The precursor and inventor who patented in 1882 a new grade with Manganese Mn content in an average concentration of 12% was Robert Abbott Hadfield, an English metalurger born on November 28, 1858, in Sheffield, who made a breakthrough by discovering the extraordinary property of steel - high abrasion resistance due to curing of the product with pressure, by adding to the steel with a carbon range of 1.00-1.25% Manganese at a ratio of 1:10.
The newly developed grade has been a great success and is still used today in the manufacture of abrasion-resistant components, which has pushed economic development in many countries, and elements so far made from other abrasion resistant steels have been displaced because they have a shorter life time.
Apart from the very high content of Carbon and Manganese in the chemical composition, Hadfield Steel does not have more of the alloying properties than Silicon itself, which is usually added as standard in other grades. Some equivalents may have a small range of chromium, nickel and copper.
High-manganese steel in Poland was given a name 11G12, which is not covered by departmental and state standards and only complies with industry standard BN-68/0631-04, BN-90/0631-03. Its equivalent according to the German DIN standard is – X120Mn12.
Hadfield's steel is one of the few carbon alloy steels with an austenitic structure. It acquires its properties only after being oversaturated in water or oil (at smaller details) at the range from 1000 to 1050 ℃. High-manganese steel products are non-magnetic, but in tempered condition, poorly heat-treated or cold-hardened conditions the steel exhibit some ferromagnetic properties.
In addition to the abrasion resistance, the Hadfield steel exhibits pressure and impact resistance, but at friction and abrasion-free grinding, the product does not cure, in the result of which the surface may be subject to abrasion. Referring to extremely high abrasion resistance, the other side of the coin is extremely difficult mechanical processing of the material.
To prepare a product for mechanical treatment, the Hadfield steel is intentionally heated to a temperature of 500 ℃ with the next rapid cooling in water, which gives the manganese steel a martensitic structure.
Except for the 11G12 grade, to hard-wearing grades was also counted extremely rare 55G15 grade, according to BN-68/0631-03.
Sheets, plates, forgings and hot-rolled bars from wear-resistant High-manganese steel
The above-described high-manganese hard-wearing steels are defined by the Industry Standard BN-68/0631-03, BN-68/0631-04, BN-90/0631-04 and PN-EN ISO 4957 standard, according to which the following are delivered: