Abstract: The powder metallurgy technique was adopted to prepare SiCp copper alloy matrix
composites. The mechanical properties of the composites were measured to investigate the
influence of processing parameters, SiC particle characteristics and metallic coating (copper) of the
SiC particles. It was found that the mechanical properties of the composites prepared by pressing,
sintering, re-pressing, and resintering are superior to those of composites prepared by the pressing
and sintering route, and that sintering temperature was an important factor in controlling composite
properties. Changes in hardness, theoretical density, ultimate tensile strength, and wear resistance of
composites containing SiC of varying silicon carbide content were observed. In all cases,
composites made from copper coated SiCp exhibited better properties than those from uncoated
Abstract: The paper presents studies about reducing the sintering temperature of PM High-Speed
Steel obtained by water atomization. The powder was characterized to proceed with compaction and
sintering at different temperatures between 1140-1220°C in different atmospheres: nitrogen (N2),
nitrogen-hydrogen-methane (N2/H2/CH4) and vacuum. It is described the experiment in able to
increase hardness by a quenching and tempering heat treatment that was carried out on sintered
samples at 1140°C in vacuum atmosphere at 1200°C in N2/H2/CH4.
Abstract: The present paper presents experimental results on Al foam produced by powder
metallurgy method. Their lightweight property makes them attractive for the cores of structural
sandwich panel in products ranging from sport equipment to lightweight building panels. The
process of metallic foam manufacture as well as the testing methods used for the characterization of
their physical, mechanical and chemical properties will be exposed.
Abstract: An original inverse extrusion test was developed in order to study the microstructural
evolution in the plastic deformation of 6060 and 6082 aluminium alloys. Sample billets were
extracted from commercial logs and subjected to plastic deformation in an inverse extrusion
process, particularly aimed at producing different strain and strain rate conditions at representative
positions within the billet section. Different experiments were performed at various temperatures
and strain rates. The particular thermo-mechanical history of each point in different experiments
was then reconstructed by FEM analysis. The cups were sectioned and the microstructure was
analysed at some representative locations, to relate it to the FEM simulation results.
Abstract: The paper presents some experimental data about the thixoforming process applied to
different aluminum alloys very used in the Romanian machine building industry.
From many procedures for obtaining the semisolid slurry described in the paper, based on
specialized literature [2, 3, 4] in particular, the accent is given to choose the mechanical mixture in
the overheated mould until it reached the liquid alloy temperature. The main results are based on
reducing of stirring time for increasing the benefits of the new technology.
All procedures and results are described in the paper and also some specific conclusions are given.
The experimental data of the research, were obtained in the specific testing laboratory from
Transilvania University of Brasov.
Abstract: In metal forming processes in the tool-workpiece contact area occur high pressure,
surface expansion and elevated temperature. It makes ideal circumstances for braking of the
lubricant film that causes a direct contact between metallic surfaces. Such a contact usually leads to
buildups creation on the tool surface. These phenomena mainly result product surface damage.
Damages can also refer to tool surface since the hardness of buildups can be comparable with the
tool hardness. The cause of this investigation was finding the answer of the question what was the
reason of extreme hardness of buildups created during bulk metal forming processes of 1H18N9T
austenitic stainless steel. The studies were conducted using transmission electron microscopy
(TEM). On the basis of analysis structural and electron diffraction pattern it was suggested that
simultaneously to very well known strengthening mechanism like grain refinement, the additional
mechanism can not be excluded. Based mostly on the electron diffraction pattern (appearance of
forbidden reflexes for FCC) it is suggested that this additional mechanism could be the marthensitic
transformation caused by very high plastic deformation.
Abstract: 3D Scanners are used in industrial applications such as reverse engineering and
inspection. Customization of existing CAD systems is one of rapid ways to supplying a 3D
Scanning software. In this paper, using AutoLisp and Visual Basic programming languages,
AutoCAD has been customized. Also facilities of automatic scanning of physical parts, in the
domain of free form surfaces, have been provided. Furthermore, possibilities such as, control of
scanner automotive system, representation of registered point clouds, generation of polygon and /or
NURBS model from primary or modified point clouds, have been prepared. Triangulation and
image processing techniques along with a new fuzzy logic algorithm have been used to extract the
depth information more accurate. These, accompanying with AutoCAD capabilities have provided
acceptable facilities for 3D scanning.
Abstract: The most important activity of wire drawing technology is the correct design of stages
geometry. The wire drawing within a roller die is described by an irregular deformation on wire
width, strongly connected by the gauge shape between the rollers and cross section wire surface.
Free lateral wire surface that has no contact with the roller on the deformation zone obstructs the
wire elongation. There is a biunique correspondence between the shape and dimension of wire that
enters between the rollers, and the free space between the rollers, corresponding to a specific stage
of drawing. This has a great effect on dimensional accuracy of final wire. A drawing zone feature
based model, allowed the examination of interaction evolution between wire and rolls geometry.
This analysis helps the user of this technology to make a proper change in the arrangement and
position of wire entering between rolls, or in the rolls configuration.
Abstract: Friction between powder and tools plays a major role during cold compaction of PM
components with results on the inhomogeneous densification. The present work deals with a new
method of compaction for PM components by using the friction force between die and compacts as
an active pressing force in order to reduce the density gradient. The proposal technique consists in
moving the container of the die, during pressing stage to the punch direction with a well determined
speed. As a result, the friction force acts in the same sense as the pressing load with better
distribution of powder flow during compaction. The experimental results of compaction parameters
versus density have proved the decreasing of the density gradient by increasing die/punch speed
rate. A sharp density gradient on the specimen height moving container contrarily to the punch.
Abstract: Present paper presents the results concerning the modeling process of extrusion of a
profile type “Yalle body”. COSMOS soft was used in order to simulate the extrusion process. 3D
model contains elements type SOLID, witch simulates the nonlinear behavior in the field of elasticplastic
domain. The constitutive equation of Iliusin and Dracker-Prager relation and Von Misses
criterion were used in simulation. The three dimensions model contains 1504 nods and 1750
elements in two different position of the die (optimum position and “out of optimum position”). For
both of die positions were presented variation of equivalent total stresses, tangential stresses in
different steps (1st step, critical step, and 20th step, by dividing the whole extrusion process in equal