CERAMIC PARTICLES FOR THE MAGNETO-ABRASIVE TREATMENT
OF METALLIC SURFACES
T. V. Mosina,
K. A. Gogaev,
V. V. Nepomnyashchii,
S. M. Voloshchenko,
V. A. Nazarenko,
and M. G. Askerov
Translated from Novye Ogneupory, No. 9, pp. 43 – 45, September, 2011.
Original article submitted May 16, 2011.
It is shown that a uniform distribution of the abrasive component in the matrix of the granules of mag
neto-abrasive materials (MAMs) gives these materials good cutting and polishing ability. The durability of
MAMs in which the abrasive component is secured in the matrix by friction, adhesives, and surfactants is de
termined by the rate of wear and the adhesive interaction between the initial components. The adhesive-, fric
tion-, and surfactant-bonded magneto-abrasive powders proposed in this article can compete with the mag
neto-abrasive powders made by established methods.
Keywords: ceramic powders, magneto-abrasive materials (MAMs), magneto-abrasive treatment (MAT),
roughness, demagnetizing factor, cutting ability.
The factors that determine the quality of surfaces pol-
ished by magneto-abrasive treatment (MAT) are the geomet-
ric form of the particles that are used and the optimality of
the structure of the granules that comprise magneto-abrasive
materials (MAMs). The structure of composite MAMs hav-
ing a ferromagnetic matrix and including an abrasive compo-
nent is optimized on the basis of the following principles.
1. Determination of the optimum content of the abrasive
component and the character of its distribution in the ferro
2. Determination of the dispersity and geometric param
eters of the MAM granules.
3. Determination of the dispersity and physico-mechani
cal characteristics of the particles of the abrasive material.
In the study being discussed here, we examined the sin
gle-factor dependences of the service properties of compos
ite MAMs on the structure of their granules. We proceeded
on the basis of the fact that the maximum attainable rough
ness in MAT depends on the parameters of the particles that
make up the abrasive material. The properties of the granules
of composite MAMs can affect the degree of roughness that
is attainable because they determine cutting ability in the
treatment and the corresponding rate of removal of traces of
material from the previous treatment. An increase in the con
tent of the abrasive component improves cutting ability by
increasing the number of cutting centers per unit of the sur-
face being treated. The upper limit for the content of the
abrasive component is constrained by the fact that the mag-
netic properties of the ensemble of magneto-abrasive gran-
ules deteriorate to the critical values that determine whether
or not they remain inside the working gap of the machine
used to perform the treatment. For example, for selected test
conditions in a machine used to treat cylindrical surfaces
with the induction of a 1-T field, the powder of the MAM is
reliably held in the 0.7-mm gap when its iron content is on
the order of 30 vol.%. This result is consistent with the con
clusions reached in . A decrease in the size of the particles
of the abrasive material decreases their limiting concentra
tion because it increases the demagnetizing factor associated
with the granules of the MAM due to an increase in the con
centration of pores. In this instance, the particles can be re
garded as pores. The demagnetizing factor is also affected by
the distribution of abrasive material in the matrix of the gran
ules. The structure is formed when the abrasive material is
located on the surface of the particle.
Analyzing the structure of magneto-abrasive granules, it
can be concluded that the abrasive particles located inside
granules do not take part in the cutting operation. They only
increase the demagnetizing factor, thus decreasing magnetic
permeability. Composite abrasive materials formed with the
use of a surfactant and adhesives are similar in structure to
the granules just mentioned. Tests of such MAMs have
shown that their structure gives the MAM high durability
Refractories and Industrial Ceramics Vol. 52, No. 5, January, 2012
1083-4877/12/05205-0355 © 2012 Springer Science+Business Media, Inc.
Institute of the Problems of Materials Science, National Academy
of Sciences of the Ukraine.