The mechanical failure of one cell is sufficient to lead to the end of service of a solid oxide fuel cell (SOFC) stack. Therefore, there is growing interest in gaining knowledge on the mechanical properties of the cell materials for stress analysis. This study compiles available data from the literature on the mechanical properties. Part I focuses on the most common materials used for the manufacturing of intermediate-temperature anode-supported cells, nickel and yttria-stabilized zirconia (Ni-YSZ) anodes, YSZ electrolytes, yttria (YDC) or gadolinia-doped ceria (GDC) compatibility layers and lanthanum strontium manganite (LSM) or lanthanum strontium cobalt ferrite (LSCF) cathodes. The properties for the simulation of stresses, i.e. thermal expansion, Young's modulus, Poisson's ratio, creep behaviour and strength are reported, with an emphasis on temperature and porosity dependence and the evolution upon aging or cycling when available. Our own measurements of two anodes, produced by different manufacturing routes are included.