Hot Deformation Behavior and Processing Map of 40MnBH Alloy Steel

The hot deformation behavior of 301 L stainless steel is investigated at 1000–1250 °C and 0.1–50 s−1. Deformation characteristics are studied through compressive stress–strain curves and constitutive equations. According to the dynamic material model and a series of diffusion annealing experiments, the hot processing map of 301 L stainless steel is established to determine the suitable processing domain. The results show that the stable domain is located in 1085–1240 °C and high strain rate range of 4.5–50 s−1, and the strain rate is the main factor affecting the machinability. Based on the hot compression tests, δ‐ferrite gradually forms a network structure with the increase of temperature; however, it can be inhibited at high strain rate. Therefore, it is necessary to reduce the temperature and increase the strain rate in the actual processing of the machinable area. It is found that diffusion annealing can reduce the content of δ‐ferrite from 12% to 0.67%, and the dissolution of δ‐ferrite is controlled by the diffusion of Cr and Ni, especially noticeable at the interface between γ and δ phase. Finally, the optimum diffusion annealing process parameter is determined at 1300 °C and 10 min.

Section: Introductionmentioning

confidence: 99%

Hot Deformation Behavior of 301L Stainless Steel and Dissolution Behavior of δ‐Ferrite During Heat Treatment

Liu

Wang

et al. 2023

“…A processing map is an effective way to optimize the hot‐working parameters and analyze the mechanisms under different deformation conditions, and the processing map has been widely adopted during the hot‐working processes of a variety of metallic materials. [ 8–14 ] Prasad [ 15 ] first presented a processing map, which can be used to predict and analyze the deformation mechanism of materials and optimize reasonable hot deformation parameters to avoid material defects.…”

Section: Introductionmentioning

confidence: 99%

Study on Flow Behavior and Processing Maps of High‐Ti Low‐C Microalloyed Steel during Hot Compression

Song

Gao

Wang

et al. 2021

Deformation behavior of a high‐Ti low‐C microalloyed steel is studied by isothermal compression tests at temperatures of 800–1100 °C and strain rates of 0.1–10 s−1. The results indicate that the lower the strain rate and higher the temperature of steel, the more likely is the dynamic recrystallization. The stress–strain predicted by the constitutive model, which is established based on the experimental data, are in good agreement with the experimental results. It is noted from the processing maps of steel at various strains that there is instability zone which should be avoided during thermal processing at strain rate less than 1 s−1. The range of 850–1100 °C and 5–10 s−1 strain rate is more conducive to the processing of experimental steel. The movement of grain boundaries, subboundaries, and dislocations is hindered by precipitates in steel. In addition, the mean grain size of austenite at 0.1 s−1 is larger than 5 s−1. This is mainly because low strain rate provides more time for growth of grains.

Hot Deformation Characteristics and Processing Map of 1Cr12Ni2Mo2WVNb Martensitic Stainless Steel

Zhao

Zhang

Yang

et al. 2020

Herein, the hot deformation behavior of 1Cr12Ni2Mo2WVNb martensitic stainless steel is investigated through the high‐temperature thermal compression test. Meanwhile, a strain‐compensated Arrhenius constitutive equation is established. The correlation coefficient R between the predicted value and the experimental value is 0.994, and the average absolute relative error (AARE) (%) value is calculated to be 3.7845%. These results show that the improved constitutive model of 1Cr12Ni2Mo2WVNb steel achieves a higher accuracy in predicting the flow stress value. Moreover, the equation regarding the peak stress (strain), the critical stress (strain), and the Zener–Holomon parameter is constructed, which exhibits good linearity. In addition, the hot processing maps of 1Cr12Ni2Mo2WVNb steel under the strains of 0.3, 0.4, 0.5, and 0.6 are also established, respectively, based on the compression test. According to the processing map and microstructural observation, it is concluded that the optimal processing conditions for 1Cr12Ni2Mo2WVNb steel are determined as follows: a temperature of 1070–1100 °C, a strain rate of 0.8–1 s−1, and a peak power dissipation efficiency of about 0.34.