The Nb-Si based in-situ composite was produced by resistive sintering (RS) technique. In order to identify present phases, X-ray diffraction (XRD) analysis was used on the composite. XRD analysis revealed that the composite was composed of Nb solid solution (Nbss) and α-Nb5Si3 phases. The microstructure of the composite was characterized by using a scanning electron microscope (SEM). The energy-dispersive spectroscopy (EDS) was performed for the micro-analysis of the chemical species. SEM-EDS analyses show that the microstructure of composite consists of Nbss, Nb5Si3 and small volume fraction of Ti-rich Nbss phases. The micro hardness of constituent phases of the composite was found to be as 593±19 and 1408±33 Hv0.1, respectively and its relative density was % 98.54.
Contemporary materials engineering requires the use of materials characterised by high mechanical properties, as these precisely
properties determine the choice of material for parts of machinery and equipment. Owing to these properties it is possible to reduce
the weight and, consequently, the consumption of both material and energy. Trying to meet these expectations, the designers are
increasingly looking for solutions in the application of magnesium alloys as materials offering a very beneficial strength-to-weight ratio.
However, besides alloying elements, the properties are to a great extent shaped by the solidification conditions and related structure.
The process of structure formation depends on the choice of casting method forced by the specific properties of casting or by the specific
intended use of final product. The article presents a comparison of AZ91 magnesium alloys processed by different casting technologies.
A short characteristic was offered for materials processed by the traditional semi-continuous casting process, which uses the solidification
rates comprised in a range of 5 - 20⁰C/s, and for materials made in the process of Rapid Solidification, where the solidification rate can
reach 106 ⁰C/s. As a result of the casting process, a feedstock in the form of billets and thin strips was obtained and was subjected next
to the process of plastic forming. The article presents the results of structural analysis of the final product. The mechanical properties
of the ø7 mm extruded rods were also evaluated and compared.
The application of the 5S methodology to warehouse management represents an important
step for all manufacturing companies, especially for managing products that consist of
a large number of components. Moreover, from a lean production point of view, inventory
management requires a reduction in inventory wastes in terms of costs, quantities and time
of non-added value tasks. Moving towards an Industry 4.0 environment, a deeper understanding
of data provided by production processes and supply chain operations is needed:
the application of Data Mining techniques can provide valuable support in such an objective.
In this context, a procedure aiming at reducing the number and the duration of picking
processes in an Automated Storage and Retrieval System. Association Rule Mining is applied
for reducing time wasted during the storage and retrieval activities of components
and finished products, pursuing the space and material management philosophy expressed
by the 5S methodology. The first step of the proposed procedure requires the evaluation
of the picking frequency for each component. Historical data are analyzed to extract the
association rules describing the sets of components frequently belonging to the same order.
Then, the allocation of items in the Automated Storage and Retrieval System is performed
considering (a) the association degree, i.e., the confidence of the rule, between the components
under analysis and (b) the spatial availability. The main contribution of this work is
the development of a versatile procedure for eliminating time waste in the picking processes
from an AS/RS. A real-life example of a manufacturing company is also presented to explain
the proposed procedure, as well as further research development worthy of investigation.