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In Europe work is in progress to establish new standards for materials and it is very important that accurate data are used as a basis for property values in these standards. In addition reliable evaluation methods must be employed when the values are derived. A systematic evaluation method for yield strengths at elevated temperatures has been developed which is a modification of the ISO 2605/111 (ENV22605‐3) procedure. The method has been applied to a number of steel types and has proven to provide values in good accordance with experimental data. Comparisons with existing national and international standards showed the importance of using experimental values when establishing new standards. The method is intended for use in the standard developments by the European Committee for Iron and Steel Standardisation (ECISS).

A database for elevated-temperature tensile and creep properties for steels called HIGHTEMP has been developed. Materials that are included in the database are unalloyed, low alloyed, 12% chromium, and austenitic stainless steels, mainly of pressure vessel type. The data have been collected previously from Swedish industry and laboratories. Full metallurgical background information can be found in the system. This includes metallurgical casting and working processes, as well as product form, specimen geometry, heat treatment, room temperature tensile properties, microstructure, and testing methods. To illustrate the use of the database, the correlation between room-temperature tensile properties and creep properties have been studied for a few stainless steels. For 15Cr-15Ni-1Mo and 17Cr-12Ni-2Mo-0.15N, the creep rupture strength increases significantly with increasing room-temperature strength at testing temperatures below 750°C. In the same way, the creep ductility was reduced when the room-temperature strength was high. For 15Cr-15Ni-lMo, the variation in the room temperature tensile strength was related to a variation in the grain size.