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Results are given of theoretical and experimental investigations of schemes of matching of magnetocumulative generator (MCG)div class=”Abstract”. : Magnetocumulative Generators (Shock Wave and High Pressure Phenomena): Larry L. Altgilbers, Mark D.J. Brown, Igor Grishnaev, Bucur M. This paper presents the results of a computer simulation of coaxial magnetocumulative current generators (MCGs). The simulation tests were carried out for.

Such generators can, if necessary, be utilised independently, or even assembled in a chain of successive stages: By using this site, you agree to the Terms of Use and Privacy Policy. They are frequently used as the first stage of a multi-stage generator, with the exit current used to generate a very intense magnetic field in a second generator. The purpose of the flux generator can be either the generation of an extremely strong magnetic field pulse, or an extremely strong electric current pulse; in the latter case the closed conductor is attached to generattors external electric circuit.

By adding together the external magnetic field and the induced field, it can be shown that the net result is that the magnetic field lines originally threading the hole stay inside the hole, thus flux is conserved, and a current has been created in the conductive ring.

Retrieved from ” https: This page was last edited on 28 Novemberat The variation of the magnetic flux induces a current red arrows magnetocumultaive the ring by Faraday’s law of inductionwhich in turn creates a new magnetic field circling the wire green arrows by Ampere’s circuital law.

In the spring ofR. From Wikipedia, the free encyclopedia. The new magnetic field opposes the field outside the ring but adds to the field inside, so that the total flux in the interior of the ring is maintained: At the start of the s, the need for very short and powerful electrical pulses became evident to Soviet scientists conducting nuclear fusion research.

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Uspekhi Fizicheskikh Nauk in Russian. Explosively pumped flux compression generators are used to create ultrahigh magnetic fields in physics and materials science research [1] and extremely intense pulses of electric current for pulsed power applications.

An external magnetic field blue lines threads a closed ring made of a perfect conductor with zero resistance. Magneto-explosive generators use a technique called “magnetic flux compression”, described in detail below.

The nine field lines represent the magnetic flux threading the ring. An explosively pumped flux compression generator EPFCG is a device used to generate a high-power electromagnetic pulse by compressing magnetic flux using high explosive.

The compression process partially transforms the chemical energy of the explosives into the energy of an intense magnetic field surrounded by a correspondingly large electric current. The magnetic field lines are “pinched” closer together, so the average magnetic field intensity inside the ring increases magnteocumulative the ratio of the original area to the final area.

For this reason, reducing the area of the surface enclosed by a closed loop conductor with a magnetic field passing through it, which would reduce the magnetic flux, results in the induction of current in the electrical conductor, which tends to keep the enclosed flux at its original value.

Suppose the ring is deformed, reducing its cross-sectional magnetocimulative. Los Alamos Science Maxwell; Goforth, James; Ekdahl, Carl They are being investigated magneticumulative power sources for electronic warfare devices known as transient electromagnetic devices that generate an electromagnetic pulse without the costs, side effects, or enormous range of a nuclear electromagnetic pulse device.

Helical generators were principally conceived to deliver an intense current to a load situated at a magnetocimulative distance. The prohibitive cost of the capacitors required to obtain the desired power motivated the search for a more economical device.

The most intuitive explanation of this conservation of enclosed flux follows from Lenz’s lawwhich says that any change in the flux through an electric circuit will cause a current in the circuit which will oppose the change. In magneto-explosive generators, the reduction in area is accomplished by detonating explosives packed around a conductive tube or disk, so gemerators resulting implosion compresses the tube or disk.

Explosively-driven helical magneto-cumulative generators

Energy weapons Microwave technology Pulsed power Soviet inventions Russian inventions. This flux conservation can be demonstrated from Maxwell’s equations. International Journal of Quantum Chemistry. Views Read Edit View history. The technique is made possible when the time scales over which the device operates are sufficiently brief that resistive current loss is generaors, and the magnetic flux through any surface surrounded by a conductor copper wire, for example remains constant, even though the size and shape of the surface may change.

The Marx generatorwhich stores energy in capacitors, was the only device mavnetocumulative at the time of producing such high power pulses.

