Advances on the deformation mechanism and forgingtechnology of 300M high-strength steel heavy componentsin the whole forging process

High-strength steel heavy components are the key load-bearing components of advanced equipment in the defense industry and the national economy, and their quality is directly related to the performance and service safety of advanced equipment. Due to the large size, complex shape of high-strength steel heavy components and multiple deformation passes during the forging process, there are numerous and complex softening mechanisms, the significant difference in temperature distribution, and challenges in the regulation of the flow behavior. These factors make it difficult to regulate the shape and properties of heavy components during the forging process. Therefore, it is necessary to research the deformation mechanism and forging technology of high-strength steel heavy components in the forging process. This paper reviews the advances on the deformation mechanism and forging technology in the whole forging process of high-strength steel heavy components, conducted by the cooperation of our team and China National Erzhong Group Deyang Wanhang Die Forging Co., Ltd. (hereinafter referred to as “Erzhong Wanhang”). In terms of deformation mechanism, the microstructure evolution mechanism and macro/micro modeling and simulation during the whole forging process of high-strength steel heavy components are discussed. In terms of forging technology, the evaluation method for hot workability, the joint optimization design method for blank and pre-forgings, and local regulation of temperature and flow behavior are discussed. In terms of application, based on the above theoretical guidance and technical support, the successful development of landing gear outer cylinder and piston rod forgings of different aircraft types by Erzhong Wanhang is introduced. The difficulties in the integral die forging technology of heavy key components are broken through. Finally, the forging mechanism and technology of heavy key component are summarized and prospected.