SU1478102A1

SU1478102A1 - Method for determining material friction coefficient in plastic deforming drawing

Info

Publication number: SU1478102A1
Application number: SU874240175A
Authority: SU
Inventors: Олег Александрович Розенберг; Анатолий Дмитриевич Крицкий; Сергей Александрович Родюков; Сергей Евгеньевич Шейкин
Original assignee: Институт сверхтвердых материалов АН УССР
Priority date: 1987-05-05
Filing date: 1987-05-05
Publication date: 1989-05-07

Abstract

Изобретение относитс к области испытани материалов и может быть использовано дл определени коэффициента трени при пластически деформирующем прот гивании. Целью изобретени вл етс снижение трудоемкости определени коэффициента трени путем исключени измерени крут щего момента при поступательно-вращательном перемещении образца. Образец 1 ввод т в соприкосновение с контробразцом 2, нагружают осевым усилием, измер емым динамометром 3, с одновременным вращением вокруг оси. При достижении образцом 1 середины контробразца 2 прекращают вращение образца 1, совершают только поступательное перемещение с измерением осевого усили и определ ют коэффициент трени . 1 ил.The invention relates to the field of testing materials and can be used to determine the coefficient of friction during plastically deforming. The aim of the invention is to reduce the laboriousness of determining the coefficient of friction by eliminating the measurement of torque during translational-rotational movement of the sample. Sample 1 is brought into contact with counterpiece 2, loaded with axial force measured by dynamometer 3, with simultaneous rotation around the axis. When the sample 1 reaches the middle of the contra-sample 2, the sample 1 rotation is stopped, only translational movement is made with the axial force measurement, and the coefficient of friction is determined. 1 il.

Description

11А 11A

Изобретение относитс к области испытани материалов, в частности к способам определени коэффициента трени при пластически деформирую- щем прот гивании.The invention relates to the field of testing materials, in particular, to methods for determining the coefficient of friction during plastically deforming pulling.

Целью изобретени вл етс снижение трудоемкости процесса определени коэффициента трени путем исключени операции измерени крут щего момента при поступательно-вращательном перемещении образца в контробразце .The aim of the invention is to reduce the laboriousness of the process of determining the coefficient of friction by eliminating the torque measurement operation during the translational-rotational movement of the sample in the counter sample.

При этом отпадает необходимость динамометра дл измерени крут щего момента, а измер етс только осева сила, действующа на образец.There is no need for a dynamometer to measure the torque, and only the axial force acting on the sample is measured.

На чертеже изображена схема устройства дл реализации способа.The drawing shows a diagram of the device for implementing the method.

g - угол наклона винтовой линии к оси, который определ етс отношением скорости вращательного движени V 8 к скорости поступательного движени Vn образца, т.е.g is the angle of inclination of the helix to the axis, which is determined by the ratio of the speed of rotational movement V 8 to the speed of translational movement Vn of the sample, i.e.

Claims

Vb j-arctg .VH claims

A method for determining the friction coefficient of a material during plastically deforming pulling, which consists in the fact that a sample of material with a working surface in the form of a truncated cone leads simultaneously

The device contains sample 1, 20 but rotationally around the axis of the cone

filled with a truncated cone working surface, counterpiece 2 with an internal cylindrical working surface. Counterpiece 2 is mounted on the upper end of the dynamometer 3 to measure the axial force, and key 4 prevents the counter-rotation in the first stage.

The method is implemented as follows.

Sample 1 is brought into contact with counterpiece 2 mounted on the upper end of the dynamometer 3. Spiraling sample 2 is held by key 4. An axial load is applied to sample 1 and its translational rotational movement is carried out, plastically deforming the counterpiece 2 and fixing the axial force P / When the end face of sample 1 reaches the middle of the length of counterpiece 2, the rotational movement stops and only translational movement of sample 1 is carried out, and the axial force Pg is fixed.

The coefficient of friction is determined by the formula

f

P ; P 1 - PICOSt

where P1 is the axial force during the translational-rotational movement of sample 1;

Ps. - axial force in the progressive movement of sample 1; f is half the angle of the working cone of sample 1;

-tg (s

and translational along the axis of the cone of movement relative to the counterpiece with the inner cylindrical working surface, measure the axial force of pulling and the angle of inclination of the helix and determine the coefficient of friction, which differs so that, in order to increase accuracy and reduce labor intensity

determining the friction coefficient, simultaneous rotational and translational movements of a sample of a material are carried out until the end of the sample reaches the midpoint of the

surface of the counter piece, and then carry out only a translational movement, the axial force of pulling is measured at this movement,

and a factor of 40 by the formula

f friction is determined

Pr - P,

PjCOS f

tg / i

P f

where P is the axial force when entering. rotary motion of the sample;

P is the axial force during the translational movement of the sample;

p is half the angle of the working cone of the sample;

t- is the angle of inclination of the screw trajectory of the sample movement to its axis. .