TY - JOUR A1 - John, Elisabeth A1 - Jakob, Cordula A1 - Pott, Ursula A1 - Sando, Mona T1 - Repeatability and reproducibility challenges of isothermal heat flow calorimetry with in situ mixing N2 - Isothermal heat flow calorimetry evaluates heat development during binder reactions. It distinguishes between in situ calorimetry, where mixing occurs within the device, and ex situ calorimetry, involving externally mixed samples. Despite ex situ calorimetry being a standard method in binder research, in situ calorimetry is underutilized. This paper aims to promote its adoption by summarizing challenges related to repeatability and reproducibility and offering solutions. The initial section addresses repeatability issues caused by preventable errors, providing a structured guide for experimental design. It was found that water leakage had minimal impact, and sample size is crucial for data robustness. The second section examines operational challenges, revealing that frictional heating, affecting recorded heat, can be minimized with an optimized mixing protocol. The final part highlights that significant errors in measured data stem from signal delay and heat loss, offering methods to correct these issues for improved reproducibility in in situ calorimetric experiments. KW - In situ calorimetry PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628431 DO - https://doi.org/10.1016/j.cemconres.2025.107872 SN - 1873-3948 VL - 194 SP - 1 EP - 11 PB - Elsevier Ltd. AN - OPUS4-62843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -