Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: nanobainitic steels

Sortuj według:

Ogranicz wyniki do:

Evaluation of cracking risk of 80MnSi8-6 nanobainitic steel during hot forging in the range of lower temperature limits

Lisiecka-Graca Paulina, Lisiecki Łukasz, Zyguła Krystian, Wojtaszek Marek

Materials Science Poland

2024

Vol. 42, No. 1

171--185

Nanobainitic steels exhibit an exceptional combination of high strength, good plasticity, impact toughness, and wear resistance. They are suitable for the production of large mass components through the open-die forging process. Subsequently, the forgings are air-cooled. An obstacle of this method is the extended time required for the large forgings to undergo a bainitic transformation, making the industrial implementation of this process economically unjustifiable. Nevertheless, nanobainitic steels also allow for the open-die forging of small batches of structural elements with high property requirements. A technological limitation lies in the necessity of performing a series of operations, leading to a prolonged processing time dependent on the shape of the product and the degree of deformation. Therefore, inter-operational reheating is often necessary, incurring costs and time consumption. This is particularly relevant to forgings with a mass ranging from a few to several dozen kilograms, which, due to their low thermal capacity, rapidly dissipate heat to the surroundings and tools. Designing an economical process with a limited number of reheating cycles requires advanced knowledge of material behavior under thermo-mechanical deformation parameters, including boundary conditions where a significant decrease in plasticity occurs and the risk of crack initiation. To obtain this information, a comprehensive analysis of the influence of thermo-mechanical parameters applied during the deformation of nanobainitic steel at relatively low temperatures on the flow characteristics and crack formation was conducted. To achieve this goal, the Digital Image Correlation method, the finite element method modeling considering damage criteria, and the macrostructural evaluation of deformed specimens were employed.

Characteristics of Fusion Welded and Friction Welded Joints Made in High-Carbon Nanobainitic Steels

Węglowski M. S., Grobosz W., Marcisz J., Garbarz B.

Biuletyn Instytutu Spawalnictwa w Gliwicach

2018

Vol. 62, No. 4

7--15

Intense research on the metallurgy of iron alloys have recently resulted in the development of technologies enabling the making of high-carbon nanobainitic steels. Because of their chemical composition, the above-named steels belong to hard-to-weld materials. To identify the possibility of welding such steels using arc-based methods and welding in the solid state it was necessary to make test joints and perform related metallographic tests. The test results revealed that it is possible to obtain both fusion and pressure welded joints if the process was performed in the softened state, i.e. before the final heat treatment. Afterwards, joints should be subjected to a heat treatment ensuring the obtainment of a previously assumed microstructure and required hardness distribution in the weld and HAZ.

Intensywne prace badawczo-rozwojowe w zakresie metalurgii stopów żelaza doprowadziły w ostatnim czasie do opracowania technologii wytwarzania wysokowęglowych stali nanobanitycznych. Stale te ze względu na skład chemiczny należą do materiałów trudno spawalnych. W celu określenia możliwości ich spawania metodami łukowymi oraz zgrzewania w stanie stałym, wykonano złącza próbne oraz przeprowadzono badania metalograficzne w ich obszarze. Wyniki badań wykazały możliwość uzyskania złączy spawanych i zgrzewanych pod warunkiem prowadzenia procesów łączenia blach w stanie zmiękczonym, tj. przed finalną obróbką cieplną. Następnie złącza można poddać obróbce cieplnej gwarantującej uzyskanie założonej mikrostruktury i rozkładu twardości w spoinie i w strefie wpływu ciepła.