SU1385037A1 - Method of testing strength of adhesive bond for shear - Google Patents

Abstract

The invention relates to a test technique, is intended to determine the strength of the adhesive bond to a section of contacting pairs under load and allows the test conditions to be closer to the conditions of operation of the elements of the power electrical contacts. In the test chamber 1, parallel plates 2, 3 are placed, separated by a spherical indenter 4. Blocks 5.6 and 7 support the specified test conditions in chamber 1. The plates 2, 3 are brought into contact with the spherical indenter 4 and are loaded with a force P up to 25 kN while simultaneously passing an electric current through the plates 2, 3 of 15 to 500 A. After holding the plates 2, 3 under load, disconnect the electric current and carry out turning the spherical indenter 4 around the axis through an angle of up to 360. At the same time, the torque is measured. The magnitude of the electric current is chosen from the conditions for ensuring the softening of the material of the plates 2, 3. 1 sludge. with

Description

h

F

The invention relates to a test technique, and specifically to methods for determining the strength of adhesive bonding in a section of contacting pairs under load.

The aim of the invention is to approximate the test conditions to the operating conditions of the elements of the power electrical contacts.

The drawing shows a diagram of an apparatus for implementing a method for determining the strength of adhesive bonding on a shear.

The device for determining the strength of the adhesive bond to the shear contains a test chamber 1 with parallel plates 2 and 3, a separated spherical indenter 4, blocks 5, 6 and 7, supporting test conditions set in the chamber, instrumentation 8 and electrical busbars 9, connected to a transformer (not shown).

plates 2, 3. In the case of an electric current of more than 500 A, re-cracking (decomposition) of the oil microvolumes occurs, resulting in welding of the indenter 4 to the plates 2, 3,

After holding the samples under load, the electric current is disconnected and

10, the spherical indenter is rotated around an axis at an angle of up to 360 with a constant rotational speed and simultaneous measurement of the torque using a coitro-measuring equipment. Upon completion of the test, the load is removed from the samples, the plates are retracted. And replaced with a new pair made of other materials

20 after which the test cycle is repeated

I

The use of the method of determining the strength of adhesion bond on the cut compared with the known technical methods. The method of determining the strength of adhesion solutions provides expansion

plates 2, 3. In the case of an electric current of more than 500 A, the microvolumes of the oil are re-cracked (decomposed), leading to the welding of the indenter 4 to the plates 2, 3,

After holding the samples under load, disconnect the electric current and

the spherical indenter is rotated around the axis through an angle of up to 360 with a constant rotational speed and simultaneous measurement of the torque using coitro instrumentation equipment. Upon completion of the test, the load is removed from the samples, the plates are retracted. And replaced with a new pair made of other materials

after which the test cycle is repeated,

I

Using the method of determining the strength of adhesive bond on the cut compared with the known technical

zionic communication for shear is degraded as follows.

Plates 2 and 3 are installed in the chamber in the sample holder, then brought into contact with the spherical indenter 4 and loaded with a force P up to 25 kN with simultaneous passing of electric current through the samples from 15 to 500 A,

Loaded specimens are kept under load from 0.25 to 25 kN, from

at the same time spherical inv

0.1 to 1 h,

Dentor pressed simultaneously

top and bottom plates,

To eliminate the influence of the accuracy of the temperature test results, as well as to bring the test conditions of the samples closer to the actual operating conditions of the contacts in the power electric switches and switches, oil is pumped through the cavity of the test chamber 1.

In the case of an electric current passing through the samples less than 15 A, no softening of the material is observed between the indenter and the plates.

functionality by providing the ability to test and select the optimal combination of materials of contact pairs of power contacts of electrical switches and switches.

Claims (1)

Invention Formula A method for determining the strength of adhesion bond to a shear, in which samples made in the form of two parallel plates and a spherical indenter installed between them are rotated relative to each other in a plane, the perpendicular line of action of the compressive load at the moment of the last action, and the value of court loads T is about the strength of the adhesive bond, characterized in that, in order to bring the test conditions to the operating conditions of the elements of the power electrical contacts, when subjected to a compressive load through the samples pass an electric current, the value of which is chosen from the condition 15A 1 500 A,