| Autor: |
Abdellah, Mohammed Y., Alharthi, Hamzah, Alfattani, Rami, Suker, Dhia K., Abu El-Ainin, H. M., Mohamed, Ahmed F., Hassan, Mohamed K., Backar, Ahmed H. |
| Předmět: |
|
| Zdroj: |
Metals (2075-4701); Mar2024, Vol. 14 Issue 3, p352, 14p |
| Abstrakt: |
Temperature has a great influence on the mechanical properties of ductile cast iron or nodular cast iron. A thermomechanical treatment was carried out at various elevated temperatures of 450 °C, 750 °C and 850 °C using a universal testing machine with a tub furnace. Specimens were held at these temperatures for 20 min to ensure a homogeneous temperature distribution along the entire length of the specimen, before a tensile load was applied. Specimens were deformed to various levels of uniform strain (0%, 25%, 50%, 75%, and 100%). These degrees of deformation were measured with a dial gauge attached to a movable cross plate. Three strain rates were used for each specimen and temperature: 1.8 × 10 − 4 s − 1 , 9 × 10 − 4 s − 1 and 4.5 × 10 − 3 s − 1 . A simple analytical model was extracted based on the CT tensile test geometry and yield stress and a 0.2% offset strain to measure the fracture toughness (JIC). To validate the analytical model, an extended finite element method (XFEM) was implemented for specimens tested at different temperatures, with a strain rate of 1.8 × 10 − 4 s − 1 . The model was then extended to include the tested specimens at other strain rates. The results show that increasing strain rates and temperature, especially at 850 °C, increased the ductility of the cast iron and thus its formability. The largest percentage strains were 1 and 1.5 at a temperature of 750 °C and a strain rate of 1.8 × 10 − 4 s − 1 and 9 × 10 − 4 s − 1 , respectively, and reached their maximum value of 1.7 and 2.2% at 850 °C and a strain rate of 9 × 10 − 4 s − 1 and 4.5 × 10 − 3 s − 1 , respectively. In addition, the simple and fast analytical model is useful in selecting materials for determining the fracture toughness (JIC) at various elevated temperatures and different strain rates. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
