object wave is reconstructed and a three-dimensional view of the object can be observed behind the hologram Fig.

Several images which interfere with each other can be stored on the same film, which can be reconstructed when required. The popular double exposure method, in which holograms of an object in two different states, e.

The double exposure method is also known as frozen fringe HI. There are other HI methods which are used for specific purposes. The 'simulataneous method' or real time HI first creates a hologram of the object in a desired reference state, which is later used as a reference hologram with respect to which subsequent changes in the object position are recorded by filming the hologram image.

The 'time averaging method' is used to record small amplitude oscillations of vibratory parts. The hologram of a vibrating body is first recorded on a film for a time interval longer than the period of oscillation and in the process a set of holograms are superimposed.

Other books: FASS MICH AN EBOOK

The resulting hologram when reconstructed, reveals nodal lines as dark interference stripes. HI has a great potential for NDT applications. The capability of HI is enhanced considerably after the introduction of video and popular with the NDT personnel working in the field of composites and composite structures.

The real time monitoring of a component using HI, especially during the service life, still poses a problem as it is not easy to isolate vibration in the production and in-service environment.

Deflection, Crushing of Roof Insulation Can Contribute to Single-Ply Roofing Failures

The vibrational displacement of the object as small as one-quarter wavelength of the laser light may produce fringes on the hologram.

The use of phase-locked holography may alleviate problems associated the low frequency environmental vibration.

The phase-locked holography uses the diffuse reflection of an unexpanded beam shone on a small portion of the test object as the reference beam. Another important development in this area is the electronic shearogrphy in which no separate reference beam is used.

In this case, the returning object beam is doubly imaged with a video system.

One image is then found to be slightly shifted or sheared relative to the original one. This shearing fringe pattern can be isolated from the real fringes. X-rays are independent of the magnetic and electrical properties of a material and hence can be used with all materials.

Two major characteristics of X-ray radiographic NDT method are that X-rays are absorbed differentially by different media and they produce photochemical effects in photographic emulsions.

Thus it is observed from Eq 5. The attenuation depends on the absorption coefficient and the thickness of the material. So the intensities of the X-ray beams passing through the material thickness with and without a void will be different.

When these transmitted beams are allowed to strike a photographic film, they create a contrast on the exposed film or radiograph i. It is also possible to determine the thickness and composition of a material by examining differences in the exposed film. Normally voids of small sizes closer to fibre dimensions , and cracks and delaminations that exist normal to the X-ray beam are not easily detectable.

However, inclusions, cracks, delaminations and other material defects and damages that are aligned parallel to the X-ray beam can be readily revealed.

ASTM D – Compression Testing of Rigid Cellular Plastics

The X-ray radiography has also been applied to investigate the microstructural details of damages using low energy X-rays as well as using an X-ray opaque penetrant e. The penetrant, however, should not react chemically with the constituents of the composite medium.

Roofing manufacturers don't typically require cover boards, and so they're often eliminated from the roofing system to reduce costs.

Cover boards should always be considered in roofing systems, specifically for protection of the insulation and for the benefits of prolonging the roof membrane itself.

The test defines failure as the point of plastic deformation — i.

Deflection that is less than 10 percent of the insulation thickness can be sufficient to damage the roofing membrane. For example, 9 percent deflection of six inches of insulation is more than half an inch.

Regular foot traffic, tool carts, equipment, and concentrated loads can cause the insulation to deflect or exceed the compressive strength of the insulation boards, and crush the foam insulation core or separate the facer from the insulating core.

Hail can also cause widespread damage to the insulation beneath the roofing membrane.

ASTM D

Deflected or crushed insulation, or separation of the facer from the insulation core, causes the membrane to fail and become unsupported, which decreases the puncture resistance of the membrane and can cause seams to open. The accuracy of the displacement measurement transducer shall be veri? This variance is a function of load frame stiffness, drive system wind-up, load cell compliance and?

This compliance can be measured then, if determined to be signi? The procedure to determine compliance follows: 1 Con? Stop the crosshead and return to the pre-test location. On each specimen test curve at each given load value, subtract the system compliance from each recorded displacement value.

More Than Insulation. We Offer Solutions

This will be the new load-de? Test Specimen 6. The minimum height shall be Care should be taken so that the loaded ends of the specimen are parallel to each other and perpendicular to the sides.

NOTE 2—Cellular plastics are not ideal materials, and the compressive modulus may appear signi? All data that are to be compared should be obtained using common test conditions.

Conditioning 7. Procedure 8.

Hold the pressure of the dial foot to 0. When a slidingcaliper gage is employed, the proper setting shall be that point at which the measuring faces of the gage contact the surfaces of the specimen without compressing them.

It will expedite the testing process if, when the specimen is in place, the upper platen is positioned close to, but not touching, the specimen. This recorded curve will be used directly if following 5. Substitute the speci? Calculation 9. Specimens that fail at some obvious? Measure all distances for deformation or strain calculations from this point.Even the existence of a piece of paper or a similar material contained within a laminate can be easily identified from the reflected signal strength.

Patel and Matthew J. By mapping the surface and using angle probes the size and orientation of a crack can also be determined. A continuous ultrasonic wave is transmitted through the material, and the mechanical stiffness or impedance of the material is monitored.

Published April Specimens that fail at some obvious?