Universite de technologie de Belfort-Montbeliard

About: Universite de technologie de Belfort-Montbeliard is a education organization based out in Belfort, France. It is known for research contribution in the topics: Coating & Microstructure. The organization has 1087 authors who have published 2593 publications receiving 47819 citations.

Modification of thermal barrier coating architecture by in situ laser remelting

Abstract: Yttria partially stabilized zirconia thermal barrier coatings (TBCs) are widely used to protect components of aero gas turbines against high heat fluxes and hence increase their properties by reducing their in-service temperature. However, these coatings degrade in service conditions. Therefore, manufacturing TBC which present both low thermal conductivity and high life-time is a real challenge. Engineering the coating architecture by an adapted process is a prerequisite to modify TBC characteristics. In this study, laser remelting was combined to thermal spraying in order to modify the TBC properties. In situ laser treatment (i) changes structure from lamellar to dendritic columnar; (ii) generates a pore architecture less sensitive to sintering, maintaining the TBC thermal and mechanical properties during thermal treatments at high temperatures; (iii) improves the thermal insulation properties of the TBC by decreasing its thermal conductivity of about 30%; (iv) decreases its permeability permitting to reduce oxidation and corrosion phenomena of the underneath layers and substrate; (v) increases the resistance to isothermal shocks (with the possibility to double the number of cycles); (vi) conducts to a metastable tetragonal phase more stable during thermal shocks; (vii) without modifying the elastic response of the deposit.

Representing and Tracking of Dynamics Objects using Oriented Bounding Box and Extended Kalman Filter

Abstract: Representing and tracking of dynamics objects is one of the main parts of autonomous navigation in urban areas. In the framework of the development of a multiple objects tracking system using multisensor fusion, this paper presents an oriented bounding box (OBB) representation with uncertainty computation as well as a model for object tracking. The uncertainty computation method, which takes into account laser range finder sensor uncertainty and object's relative position, is evaluated. The influence of this uncertainty on the accuracy of the estimation is shown. The tracking model, based on the extended Kalman filter is tested and evaluated using the OBB object's representation.

Temperature dependence of microstructure and hardness of vacuum plasma sprayed Cu–Mo composite coatings

Abstract: A copper baseplate has been commonly adopted as a heat spreader material for power modules. However, the coefficient of thermal expansion (CTE) mismatch between copper and Si has always been a troublesome problem and the primary disadvantage of using a copper baseplate because the interface between the substrate and the heat spreader is one of the main failure sources of a power module. To solve this problem, the tailoring of a Cu–Mo composite material with high thermal conductivity and suitable thermal expansion coefficients was suggested by thermal spray process which makes it possible to easily fabricate components of functionally graded materials (FGMs) and allows the multiple steps of powder production, molding, degassing and consolidation to be reduced into a single processing step. By utilizing the vacuum plasma spraying technique, dense and well-distributed Cu–Mo metal matrix composite coatings without oxides and amorphous phase were obtained. Vertically grown intralamellar columnar structure, which is promising for increasing the heat transfer, was also observed in plasma sprayed Cu–Mo metal matrix composite coatings. Microhardness of Cu–Mo composite coatings follows a rule of mixture based on the volume fraction and fits nicely to a linear relation regardless of different measured temperatures.