Структура, как основа системы качества в трубном производстве

Abstract

Standards currently used for a quality assessment of tube plate have been out of date and cannot be used for the description of its quality and application properties. The hardware-software motorized device Thixomet Smart Drive for an objective quantitative estimation of all types of structural heterogeneity in modern tube steels – microstructural banding, general anisotropy, blocks of bainite with lath morphology, centerline segregation - was developed, realized and installed in tens enterprises and organizations. All developed standards or are unique and have no analogs (general anisotropy and blocks of bainite with lath morphology), or are compatible but surpass in efficiency and objectiveness of quality estimation operating local (GOST 5640) and foreign (ASTM 1268, GB/T 13298) standards. It was established that structural heterogeneity estimated by a volume fraction and size of extended areas of bainite with lath morphology streamlined along rolling direction adequately describes mechanical properties at tensile and impact bending tests of pipeline steels with yield strength from 485 up to 625 N/mm2. The found "structure- properties" relationships can be used as a background for quality estimation system including acceptance test of steel products between suppliers and consumers of the plate, and also for the improvement of through technology of its production.