冷作模具钢Cr12Mo1V1因C含量和Cr含量高,铸态下在晶界析出大量网状共晶碳化物,锻造后仍会存在大量大块长条状碳化物,且呈带状分布,使钢的热塑性降低,易产生裂纹,限制了其应用.本文研究添加Mg对Cr12Mo1V1钢碳化物及热塑性的影响.随着钢中Mg含量增加,铸态下网状共晶碳化物被打断且被细化,使其在后期的锻造中更容易被打散.同时,锻态下碳化物的平均尺寸随着Mg含量增加而减小,呈均匀弥散分布.碳化物尺寸和分布状态的改善提高了钢的热塑性. Cold work die steel Cr12Mo1V1 due to the high C content and Cr content, a large number of reticular eutectic carbide precipitated in the grain boundary as cast, there will be a large number of large bar-shaped carbide after forging, and was banded, so that the steel Of the thermoplastic reduce, easy to produce cracks, limiting its application.This paper studies the addition of Mg on Cr12Mo1V1 steel carbides and thermoplastic With the increase of Mg in steel, the as-cast reticular eutectic carbide is interrupted and was thin So that it can be more easily disintegrated in the later forging.At the same time, the average size of carbide under forging decreases with the increase of Mg content, showing a uniform dispersion distribution.The improvement of the carbide size and distribution improves the steel Thermoplastic.