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本文针对我国目前大型饼类锻件探伤超标的质量问题，解剖分析了钢锭和报废锻件。常温模拟研究了大压下量镦粗过程的变形分布规律。在压下率△Ｈ／Ｈ０＜６０％前，难变形区形状和大小基本不变化；△Ｈ／Ｈ０＞６０％后，上、下难变形区逐渐减小，并且始终不相交，也不相互插入。在锻件心部相对狭窄的变形区形成了剪切带，这是产生裂纹的重要原因之一。高温模拟研究了镦粗变形过程中夹杂的行为，了解了塑性夹杂物被压扁，夹杂周围存在应力、应变集中导致夹杂性裂纹产生的过程；发现了由于温度变化，夹杂和基体材料的变形性能改变致使裂纹产生有三种形式。对多个塑性夹杂则发生相连、汇合。这是大型饼类锻件产生夹杂性裂纹和探伤超标的重要原因，并对相应的工艺改进措施进行了生产考证。
In this paper, for the current large-scale inspection of large-scale cake forging quality problems, anatomical analysis of ingots and scrap forgings. At room temperature, the deformation and distribution of upsetting process were studied. The shape and size of the difficult-to-deformable zone basically did not change before the reduction rate of △ H / H0 was less than 60%. After ΔH / H0> 60%, the upper and lower difficult-to-deformable zone gradually decreased and did not intersect or reciprocally insert. In the forging heart of the relatively narrow deformation zone formed shear zone, which is one of the important reasons for the crack. The behavior of inclusions during upsetting deformation was studied by high-temperature simulation. The plastic inclusions were crushed, and the stress and strain concentrated around the inclusions led to the process of inclusions cracking. It was found that due to temperature changes, inclusions and the deformation properties of matrix materials There are three forms of change that cause cracks. A number of plastic inclusions are connected, convergence. This is an important reason for the occurrence of inclusion cracks and flaw detection in large-sized cake forgings and the production of the corresponding process improvement measures.