Bulk Observation of Metallic Powder Sintering: First in situ Synchrotron Micro-Tomograhic Results

摘要

The mechanisms involved in the sintering of complex materials like iron-based systems are still poorly understood. New information can be obtained on the microstructural evolution during sintering by using synchrotron imaging technique. Using micro-tomography, a three-dimensional characterisation can be accomplished. Indeed, microstructural parameters such as pore shape, neck size or relative density of the powder are investigated after different sintering steps. The investigated samples are an industrial powder (Distaloy AE) and a model material: copper powder with nearly spherical particles. For such absorbing materials high energy micro-tomography conditions are required. Moreover, to perform some in-situ sintering experiments, one has to be capable to record complete micro-tomography in very short times, of the order of about one minute. Therefore, fast micro-tomography has been developed at the European Synchrotron Radiation Facilities at Grenoble (France). The first results clearly show that this synchrotron imaging technique is well adapted to investigate sintering, in terms of both spatial and temporal resolutions. The first experimental results and the role of physical parameters, such as die compaction stress or temperature, are presented.