Buy ASTM D R GUIDE FOR PREPARATION OF METAL SURFACES FOR ADHESIVE BONDING from SAI Global. Purchase your copy of ASTM D – 01() as a PDF download or hard copy directly from the official BSI Shop. All BSI British Standards. Find the most up-to-date version of ASTM D at Engineering

Abrasive and debris should be wiped or water rinsed from the surface. Usually, the time should not exceed 8 h and parts should be covered or wrapped in Kraft paper. Trial bonding followed by testing and evaluation against mechanical strength standards should be conducted to determine initial and continuous effectiveness of a method.

Prepared surfaces can change their characteristics on standing and adhesives vary widely in their tolerance of adherend surface conditions. Apply the adhesive immediately after the treatment.

Search all products by. Records should indicate the continuous conditions of solutions, such as 2d651 of constituents added to bring solutions within limits, amount of contaminants present and date prepared see Methods D Adhesive bonds surface preparationCarbon steel, Copper, Copper alloy, Magnesium alloys, Metallic adhesives, Metal-to-metal contact, Stainless steel, Titanium alloys, Aluminum alloys-surface preparation for adhesive, bonding, Bond strength-adhesives metal-to-metalSurface preparation-adhesive bonding.

NOTE 1—No entirely foolproof method exists to determine bondability of a metal surface after preparation. Generally, not more than two repeat treatments are permitted. The d261 is anodically etched again using a wrapped electrode and a deep-etching solution.

Bond as soon as possible, but at least within the same working day. Click to learn aetm. Peening action of any blast process may work-harden the surface of some base metals.

Norma ASTM D()

Full-scale property tests should be run with the metal surfaces so prepared with the adhesive in question before accepting the process. Satisfactory surface preparations have been accomplished by using paste-type etchants.

Finishing voltages from 15 to 25 V are used. It produces a smut-free surface that can be treated by other chemical processes. Bond strengths obtained using either of these surface preparations are somewhat lower than those from the immersion processes.

The major problem is to apply sufficient thickness of coating to prevent corrosion, but not so thick that the bond fails within the coating. Rinsing may be done by spray or by dipping qstm a tank in which the water is circulated asmt constantly being renewed by an over?

This standard is subject to revision at any time by the responsible technical committee and must be reviewed every? This step is repeated if necessary until all visible contamination is removed. NOTE 9—If treating solution is to be used for a continuous operation or reused, it should be discarded after 4 to 6 h at the temperatures in This can be accomplished by wiping with a cloth wetted with a variety of commercial solvents, such as acetone, methyl ethyl ketone, lacquer thinner and naphtha.

Exercise care in using any mechanical method to prevent deep gouges or rough surfaces which are not conducive to good bonding.

ASTM D2651 – 01(2016)

This guide covers procedures for preparing various wrought metal surfaces for adhesive bonding. This guide covers procedures for preparing various wrought metal surfaces for adhesive bonding. Originally published as D asrm The adhesive or adhesive primer must be applied immediately after drying. Several commercial products qstm available. Hand sanding, rubbing with metal wool, and wire brushing are the least effective methods. It is not suitable for adhesives containing chlorides or for hot-bonding polyethylene.

After removing from any rinse the water-break test is commonly used.

If a water-break-free condition is not observed on the treated surface, it should not be used for bonding. Initial treatment is at about 5 to 10 V. You may experience issues viewing this site in Internet Explorer 9, 10 or The application of these paste systems allows for their use in fairly controlled areas. Accept and axtm Learn more about the cookies we use and how to change your settings. Sand blast, grit blast, or c2651 hone may be used. ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard.

Exercise r2651 care to ensure removal of all traces of the etchant. On the basis of the results of such an investigation, it may be possible to extend the length of time and establish standards for the interval between surface preparation and adhesive application aztm If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below.

Individual reprints single or multiple copies of this standard may be obtained by f2651 ASTM at the above address or at phonefaxor service astm. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend. Oxidation can occur in a very short time, even before the parts are dry.

ICS Number Code Wstm is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Surface preparation for magnesium alloys which is closely associated with corrosion prevention shall involve vapor, alkaline-detergent solution, chromic acid, and sodium hydroxide acid degreasing; anodic treatment; and the use of conversion coatings and wash primers.

Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard. Current edition approved Oct. A pH reading or acid content of trichloroethane vapor degreasing solution, or both, should be obtained.

The surface is the cathode. The surface will exhibit a grey or lighter color. Thin sheet steel may be warped due to peening of the blasting abrasives.