Refinement is one of the most energy consuming technological process, aimed at obtaining mineral raw materials of the proper grain size.
Cast structural elements such as jaws or hammers in crushing machines operate under conditions of an intensive wear. The data indicate
that 80 % of failures of machines and devices is caused by wearing of rubbing surfaces. This problem became the subject of several
scientific and industrial investigations carried out in the whole world in order to produce materials ultra- wear resistant. Methods allowing
to obtain wear resistant composite castings are discussed in the hereby paper. Within the performed research microstructures of the
produced composite zones were presented and the comparative analysis with regard to mechanical and functional properties of local
composite reinforcements in relation to the commercial alloys of increased wear resistance was performed. The results show almost twenty
five times increase in wear resistance compared to manganese cast steel containing 18 % Mn.
Wear resistance of TiC-cast steel metal matrix composite has been investigated. Composites were obtained with SHSB method known as
SHS synthesis during casting. It has been shown the differences in wear between composite and base cast steel. The Miller slurry
machine test were used to determine wear loss of the specimens. The slurry was composed of SiC and water. The worn surface of
specimens after test, were studied by SEM. Experimental observation has shown that surface of composite zone is not homogenous and
consist the matrix lakes. Microscopic observations revealed the long grooves with SiC particles indented in the base alloy area, and
spalling pits in the composite area. Due to the presence of TiC carbides on composite layer, specimens with TiC reinforced cast steel
exhibited higher abrasion resistance. The wear of TiC reinforced cast steel mechanism was initially by wearing of soft matrix and in
second stage by polishing and spalling of TiC. Summary weight loss after 16hr test was 0,14÷0,23 g for composite specimens and 0,90 g
for base steel
The work presents the investigation results concerning the structure of composite pressure die castings with AlSi11 alloy matrix reinforced
with SiC particles. Examination has been held for composites containing 10 and 20 volume percent of SiC particles. The arrangement of
the reinforcing particles within the matrix has been qualitatively assessed in specimens cut out of the castings. The index of distribution
was determined on the basis of particle count in elementary measuring fields. The tensile strength, the yield point and elongation of the
obtained composite were measured. Composite castings were produced at various values of the piston velocity in the second stage of
injection, diverse intensification pressure values, and various injection gate width values. The regression equation describing the change of
the considered arrangement particles index and mechanical properties were found as a function of the pressure die casting parameters. The
infuence of particle arrangement in composite matrix on mechanical properties these material was examined and the functions of
correlations between values were obtained. The conclusion gives the analysis and the interpretation of the obtained results.
In order to increase wear resistance cast steel casting the TiC-Fe-Cr type composite zones were fabricated. These zones were obtained by
means of in situ synthesis of substrates of the reaction TiC with a moderator of a chemical composition of white cast iron with nickel of
the Ni-Hard type 4. The synthesis was carried out directly in the mould cavity. The moderator was applied to control the reactive
infiltration occurring during the TiC synthesis. The microstructure of composite zones was investigated by electron scanning microscopy,
using the backscattered electron mode. The structure of composite zones was verified by the X-ray diffraction method. The hardness of
composite zones, cast steel base alloy and the reference samples such as white chromium cast iron with 14 % Cr and 20 % Cr, manganese
cast steel 18 % Mn was measured by Vickers test. The wear resistance of the composite zone and the reference samples examined by ballon-disc
wear test. Dimensionally stable composite zones were obtained containing submicron sizes TiC particles uniformly distributed in
the matrix. The macro and microstructure of the composite zone ensured three times hardness increase in comparison to the cast steel base
alloy and one and a half times increase in comparison to the white chromium cast iron 20 % Cr. Finally ball-on-disc wear rate of the
composite zone was five times lower than chromium white cast iron containing 20 % Cr.
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