Hadfield steel (110G13L) is the basic material for fast wornout items of mining equipment: beaters, hammers, liners, refractory plates of crushers and mills. By way of example, the effect of cold hardening was specifically analyzed on the rate of wear of mining equipment parts for various types of wear by hard (more than 1100 HV) and soft rock. A unique ability of that steel to resist shock wear is noted. It is shown that this steel exhibits low resistance to abrasive rock wear. Meanwhile wear by rock of hardness lower than steel (less than 1100 HV), may be substantially increased by pre-hardening of samples (up to 10-fold). In case of wear by high hardness rocks, shock impact that should contribute to hardening of the material, fails to increase abrasive wear resistance of Hadfield steel, and in that parameter it does not differ from the conventional medium carbon steel 45. Also, the authors of this article describe a technique they developed of high-temperature thermomechanical treatment of specimen of Hadfield steel (free forging at 1150-950ºC and subsequent quenching in water) and experiments in their abrasion. The results of tests show that hardness and wear resistance of Hadfield steel to hard abrasive (corundum 25A with aggregate hardness of ~2500 HV) increases with plastic deformation at HTMT. For maximum plastic deformation intensity (deformation magnitude of α = 2.25), reached in the experiments by the authors, wear resistance grew by 70% as compared to undeformed steel. The dependence is presented of wear resistance of steel on hardness, HV, achieved in the result of plastic deformation. Since a similar positive effect was obtained earlier by the authors for 35HGSA steel, also used in mining machinery, they conclude that the HTMT technique may be recommended for treating short lived parts of the mining and mineral processing equipment to increase their service life.
Regularities abrasion steel 110G13L with a significant load on the sample and impact. Found that increasing the load to the point where the voltage on the surface of the sample achieved a true rupture stress of the material, does not increase the wear resistance of steel. Shown that the impact and, therefore, have no hardening significant influence on the wear rate of steel in its work on the solids (granite, gabbro). In the case of soft rocks (marble) concomitant impact effect is exceeds durability of the material. Designed conclusion on whether the elements are made of mining and processing equipment from steel 110G13L depending on the hardness of the destroyed rock.
Taking a grinding of coal ball mill (type: BTM 400/800) operating without rocks as an example it is shown that a bombardment of the armour by grinding bodies made of steel 110G13L directly is capable to raise its hardness from 200 to 320HB at the depth of the cold-hardened layer up to 6,7 mm that will approximately 2 times increase its firmness to an abrasion. The time needed for the realization of an effective bombardment is 11 minutes, the period between strengthening cold – work hardenings is 25 days.
In article the analysis data of mechanical and metallographic researches of tangential rotary cutters of the Russian and foreign manufacturers is resulted. The reason of fragility of tangential cutters of the Russian manufacture is specified.
