Abstract Results of a field–experimental study on the applicability of continuous-cast medium-carbon 55 grade steel sparingly alloyed with chromium to the manufacturing of hardness IV and V class grinding balls 40 mm in diameter are presented. The possibility of the stable production of hardness IV class grinding balls is shown since chromium added in small quantities facilitates the hardness stabilization over the half of the ball radius and increases the volumetric hardness by 2–3 HRC figures. The established increase in the volumetric hardness did not allow for the HRC 57 level to be reached to certify the balls as the hardness V class products. Rational process variables have been recommended to ensure the production of 40-mm-in-diameter grinding balls for the V hardness class of continuous-cast medium-carbon 55 grade steel on the ShPS 30–80 ball-rolling mill.

中文翻译：

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55级连铸钢制造直径40毫米IV级和V级磨球可能性的探索

摘要 介绍了一项关于连续铸造含铬少量合金的中碳 55 级钢在制造直径为 40 毫米的硬度 IV 和 V 级磨球中的适用性的现场试验研究结果。显示了稳定生产硬度 IV 级磨球的可能性，因为少量添加铬有助于在球半径的一半内实现硬度稳定，并使体积硬度增加 2-3 个 HRC 数字。体积硬度的既定增加不允许达到 HRC 57 水平以证明球为硬度 V 级产品。