# Changes in Mechanical Properties of Medium Manganese Steel After Forming, Press Hardening, and Heat Treatment

## TL;DR

This paper studies how forming, press hardening, and heat treatment affect the strength and ductility of a specific medium manganese steel.

## Contribution

The study introduces a new process using intercritical annealing to achieve high tensile strength and elongation in medium manganese steel.

## Key findings

- The highest tensile strength achieved was 1262 ± 6 MPa.
- Maximum elongation reached was 16 ± 1%.
- Intercritical annealing significantly influenced the microstructure and mechanical properties.

## Abstract

Solutions and new processes are continually being developed to produce components demonstrating high strength and elongation. This paper focuses on medium manganese steel with a composition of 0.2% carbon, 3% manganese, and 2.15% aluminium (by weight percent). The mechanical properties of the steel and the effect of aluminium and manganese on the microstructure are investigated. The steel sheets are shaped into omega profiles using a press tool, followed by the intercritical annealing of the samples to enhance their ductility. Before the experiment, the anticipated values were a tensile strength (UTS) of approximately 1100 MPa and elongation within 30–35%. A key objective was to achieve a microstructure that incorporates residual austenite. The experimental parameters were carefully derived from an extensive exploration to identify potential weaknesses in the experiment. The main parameters selected were the intercritical annealing (IA) temperature and IA dwell time. The results revealed that the highest recorded UTS was 1262 ± 6 MPa, while the maximum elongation achieved was 16 ± 1%.