Showing 3 results for Trip Steel
Nosrati F., Zarei Hanzaki A.,
Volume 3, Issue 3 (12-2006)
Abstract
TRIP (TRansformation- lnduced- Plasticity) behavior is a powerful mechanism to improve mechanical properties. The basis of TRIP phenomena is the transformation of retained austenite with optimum characteristics (volume fraction, stability, size and morphology) to martensite during deformation at room temperature. Accordingly, the first requirement to obtain desired TRIP effects is to produce an appropriate microstructure. Thermo mechanical processing is an effective method to control the microstructural evolution thereby mechanical properties in TRIP steels. This work deals with a TRIP steel containing 0.2% C, evaluating the effects of straining before and during ?®a atransformation on its final characteristics, using hot compression tests. The results revealed that straining in the two phase region (dynamic transformation) not only reduces the ferrite grain size more significantly, but also increases the retained austenite volumefraction. Accordingly the final mechanical properties were also improved.
S. Gholami Shiri, Y. Palizdar, . A. Jenabali Jahromi, Eduardo F. de Monlevade,
Volume 15, Issue 3 (9-2018)
Abstract
The relation between microstructure and the fracture mechanisms of δ-TRIP steel with different Nb-content has been investigated using complementary methods of light microscopy, SEM, EDS, EBSD, X-ray phase analysis and tensile test. The results revealed a close dependency between the presences of constitutive phases i.e. ferrite, bainite, retained austenite and martensite and the mode and characteristics of fracture. All samples revealed almost different fractography pattern which could be associated to the effect of Nb microalloying element. The different fractography patterns were consisted of dimple rupture, riverside and Wallner lines pattern. The proportion of the cleavage fracture in comparison of dimple rapture increased by increasing the Nb-content due to the increase of primary martensite in the microstructure.
Ali Ebrahimpour, Amir Mostafapour, Naeimeh Hagi,
Volume 20, Issue 1 (3-2023)
Abstract
In this research, the effect of RSW parameters including current intensity, welding time and welding force (coded by A, B and C) on the radius, thickness and area of the nugget and the radius of the HAZ of TRIP steel joints was investigated by DOE and RSM. A 3D coupled thermal-electrical-structural FEM was used to model RSW. To validate the FE model, two TRIP steel sheets were welded experimentally. During welding, the temperature was measured and the results were compared with the FE results and a good agreement was obtained. The boundaries of the welding zones were determined according to the critical temperatures and the responses in all samples were calculated. Using analysis of variance, direct, quadratic and interaction effects of parameters on the responses were studied and a mathematical model was obtained for each response. The direct linear effects of all parameters on all responses were significant. But among the interaction effects, the effect of B×C on the nugget radius, the effect of A×B on the nugget thickness, the effect of A×B on the nugget area and the effects of A×B and B×C on the HAZ radius were significant. Also, current intensity had the greatest effect on all responses.
