A Novel Thermo-Optical Measuring System for the in situ Study of Sintering Processes

A novel thermo-optical measuring system (TOM) is described, which is able to monitor simultaneously and in situ thermal and optical properties of materials during the process of sintering. These are thermal diffusivity, heat capacity, thermal conductivity, transfer of heat radiation and scattering of light. Additionally, the geometric shrinkage is recorded by a non-contact optical dilatometer. The system has been designed for an efficient optimization of time-temperature-atmosphere cycles in sintering processes. Therefore, in the construction of the TOM system transferability of process parameters to other sintering furnaces is an important requirement. Due to this, compromises have been necessary in the layout of the measuring methods. Nevertheless, a high resolution was achieved for the distinction of different sintering states. Besides dilatometry, thermal diffusivity measurement by a laser-flash technique is a promising tool for the in situ monitoring of changes in microstructure during sintering. This revised version was published online in July 2006 with corrections to the Cover Date.