Вплив нормалізації на кількісні параметри мікроструктури конструкційної сталі

• Дата: 2025
• Автори: Aftandiliants, Ye. G., Kvasnitska, Yu. G., Veis, V. I., Stepanova, T. V., Parkhomchuk, Zh. V., Kvasnitska, K. G.
• Формат: Стаття
• Мова: Українська
• Опубліковано: Physico- Technological Institute of Metals and Alloys of the NAS of Ukraine 2025
• Теми: сталь; хімічний склад; нормалізація; кількісний аналіз; ферит; перліт; зерно; розмір; коефіцієнт форми
• Онлайн доступ: https://momjournal.org.ua/index.php/mom/article/view/2025-4-5
• Назва журналу: Metal Science and Treatment of Metals

The article examines the impact of normalization on key quantitative parameters of the microstructure of as-cast structural steel, such as grain length, width, shape factor, grain area, and the total area of ferrite and pearlite. The capabilities of microstructure analysis using computer image analysis software are demonstrated, in comparison with the study of microstructure using reference scales. It was established that after normalization from 865 °C, the length and width of ferrite grains decreased by factors of 1.88 and 2.33, respectively; the shape factor decreased by 10–12%; the average area of a ferrite grain decreased by a factor of 4.78–5.18; while the total area of ferrite increased by a factor of 1.3–1.5. The length and width of pearlite grains decreased by factors of 2.21 and 2.01, respectively; the shape factor decreased by 3–12%; the average area of a pearlite grain decreased by a factor of 3.96–4.02; and the total area of pearlite decreased by 2–15%. It is shown that the refinement (dispersion) of the steel microstructure occurs due to an increase in the percentage of structural elements with smaller sizes. The proportion of ferrite grains with length and width in the range of 10–20 μm increased from 39% and 85% in the initial state to 91% and 97% after normalization, i.e., by a factor of 2.3 and by 14%, respectively. The proportion of grains with a shape factor of 2 increased by 8%, and the proportion of ferrite grains with an area in the range of 100–300 μm² after normalization reached 94%, which is 2.1 times higher than in the initial state. It was established that the distribution of pearlite in the microstructure of as-cast steel after normalization is characterized by the following: the proportion of pearlite grains with length and width in the range of 10–50 μm changed from 85% to 100% and from 95% to 100% of cases, respectively; the shape factor in 99% of cases was within the 1–4 range. The value of the average pearlite grain area in the as-cast state was within the 0–1750 μm² range in 98% of cases, while after normalization it was within 0–1250 μm² in 99% of cases. It is shown that the total area of ferrite in the as-cast state was 100% within the range of 15–30 μm², and after normalization within 15–45 μm². The total area of pearlite in a similar interval changed from 75–90 μm² to 60–90 μm², respectively. The materials of the article can be used by researchers for the quantitative analysis of the influence of external factors on the microstructure of metals and alloys.