Mechanical Properties Of High Manganese Steels Research Articles

Laser Rescanning for Enhancing Mechanical Properties of Laser-Directed Energy-Deposited High-Manganese Steels.

This study investigates the effects of laser deposition and laser rescanning (LR) on the microstructure and mechanical properties of high-manganese steel (HMnS) deposited by laser-directed energy deposition (L-DED) comprising 24 wt.% Mn. Four types of laser deposition and LR strategies were investigated: unidirectional L-DED scanning without laser rescanning, L-DED scanning with 90° alterations in the laser scanning path on each layer without laser rescanning, unidirectional L-DED with laser rescanning in the same direction, and L-DED with laser rescanning with 90° alterations in the laser scanning path. The L-DED-processed HMnS had only a few small pores and exhibited a microstructure without any serious defects such as cracks. Additionally, a strong fibrous texture along the <101>/building direction of the fully austenite phase was found. The mechanical properties (microhardness and tensile strength) of HMnS were improved by the LR with a grain refinement effect and fine solidification cell size due to the significantly faster solidification rate in LR than that in L-DED.

THE EFFECT OF CARBON AND NEGATIVE TEMPERATURE ON THE PHYSICAL, MECHANICAL AND OPERATIONAL PROPERTIES OF AUSTENITIC HIGH-MANGANESE STEEL

Purpose. It consists in determining the influence of carbon and manganese, concentrations of modifiers, test temperatures on the physical and mechanical properties and wear resistance of austenitic highmanganese steel Г13Л.&#x0D; Research methods. Determination of impact viscosity was carried out on the MK-30A pendulum probe, microhardness – on the PMT-3 device. The hydrostatic weighing method was used to determine the density. Microstructural analysis and study of non-metallic inclusions were carried out using metallographic and electron microscopes. Corrosion resistance was determined in a model environment with pH9, which corresponded to the production conditions of beneficiation processes of ferrous and non-ferrous metallurgy.&#x0D; Results. It was established that the best indicators of the properties of steel 110Г13Л are provided at average values of carbon and manganese concentrations within the standard. For parts that work under low shock loads, it is advisable to use austenitic wear-resistant steels with lower manganese concentrations and higher carbon concentrations within the standard chemical composition.&#x0D; Scientific novelty. New dependences on carbon influence, structural modification, non-metallic inclusions, and physical and mechanical properties of high-manganese steel were clarified and obtained. The strength limit of steel increases monotonically with increasing carbon content, and the dependences describing changes in plasticity, impact toughness, and hardness are extreme in nature.&#x0D; Practical value. A rational method of modification to improve the operational characteristics of steels is proposed. The influence of the test temperature on the impact toughness of steel with changes in carbon concentrations was studied, as the main indicator of the reliability of machine parts at low temperatures.

Complex Structural Effects in Deformed High-Manganese Steel.

The research presented in this paper is part of a larger project concerning deformation behavior, microstructure and mechanical properties of high-manganese steels with different chemical compositions and processed under various conditions. The current investigation deals with the development of microstructure and crystallographic texture of Fe-21.2Mn-2.73Al-2.99Si steel deformed in tension until fracture at ambient temperature. The deformation process of the examined steel turned out to be complex and included not only dislocation slip and twinning but also strain induced phase transformations (γ → ε) and (γ → α′). The formation of ε-martensite with hexagonal structure was observed within the microstructure of the steel starting from the range of lower strains. With increasing deformation degree, the α′-martensite showing a cubic structure gradually began to form. Attempts have been made to explain the circumstances or conditions for the occurrence of the deformation mechanisms mentioned above and their impact on the mechanical properties. The obtained results indicate that the strength and plastic properties of the steel substantially exceed those of plain carbon steels. Since both, mechanical twinning and the strain-induced phase transformations took place during deformation, it seems that both types of deformation mechanisms contributed to an increase in the mechanical properties of the examined manganese steel.

New insights into the properties of high-manganese steel

In the Collaborative Research Centre 761’s “Steel ab initio - quantum mechanics guided design of new Fe based materials,” scientists and engineers from RWTH Aachen University and the Max Planck Institute for Iron Research conducted research on mechanism-controlled material development with a particular focus on high-manganese alloyed steels. From 2007 to 2019, a total of 55 partial projects and four transfer projects with industrial participation (some running until 2021) have studied material and process design as well as material characterization. The basic idea of the Collaborative Research Centre was to develop a new methodological approach to the design of structural materials. This paper focuses on selected results with respect to the mechanical properties of high-manganese steels, their underlying physical phenomena, and the specific characterization and modeling tools used for this new class of materials. These steels have microstructures that require characterization by the use of modern methods at the nm-scale. Along the process routes, the generation of segregations must be taken into account. Finally, the mechanical properties show a characteristic temperature dependence and peculiarities in their fracture behavior. The mechanical properties and especially bake hardening are affected by short-range ordering phenomena. The strain hardening can be adjusted in a never-before-possible range, which makes these steels attractive for demanding sheet-steel applications.

Effect of tempering before quenching on the wear resistance of G13L steel

1. Prolonged tempering followed by quenching does not increase the wear resistance of parts of crushing-grinding equipment made of high-manganese steel. 2. The effect of prolonged tempering followed by quenching on the micro-and macrostructure of high-manganese steel is unsuitable for thick castings. 3. The mechanical properties of high-manganese steel are improved by tempering followed by quenching.