SU1668865A1 - Method of measuring metal surface roughness - Google Patents

Abstract

The invention relates to a measurement technique and can be used, in particular, to detect sharp chips on rough metal surfaces. The purpose of the invention is to expand the information content of the method by detecting sharp chips on a metal surface. Directional flow first floor rizuyut in a vertical plane and measured intensity I ⁱⁿ reflected backwards vertically polarized light is then directed flow field rizuyut horizontally and measured intensity I ^r of the reflected backwards horizontally polarized light and the relative intensities I ^g / I ^is judged on the presence of chips, and the cleavage angle α is determined from the ratios D [I ^g / I ^c = (SIN (ψ / N) SIN (ψ ₀ / N) / COS (ϕ / N) - COS (ψ / N) COS (ψ ₀ / N) ²

Α = 2ϕ - Nϕ, where ψ ₀ and ψ are the angles between the edges of the cleavage and the incident and reflected rays, respectively. 1 il.

Description

The invention relates to a measurement technique and can be used, in particular, to detect sharp chips on rough metal surfaces (a sharp chip means a peak of an irregularity with a radius of curvature much smaller than the average radius of curvature of the vertices of all the irregularities).

The aim of the invention is to expand the information content of the method by detecting the presence or absence of sharp chips on irregularities and making it possible to measure the chip angles.

The drawing shows a schematic diagram of a device implementing the method.

The device contains a source of monochromatic light, a polarizer 2, an analyzer 3 and a receiver 4 of the scattered light flux.

The method is carried out as follows.

From the source 1 of monochromatic light with wavelength A, the light flux 6 is directed through the polarizer 2 normally to the test surface 5. The intensity of the reflected light flux 7 passing through the analyzer 3 is recorded by the receiver 4. The directed light flux is first polarized in a vertical plane and measure the intensity I reflected in reverse

00 00

about ate

the direction of the vertically polarized light, then the directional flow is polarized horizontally and the intensity is measured

Irr of the backward reflected horizontally polarized light and

| R

the ratio of intensities - the judgment

the presence of the chips, and the value of the angle a of the chip is found from the ratio

jfr

ig.

sin $ sin (%

COS $ -COS $ COS (&)

a 1 ptg

where Vb and V Angles between the edges of the cleavage and the incident and reflected rays, respectively.

Claims (1)

The invention of the method of determining the roughness of a metal surface, consisting in that a monochromatic light flux of known intensity is directed onto a controlled surface 0 five 0 five the intensity of the reflected luminous flux is recorded and the surface roughness, characterized in that, in order to expand the informativeness of the method by detecting sharp chipping on a metal surface, the directional luminous flux is polarized in a vertical plane and the intensity of the reflected in the opposite direction is measured vertically led light then the directional light flux is polarized in a horizontal plane and the intensity Irr of the horizontally polarized light reflected in the opposite direction is measured and the presence or absence of chips is judged by the intensity ratio, and the angles $ and f) between the faces of the chips and the incident and the reflected rays, respectively, and the cleavage angle a is determined from the ratio a - 2 L gig, where n is calculated from the ratio | G / 1 l / 1 / "Choip / ./, 2 IBB 51p (/ p) sn (y0 / p) COS (7T / n) - COS (l / / n) COS (Vfe / n)