The stress-strain curves of TA15 titanium alloy at 750∼950°C and 0.001∼1 s −1 were obtained by hot compression with Gleeble-1500D. Based on the compression experimental data of TA15 titanium alloy, the Johnson-Cook high temperature thermal deformation constitutive equation was established. By calculating the constitutive equation, the flow stress was compared with the measured stress-strain curve, and the accuracy of the equation was verified. Then, based on the theory of hot processing map of dynamic materials, the hot processing map is drawn when the strain is 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6. The reasonable range of hot processing map of TA15 titanium alloy was determined. When the temperature is between 750°C-875°C, the power dissipation factor decreases with increasing strain rate. The maximum power dissipation is distributed between 825°C-950°C. This indicates that recrystallization occurred within this range. The safe zone is mainly concentrated in the temperature range of 885°C-950°C, the strain rate is less than 0.1 s −1 . It can be seen that instability does not occur in the high temperature and low strain region. Therefore, at 885 T 950°C, 0.001  e 0.1 s −1 or 800 T 875°C, 0.001  e 0.002 s −1 , it is reasonable to perform high temperature deformation on TA15 titanium alloy. experiments, optical microscopy (OM), electron backscatter diffraction (EBSD), and quantitative analysis were used to study the β thermal deformation behavior of TA15 titanium alloy. Thermal simulation compression experiments, optical microscope (OM), and electronic backscatter diffraction Technology (EBSD) and Quantitative Analysis Study the β Hot Deformation Behavior of TA15 Titanium Alloy ,analyzed the influence of deformation temperature, strain rate and deformation on its flow stress and microstructure; Xi et al [12]. Studied the evolution of the microstructure of TA15 titanium alloy after superplastic deformation and the effect of deformation conditions on the superplastic deformation behavior; Xu et al [13]. Experimentally studied the compression deformation behavior and microstructure characteristics of TA15 titanium alloy under the conditions of strain rate 0.01∼20 s −1 and deformation temperature 850∼1050°C, TA15 constitutive equation was derived using Arrhenius hyperbolic sine function model. Based on the dynamic material model, the hot processing map of the alloy at the true strain of 0.1∼0.7 was established. The hot processing map is very practical for studying the flow stress of materials and optimizing the parameters of heat treatment, and its practicality has been used in Bstmuf601 superalloy [14], medium and high carbon high silicon bainite steel [15], as-cast 6Mo super austenitic stainless [16], Sa508-Iv steel [17], 34CrNiMo6 steel [18], Fe-Mn-Al-C steel [19] and other materials have been proven.Constitutive model is the key to the relationship between reaction rheological behavior and metal and alloy parameters [20][21][22][23]. Therefore, the flow stress, constitutive equation, hot processing...

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Cross wedge rolling has the advantages of high production efficiency, good product quality, high material utilization, environmental protection, and low cost. It is one of the best processing methods for producing shaft blanks. In this paper, a cross wedge rolling die of TC4 titanium alloy is studied. Based on the Archard wear model, a modified model suitable for cross wedge rolling die wear analysis is derived through finite element simulation. Then, the modified Archard wear model is imported into Deform-3D software for finite element analysis. Orthogonal experimental design is used to combine and analyze different process parameters. Finally, the beetle antennae search (BAS)-genetic algorithm (GA)-back propagation neural network (BPNN) algorithm is used to predict the degree of die wear and to optimize the simulation parameters, which can acquire the process parameters that have the least impact on die wear. The results show that the wear distributions of cross wedge rolling tools is uneven. In general, the most serious areas are basically concentrated in the wedge-shaped inclined plane and rectangular edge lines. The reason is that the tangential force and radial force received by the die are relatively large, which leads to increased wear. Moreover, the temperature change is most severe on the wedge-shaped ridge line. When in contact with the workpiece, the temperature rises sharply, which makes the local temperature rise, the mold hardness decrease, and the wear accelerate. Through response surface method (RSM) analysis, it is concluded that the deformation temperature is the main factor affecting wear depth, followed by the forming angle, and that there is an interaction between the two factors. Finally, the feasibility of the BAS-GA-BP algorithm for optimizing the wear behavior of dies is verified, which provides a new process parameter optimization method for the problem of die wear in the cross wedge rolling process.

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