Purpose: The aim of the paper is to determine influence of plastic deformation rate at room
temperature on structure and mechanical properties of high-Mn austenitic Mn-Al-Si 25-3-3
type steel tested at room temperature.
Design/methodology/approach: Mechanical properties of tested steel was determined
using Zwick Z100 static testing machine for testing with the deformation speed equal 0.008 s-1,
and RSO rotary hammer for testing with deformation speeds of 250, 500 and 1000s-1. The
microstructure evolution samples tested in static and dynamic conditions was determined in
metallographic investigations using light microscopy as well as X-ray diffraction.
Findings: Based on X-ray phase analysis results, together with observation
using metallographic microscope, it was concluded, that the investigated high-Mn
X13MnAlSiNbTi25-3-3 steel demonstrates austenitic structure with numerous mechanical
twins, what agrees with TWIP effect. It was demonstrated, that raise of plastic deformation
rate produces higher tensile strength UTS and higher conventional yield point YS0.2. The
UTS strength values for deformation rate 250, 500 and 1000 s-1 grew by: 35, 24 and
31%, appropriately, whereas in case of YS0.2 these were: 7, 74 and 130%, accordingly, in
respect to the results for the investigated steel deformed under static conditions, where
UTS and YS0.2 values are 1050 MPa and 700 MPa. Opposite tendency was observed for
experimentally measured uniform and total relative elongation. Homogeneous austenitic
structure was confirmed by X-ray diffractometer tests.
Research limitations/implications: To fully describe influence of strain rates on
structure and mechanical properties, further investigations specially with using transmission
electron microscope are required.
Practical implications: Knowledge about obtained microstructures and mechanical
properties results of tested X13MnAlSiNbTi25-3-3 steel under static and dynamic conditions
can be useful for the appropriate use of this type of engineering material in machines and
equipment susceptible to static or dynamic loads.
Originality/value: The influence of plastic deformation at room temperature under static
and dynamic conditions of new-developed high-manganese austenitic X13MnAlSiNbTi25-3-3
steels were investigated.
Effect of Cyclic Load Amplitude on the Evolving Characteristics of Accumulative Deformation in Subgrade Bed
