42CrMo轴承环件是高铁动车和风力发电等装备制造领域关键承载、传动构件。基于环件铸辗复合成形技术开展42CrMo钢轴承环件离心铸造、热辗扩成形及淬回火试验研究，分析高温变速进给时辗扩成形环件的微观组织及力学性能，并对后续淬回火过程组织性能演变规律进行探讨。结果表明，成形环件沿径向厚度区域晶粒得到细化，环件近中层和最小宽展处伴有不规则和等轴状的粗大晶粒;强度、硬度值较高，塑、韧性偏差，拉伸和冲击断口形貌表现为韧窝均聚集在剪切唇上，以解理断裂形式为主。530 ℃回火时沿环件壁厚方向未观察到碳化物，塑韧性仍较低;590 ℃回火后析出少量细小、弥散分布的碳化物颗粒，各项力学性能指标均满足标准要求，拉伸断口的韧窝数量多、直径大，冲击断口也比530 ℃时的平整，韧窝分布更加均匀，使得铸辗复合成形轴承环件的强度和塑韧性得到良好的配合。

The 42CrMo bearing ring is widely used in industry fields,especially as key components in high-speed rail,motor car and wind power,etc. Based on the cast-rolling compound forming of rings,the hot rolling for centrifugal casting 42CrMo bearing,and subsequent quenching and tempering are studied. The microstructure and mechanical properties of the rolled ring are analyzed,and their evolution laws during quenching and tempering are discussed. The results show that the grain is refined through the whole thickness of the rolled ring,while irregular and equiaxed coarse grains are found near the middle-layer and minimum spread. The values of strength and hardness are high,and plasticity and toughness are low. The fracture appearances of both tensile and impact are characterized by dimple mainly gathered in shear lip,which display cleavage fracture. After tempering at 530 ℃,the carbide does not be found and the plasticity and toughness remain low. A little of fine and dispersed carbide particle is precipitated at 590 ℃ tempered. Also,the mechanical properties satisfy the standardized demands of production. In these conditions,the tensile fracture has a few of dimples with a large diameter,and the impact fracture is smooth with homogeneous dimple than that at 530 ℃ tempered. So a good cooperation between strength and plasticity and toughness for the cast-rolling fabricated bearing ring can be obtained in this study.