140CrNiMo锻造半钢轧辊的试制

Trial production of 140CrNiMo forging adamite rolls

介绍了140CrNiMo锻造半钢轧辊的生产试制情况。采用浇铸轧辊工装铸造半钢毛坯，铸坯为轴类形状，提高了铸坯利用率。锻前采用低温长时间加热扩散；锻造时使用上平、下V型砧（型砧越旧越好）直接拔长轧辊铸坯，严格控制压下量，有效减少了拉应力而增加压应力，较好地解决了锻造半钢轧辊锻造时的裂纹问题。锻造比不小于2，较好地改变了碳化物的分布状态，大幅度提高了材料的综合力学性能。终锻温度为900℃，锻后空冷到450～500℃进炉热处理。锻后进行正火＋球化＋扩氢退火热处理，最终热处理后，辊身组织为细珠光体＋二次碳化物，制造出合格的锻造半钢轧辊。

The trial fabrication of 140CrNiMo forging adamite rolls was introduced. The adamite blanks were cast with roll cast mould and the cast blanks were of shaft shape that could improve the blanks utilization rate. The heating process with low temperature for a long time was undertaken prior to the forging. Cast rolling blank was directly stretched with upside flat and underside ＂ V＂ swage anvils （the older the anvil was, the better it was） . The reduction was well controlled and tensile stress was effectively reduced while the compressive stress was increased. By this way, the failure of surface cracks of forging adamite rolls was solved successfully. The forging ratio was not less than 2, while the distribution of carbide was improved and the comprehensive force properties of the material were significantly increased. Final forging temperature was 900℃. The rolls will be air cooled to 450～500 ℃ after forging and before heat treatment. The process of heat treatment after forging was normalizing ＋ spheroidizing ＋ annealing by expanding hydrogen. After final heat treatment, the matrix of roll barrel was fine pearlite ＋ secondary carbide. Qualified forged adamite rolls were produced successfully.