Modern material science is of great importance for research and development projects in many areas. For example, the increase of the efficiency of thermal energy conversion processes and the necessary increase in process temperature requires the development of high-temperature stable materials. Under operating conditions, the temperature of the ceramic thermal barrier coating (TBC) of modern gas turbine blades in some cases is far above the melting point of the metallic body material. In contrast, with additive manufacturing techniques, such as the laser sintering method, material is melted locally using a laser beam at high temperatures. The goals of current development projects are to increase precision and improve process control.
In the applications mentioned here, as well as in many other fields, precise knowledge of the material parameters at high temperatures above 1000 °C and up to over 2000 °C is required to reliably predict the behavior of various materials under extreme operating conditions. For this purpose, the thermal conductivity and the specific heat capacity are particularly relevant. The laser flash method can be used as a verified measuring method to determine thermal conductivity even at high temperatures above 2000 °C. Using the method of differential scanning calorimetry (DSC), the specific heat capacity can only be measured at temperatures below 1000 °C up to now. Today, thermocouples are used in most DSC applications for the necessary temperature measurement. However, these thermocouples are unsuitable for higher temperatures. Therefore, there is still a need for a reliable measurement method that can provide validated information about the specific heat capacity of material samples at temperatures far above 1000 °C.
In order to fill this knowledge gap in the future, the goal of the project Optical Differential Calorimetry for Modern Materials Research at High Temperatures (OptiMa) is to develop a DSC method for measuring the specific heat capacity at temperatures between 1000 °C and over 2000 °C. In this newly developed DSC setup, various optical detectors, such as radiation thermometers and thermographic cameras, are tested and analyzed to collect the necessary temperature information without using fault-prone thermocouples. In addition, several methods of sample heating will be tested, such as inductive heating and laser heating. Furthermore, in order to reduce the number of necessary measurement cycles, it is planned to use a three-cell sample holder design for the DSC measurement [1][2].
The poster presents the theoretical and practical requirements of the designed method together with numerical simulations of the measurement process.

Acknowledgment
This Project (contract number: 13FH070KX0) has been sponsored as a part of the funding program Forschung an Fachhochschulen by the German Federal Ministry of Education and Research (BMBF).
Significant references
1. B. Wunderlich, J. Therm. Anal., vol. 32 (1987), pp. 1949-1955.
2. Y. Takahashi, Pure Appl. Chem., vol. 69 (1997), pp. 2263-2269.