SU1401359A1 - Device for determining friction coefficient in plastic deformation - Google Patents

Abstract

This invention relates to a measurement technique for studying friction processes. The aim of the invention is to increase the performance of the coefficient of friction determination. Two identical indenters 4 are pressed into the sample 11 when they are loaded through the rods 2 and 3 and the equal arm rocker, 5. With an uneven strain rate of the sample material in the contacts, indicator 9 registers this difference. The loading is stopped. The diameter of the smallest well on sample 11 is measured and the coefficient of friction is determined. 1 Il.

Description

(L

114

The invention relates to the field of mechanical engineering and can be used to study the tribological properties of materials during their plastic deformation.

The aim of the invention is to improve the performance of determining the coefficient of friction by comparing the depth of insertion of two ball indenters installed at the ends of parallel rods, with plastic contact with the test sample.

The drawing shows the proposed device.

The device includes a housing 1, rods 2 and 3 with a ball indenter 4 attached to the ends of the rods, a loading mechanism (not shown), an equal-shoulder rocker 5, guides 6 and 7 with screw 8, an indicator 9 and a sample holder 10 I.

The device works as follows.

Sample 11 is fixed on the holder 10 and, at the points of contact of the indenters 4 on sample 11, unequal friction conditions are created (two different lubricants are applied, different roughnesses are provided, etc.). With the help of the loading mechanism, the normal load P is applied. At the same time, the yoke has 5 salons, and the loading mechanism, kinematically connected with the rods, is different. In order to increase productivity, it is equipped with an equal-arm rocker installed in a building and connected with a loading mechanism, whose shoulders are supported On the free ends of the rods, two parallel guides fixed by each arm t of length A / 2 transfers this to a 35 ° stem and located

ra 9 will move from zero position. At this point, the loading is stopped, the diameter d of the smallest well on sample 11 is measured and the coefficient of friction is determined by the formula

f d where O is the diameter of the spherical indenter.

The proposed device improves the performance of the test due to the fact that sample 11 can be used many times, and the contact conditions can also be quickly changed using different lubricants.

Claims (1)

Invention Formula A device for determining the coefficient of friction during plastic deformation, comprising a housing, two rods located in the housing with the possibility of their axial movement, indenters fixed at the ends of and the loading mechanism, kinematically associated with the rods, is different. in order to increase productivity, it is equipped with an equal-arm rocker mounted in the housing and connected to the loading mechanism, whose shoulders are supported On the free ends of the rods, two parallel guides fixed each on the corresponding stem and located load in the same way through rods 2 and 3 and indenters 4 onto sample 11. Indenters 4 begin to penetrate into the sample material. Under different conditions of contact, the friction coefficients in the two pairs of indenter-sample are different. Therefore, one of the indenters is inserted into the sample faster, and the other is slower, and the indicator is perpendicular to their axis, with an indicator fixed on one of the guides with the possibility of their measuring tip interacting with another guide and a sample holder mounted on the body and opposite the indenters, which are made in the form of balls of equal diameter.