METASTABLE STRUCTURE OF AUSTENITIC MANGANESE ALLOY AND PROSPECTS FOR CREATION OF PARTS BASED ON IT

Comparative microstructural studies and mechanical tests of an experimental austenic manganese alloy and typical structural materials have been carried out. As a result of the research, relative data have been revealed, indicating high mechanical properties of the experimental alloy, which makes it possible to recommend it for machine parts operating at high load-speed operating conditions and temperature exposure up to 700 0C.

Using Acoustic Emission for Measuring Surface Roughness

This paper is focused on exploring and utilizing the acoustic emission and its behaviour during surface roughness measurement. Surface quality or coating properties significantly affect the reliability and durability of operations. Three samples were selected for an experiment to demonstrate the possibility of measuring the roughness of surface textures by means of acoustic emission method (AE). These samples were made of the following materials: sample A2 – EN 54SiCr6 steel formed in water, austenitized at 850 °C for 20 minutes, sample A3 – non-heat-treated spheroidal graphite cast iron, and sample B5 – abrasion resistant austenitic manganese steel. The surfaces were subjected to the same surface treatments (roughness Ra = 1.6–3.2 μm) and measured under the same conditions. All possible measurements were measured on both x- and y-axes. Final results are presented graphically. The measured AE values showed a visible effect in the AE signals due to the lack of surface roughness.

Engineering Method for Analysis of the Ability to Strain-Hardening of Steels

The strain-hardening ability has been estimated using a methodologically simple engineering criterion. A simple engineering method estimates the ability of metals and alloys to strain-hardening by the hardness increase determining. The Rockwell hardness has been measured at the bottom of the indentation cup of the Brinell press indenter. The strain-hardening tendency is investigated by the “two hardness-measuring instruments” method for two austenitic manganese steels, 110G13L and 110G6L, with different austenite stability to strain martensitic transformation. This hardness estimating method can be applied without making special samples and using deforming equipment.