نوع مقاله : مقاله مروری پژوهشی
موضوعات
عنوان مقاله English
نویسندگان English
This article deals with the impact and how to improve the fatigue strength of spring steel. In this regard, the basic and modern methods that include reducing the size of inclusions, decrease grain size, reducing the depth of decarburization, increasing the surface quality and desirable microstructure due to heat treatment are investigated and compared. In relation to the fatigue strength of spring steel, the microstructure of tempered martensite or fine bainite is used in the industry. The experimental results show that the multi-phasing of spring steel from the microstructures of tempered martensite, fine bainite and retained austenite in Q&P and Q&B heat treatment methods or a combination of these two methods will bring the best micro-alloy microstructure for spring steel. The concerned evaluation methods were: different microstructures caused by heat treatment and reducing the size of non-metallic inclusions in steel. The experimental results show that if the steel is clean (free of inclusion), the microstructure would play a dominant role in increasing the fatigue life.
کلیدواژهها English