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In this work a hot forming strategy, consisting of forging and hot rolling, to homogenize casted blocks of high-manganese steels with 0.3 % carbon and 22 % manganese is introduced. The resulting distribution of carbon and manganese is evaluated by microprobe scans. The micro-segregation of manganese could be reduced from 7 weight percent to 2. To create the obtained hot forming strategy hot compression tests have been carried out. The deformation behavior has been characterized for two steels with 22 % manganese and between 0.3 and 0.7 % carbon content in the temperature range between 700 and 1200°C and strain rates between 0.1 and 10 s-1.

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In this work compression tests were performed to characterize the flow behavior of three different high manganese austenitic steels (HMS) in dependence of temperature (300–1200 °C) and strain rate (0.1‐10 s−1). True stress‐true strain curves were calculated from the experimental data. Temperature compensation was applied to remove the effects of adiabatic heating. At 300 °C the influence of strain rate is small but rapidly increases with temperature. DRX can be observed above 1100 °C for all HMS with 23 wt% Mn starting from the smaller strain rates. Higher Mn contents seem to promote DRX which occurs first for a 28 wt% Mn steel at 1000°C. While an increasing Mn content decreases the maximum flow stress at smaller temperatures, the opposite is found at temperatures above 700 °C. Carbon influences the stress‐strain curves mainly at temperatures below 700 °C as it raises the maximum stress levels. At temperatures above 1100 °C all three investigated HMS show similar flow curves. By increasing the temperature from 300 °C to 1200 °C the initial flow stresses are reduced by a factor of ten. The maximum flow stress levels are decreased by a factor of eight (Fe‐Mn28‐C0.3), ten (Fe‐Mn23C0.3) and eleven (Fe‐Mn23C0.6).

In this paper, the capabilities of the thin strip (twin roller) casting method to produce high manganese steel strip are examined. For this purpose a FeMn22C0.6 strip has been cast both using a lab‐scale twin roll casting line and a more conventional process chain. The experiments show that the production of high manganese steel strip is feasible with both methods. Differences become apparent in the microstructure and chemical composition. While the strip which was produced by ingot casting and hot forming shows a homogenous grain distribution, the thin‐strip‐cast one shows a typical casting microstructure, consisting of dendritic and globulitic structures. In addition, the thin‐strip‐cast steel contains the accurate carbon content, while the hot forming route led to a loss of carbon, which influences the mechanical properties. The good potential of thin‐strip casting of high manganese steels, although it still has to be improved, is confirmed.