The overall objective of AD ASTRA is the development of Accelerated Stress Test (AST) protocols that allow quantitative identification and prediction of critical degradation mechanisms, correlating them with overall performance variables in selected solid oxide fuel cell/electrolyser (SOFC/SOEC, or SOC) stack components (fuel electrode, oxygen electrode and interconnect). These will build firstly on the analysis of numerous field-tested samples of SOC stacks provided by the industrial partners, followed by applying existing and developing improved testing and modelling methods based on ex-situ component ageing and aggravated stack testing.