Виявлення прихованих дефектів на поверхні ливарних виробів

• Дата: 2025
• Автори: Сіренко, К.А., Мазур, В.Л.
• Формат: Стаття
• Мова: Українська
• Опубліковано: Physico-technological Institute of Metals and Alloys 2025
• Теми: ливарне виробництво; виливки з чавуну і сталі; дефекти поверхні; способи виявлення; дробо-струменева обробка
• Онлайн доступ: https://www.metalsandcasting.com/index.php/mcu/article/view/310
• Назва журналу: Metal and Casting of Ukraine

The features of the Ukrainian national standard DSTU 9051:2020 “Iron and steel castings. Defects. Terms and definitions of concepts” are considered. The classification of defects on the surface of castings adopted in this standard is analysed from the point of view of the possibilities of detecting hidden violations of the integrity of the surface layers of metal and recommendations for preventing the development of these defects in castings during their operation. In the process of developing this standard, in order to increase its informativeness, it is proposed to supplement the definition of the causes and mechanism of defect formation on the surface of castings with photographs of the microstructure of the surface layer of metal in the areas where defects occur. The insufficiency of coverage of the topic of preventing surface defects in cast iron and steel castings in modern technical literature is demonstrated. The example of the production and operation of railway brake pads demonstrates the relevance of scientific and industrial research into the prevention of defects on the surface of brake pads due to their negative impact on the formation of creepers, craters, welds, and other defects on the surface of rolling stock wheels and railway rails. This significantly worsens the technical and economic performance not only of foundries, but also of consumers of foundry products, in particular the railways. The inefficiency of shot blasting castings to detect and remove defects on their surface compared to shot peening has been demonstrated. The necessity of using shot peening (shot blasting) of castings in the manufacture of critical products has been demonstrated. In accordance with the practice of foundries, round steel shot with a diameter of 1.8 to 3.2 mm is effective for shot blasting these products. Recommendations are given on the mandatory shot blasting of cast iron brake pads during their manufacture. The technical specifications for cast iron brake pads for railway rolling stock must regulate the requirements for shot blasting their surfaces to detect and remove hidden defects.