Fracture Prediction of 304 Stainless Steel Bar with Continuous Rotary Bending Low-stress Precision Cropping

doi:10.3901/JME.2024.01.190

Abstract

Abstract: Low-stress blanking near-net forming method is a new technology for manufacturing shaft parts blank, which has the characteristics of low energy consumption, high cropping efficiency and high cross-section accuracy. However, its cropping mechanism has always been unclear, and it is difficult to obtain ideal cropping process parameters. Therefore, the prediction fracture model, which is the fracture strength factor, is proposed based on cumulative damage theory. Taking 304 stainless steel as the research object, the fracture strength factor is coupled to the finite element model of continuous rotary bending low-stress cropping to predict the fracture. Through the continuous rotary bending low-stress cropping tests, relying on the comprehensive evaluation index of section flatness and cropping time, the correctness of the numerical simulation of continuous rotary bending low-stress cropping fracture prediction based on the fracture strength factor is verified. The results show that the fracture position simulated by fracture prediction model based on the fracture intensity factor is located at the root of annular V notch, which is consistent with the result of cropping separation. The section flatness and cropping time decrease with the increase of loading position. When the loading position is L₁=5 mm and L₂=10 mm, high-efficiency and precise cropping of bar can be realized. Based on the theory of fracture intensity factor, the fracture mechanism of continuous rotary bending low-stress cropping is established, which lays a theoretical foundation for realizing the industrialization of low-stress cropping.

Key words: fracture strength factor, low-stress cropping, numerical simulation, fracture prediction, 304 stainless steel

CLC Number:

TG316

YU Zhengyang, ZHONG Bin, ZHANG Chuanwei, ZHAO Shengdun. Fracture Prediction of 304 Stainless Steel Bar with Continuous Rotary Bending Low-stress Precision Cropping[J]. Journal of Mechanical Engineering, 2024, 60(1): 190-197.

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