Manufacturing standards for Mn13 steel plates

At present, there is only a corporate standard; it’s not clear whether this is a new steel grade. I also don’t know what type of equipment this material is used in ? ?

These steels contain 10% to 15% manganese, and have a relatively high carbon content, generally ranging from 0.90% to 1.50%, with most having a value above 1.0%. Its chemical composition is (%): C 0.90–1.50, Mn 10.0–15.0, Si 0.30–1.0, S ≤ 0.05, P ≤ 0.10. This type of high-manganese steel is the most widely used; it is commonly employed to manufacture the bucket teeth of excavators, the crushing walls of cone crushers, the toggle plates of jaw crushers, the linings of ball mills, railway switch parts, sledge hammers, and hammer heads. The as-cast microstructure of high-manganese steel containing the above components is typically composed of austenite, carbides, and pearlite, and sometimes it also contains a small amount of phosphorus eutectic. When there is a large amount of carbides, they often appear in a network pattern at the grain boundaries. Therefore, high-manganese steel with its as-cast microstructure is very brittle and unusable, requiring solution treatment. The commonly used heat treatment method is solution treatment, which involves heating the steel to 1050–1100°C and holding it at that temperature to eliminate the as-cast structure and obtain a single-phase austenite structure; thereafter, it is quenched in water to maintain this structure at room temperature. After heat treatment, the strength, plasticity, and toughness of steel all increase significantly; therefore, this heat treatment method is also often referred to as water toughening. The mechanical properties after heat treatment are as follows: σb 615–1275 MPa, σ0.2 340–470 MPa, ζ 15%–85%, ψ 15%–45%, aKl 96–294 J/cm2, HBl 80–225. After solution treatment, a small amount of carbides remains undissolved in high-manganese steel; as long as this amount is low enough to meet the inspection standards, the material can still be used. When high-manganese steel with an austenitic structure is subjected to impact loads, plastic deformation occurs on the metal surface. As a result of strain strengthening, significant work hardening occurs in the deformed layer, leading to a substantial increase in the surface hardness. At low impact loads, it can reach HB300–400, while at high impact loads, it can reach HB500–800. Depending on the impact load, the depth of the surface hardened layer can reach 10–20 mm. A highly hard hardened layer can resist impact and abrasive wear. Material properties: High-manganese steel exhibits excellent wear resistance under conditions of severe impact and abrasive wear; therefore, it is often used in mechanical equipment in industries such as mining, construction materials, and thermal power generation to manufacture wear-resistant components. Under low-stress conditions, due to the weak work hardening effect, high-manganese steel cannot exhibit its material properties. The grades of high-manganese steel commonly used in China and their applicable ranges are as follows: ZGMn13—1 (C 1.10%～1.50%) is used for low-impact components, ZGMn13—2 (C1.00%～1.40%) is used for ordinary components, ZGMn13—3 (C0.90%～1.30%) is used for complex components, and ZGMn13-4 (C0.90%~1.20%) is used for high-impact components. The manganese content of all 4 grades of steel mentioned above is 11.0%–14.0%. During cold deformation under impact loading, the steel is strengthened due to a significant increase in dislocation density, as well as dislocation crossing, dislocation pile-up, and the interactions between dislocations and solute atoms. This is an important reason for work hardening. Another important reason is that high-manganese austenite has a low stacking fault energy, which makes it prone to the formation of stacking faults during deformation; this in turn creates conditions for the formation of ε-martensite and the generation of deformation twins. In the strain-hardened layer of conventional composition high-manganese steel, high-density dislocations, dislocation pile-ups, and entanglements can often be observed. The presence of ε-martensite and deformation twins makes it difficult to deform the steel, with the latter having a greater effect. All the aforementioned factors result in a high degree of strengthening of the hardened layer in manganese steel, leading to a significant increase in hardness. Manganese steel hardens very easily during processing, which makes it difficult to work with; the vast majority of it is produced as castings, with only a small amount being processed by forging. Manganese steel has good castability. Steel has a low melting point (around 1400°C), and the temperature difference between its liquid and solid phases is small (about 50°C). Steel also has poor thermal conductivity; as a result, molten steel is highly fluid and easy to pour into shapes. The linear expansion coefficient of high-manganese steel is 1.5 times that of pure iron and 2 times that of carbon steel; therefore, it experiences greater volume and linear contraction during casting, which makes it prone to stress and cracks. Many studies have been conducted on alloying, micro-alloying, adjusting carbon and manganese contents, and precipitation strengthening to improve the properties of high-manganese steel, and these methods have been applied in practical production. The emergence of metastable austenitic manganese steel allows for a significant reduction in the carbon and manganese contents in steel, while also increasing the rate of strain hardening of the steel. It can be used in applications with high, medium, and low impact loads, representing a new development in high-manganese steel. Application scope: It possesses high tensile strength, plasticity, and toughness, as well as being non-magnetic. Even when the parts become very thin due to wear, they can still withstand significant impact loads without breaking. It can be used to manufacture various impact-resistant and wear-resistant components, such as ball mill linings, excavator bucket teeth, and crusher jaws. It is generally used for castings with simple structures that require high wear resistance and low impact, such as linings, tooth plates, crushing walls, mill wall liners, roller sleeves, and shoveling teeth.

It should be suitable for low-temperature, non-corrosive media