Tecnun

About: Tecnun is a based out in . It is known for research contribution in the topics: Sintering & Ferrite (iron). The organization has 202 authors who have published 129 publications receiving 2122 citations.

Analysis of different acicular ferrite microstructures in low-carbon steels by electron backscattered diffraction. Study of their toughness behavior

Abstract: Acicular ferrite formation, promoted by the intragranular nucleation of ferrite plates, is well known to be beneficial for achieving a good combination of mechanical properties. However, the set of microstructures that can be obtained during the subsequent development of the transformation from the primary plates generated at particles can be quite complex and depends on a certain number of variables: steel composition, temperature range, prior austenite grain size, and particle density. In the present work, acicular ferrite microstructures have been produced by isothermal treatments in three different steels with different active particle types and densities. The morphology of the obtained intragranular microstructures has been found to depend on the steel composition, the prior austenite grain size, and the density of particles able to promote intragranular nucleation. Electron backscattered diffraction (EBSD) techniques have been used to define the microstructural unit controlling toughness in these types of microstructures.

Correlation between nanoindentation and tensile properties influence of the indentation size effect

Abstract: The nanoindentation test has become one of the most broadly expanded techniques used to measure the mechanical properties in a sub-micron range. However, the interpretation of the data is very difficult due to the Indentation Size Effect (ISE). The ISE can be defined as an increase of the nanohardness by decreasing the indentation depth of the test. In the present work, the ISE of different metals has been studied by performing nanoindentation tests at different imposed depths. Furthermore, tensile tests of these materials have been carried out in order to determine empirical relations between the nanoindentation test results and the tensile properties.

Wear behaviour of eutectic and hypereutectic Al-Si-Cu-Mg casting alloys tested against a composite brake pad

Abstract: The wear resistance of nine eutectic and hypereutectic Al–Si alloys with various compositions and processing routes was studied. Testing was conducted using a pin-on-disc configuration and two different testing speeds. At lower disc speed, the influence of the composition and alloy processing was very strong and a severe wear transition was observed for the alloys with low fractions of primary silicon particles. At higher disc speed, wear of all the alloys but one was very low. The high wear alloy had a high silicon content and a very large primary silicon size; the accelerated wear was caused by cracking and fracture of the large silicon particles upon impact with the abrasive disc material at the higher speed.

Parallel RRT-based path planning for selective disassembly planning

Abstract: The planning of disassembly sequences requires the identification of the extraction trajectories of the different parts or assemblies. The failure to find these trajectories can make a planner fail to generate correct sequences or not evaluate potential solutions. In this paper, we analyze the disassembly path-planning problem, its relation to the general path-planning problem and the main differences between both of them, such as the lack of a target configuration. We present a modification of the rapid-growing random tree-based algorithm (RRT) that addresses these differences. RRTs are easily parallelized so we analyze two different parallelization methods using dual-core-based CPUs as well as the impact of the target selection probability of the algorithm in execution time. The method described is applied to several real-world and synthetic examples.