Figure 4 - available via license: CC BY
Content may be subject to copyright.
Source publication
The constitutive equation of mechanics, namely the stress–strain model of the material, is used to describe the mathematical expression of the mechanical properties of the material (stress–strain–intensity–time relationship). In the cutting simulation of metals, the material constitutive model needs to be established. To study the cutting mechanism...
Contexts in source publication
Context 1
... stress-strain curves obtained by the SHPB tests are shown in Figure 4. Figure 4a shows the curves with strain rate 5000 S −1 under the different temperatures, and Figure 4b the curves at 600 °C under the different strain rates. ...
Context 2
... stress-strain curves obtained by the SHPB tests are shown in Figure 4. Figure 4a shows the curves with strain rate 5000 S −1 under the different temperatures, and Figure 4b the curves at 600 °C under the different strain rates. Figure 4a confirms that the strength of gray cast iron decreased with the increasing of the temperature. ...
Context 3
... stress-strain curves obtained by the SHPB tests are shown in Figure 4. Figure 4a shows the curves with strain rate 5000 S −1 under the different temperatures, and Figure 4b the curves at 600 °C under the different strain rates. Figure 4a confirms that the strength of gray cast iron decreased with the increasing of the temperature. ...
Context 4
... stress-strain curves obtained by the SHPB tests are shown in Figure 4. Figure 4a shows the curves with strain rate 5000 S −1 under the different temperatures, and Figure 4b the curves at 600 °C under the different strain rates. Figure 4a confirms that the strength of gray cast iron decreased with the increasing of the temperature. Figure 4b shows that the strength of cast iron increased with the increasing of the temperature. ...
Similar publications
Thermoplastic polyurethanes (TPU) have become preferred materials for demanding high strain rate applications in many industries throughout past years. Due to their comparatively high abrasion resistance and toughness, TPU materials form an excellent fit for critical components sustaining high pressures in combination with harsh ambient conditions....
Citations
... In order to illustrate the most current developments in the uses of FEM techniques in CNC machining processes, numerical approaches for the modelling of chip production are examined [81]. To accelerate material removal rate during machining operations, a boundary condition for chip production in the cutting process of grey cast iron utilizing fem technique is created [82]. As a consequence, chip morphologies, mechanisms of chip generation, prediction of chip shape and material removal rates during machining operations of different workpiece materials and machining strategies can be accurately precited and analyzed using FEM simulation. ...
To increase accuracy as well as productivity in CNC machine tools, Finite Element Method (FEM) are applied to the machining operations and machine tool structures. As a result, the errors of machining operations can be analyzed and minimized in order to enhance accuracy of machined parts. Also, by analyzing the stress and deformations of the machine tool elements under actual loads, performances as well as working life of the machine tool structures can be enhanced. The study reviews the analysis and modification of CNC machine tool operations and structures using finite element methods from the recent published papers. Applications of the FEM methods in the simulation of cutting temperatures, cutting forces and energy consumption, chip formation, deflection and deformation errors of thin-walled components, and tool wear rate during machining processes are reviewed to demonstrate the capabilities of the FEM simulation in CNC machining modification. Furthermore, applications of the FEM to mod el various machine tool components such as the bed, ball screw, spindle, and guideways are studied in order to enhance the performances of various machine tool elements such as mechanical properties in real-world working situations. In order to fill the gaps between the existing studies and published papers, innovative concepts and approaches of future research works are also suggested. Thus, the research field can be developed by reviewing and analyzing previous achievements in published research works in order to offer innovative concepts and approaches in applications of FEM techniques in modifying machining procedures and CNC machine tool structures.
... With the increase in temperature, the occurrence of adhesion can be tangible. Tu and Shi (2019) have believed that the energy, stored in the cutting process, is basically changed into cutting heat, and hence, leads to increasing the temperature of the tool and workpiece, as well. The high roughness values (Rz and Ra) of the HJ sample can be related to this phenomenon. ...
The objective of the present study is to investigate the effect of chemical composition and microstructure on machinability, mechanical properties, and crack growth of GG-20 gray cast iron for brake drum application. The effects of a reduction in C and Si on microstructural parameters such as type, size, and aspect ratio of graphite particles, interlamellar spacing of pearlite, and the presence of MnS were investigated. In the following, the effect of different microstructures on mechanical properties and machinability of cast iron were studied. The fracture surface, crack growth, worn surface, chip formation and wear on cutting tools have been studied as well. The results showed that both tensile strength and hardness increased, and the machinability reduced by decreasing C and Si. By reducing the C content from 3.4% to 3.2%, the maximum hardness value and tensile strength were obtained to be 207HB and 286 MPa, respectively. Moreover, the Ra and Rz values were increased to 4.3 μm and 25.8 μm, respectively. With an increase in the length of graphite flakes, the distance between microcracks on the machined chips decreased. In the sample with the lower hardness value, delamination occurred extensively and led to the disappearance of cracks and pores on the worn surface.
... Some studies recommend using polycrystalline cubic boron nitride (pcBN) for highspeed processing of cast iron [13][14][15], but this cannot be applied in the case of the trimming dies used to clean anode supports. In addition, in addition to the possibility of conducting experimental research on cast iron cutting processes, cutting simulation methods can be applied, such as the finite element method (FEM), which allows us to obtain information on the process of splinter formation, distribution voltages, temperature distribution [16][17][18][19]. ...
Increasing the durability of trimming dies used to clean anodes is a very important goal in order to reduce the costs involved in obtaining aluminum. The research focused both on choosing an optimal material for the execution of trimming dies and on the application of technologies for plating active areas and, at the same time, on optimizing the geometric shape of the active area of the trimming die. In order to choose an optimal material from which to make the trimming dies, it was taken into account that they are usually made of X210Cr12 steel. In the stage of choosing an optimal material for the execution of the trimming dies, five steels were taken into account, namely: K105, K107, K110, K360, and K460. Analyses of the metallographic structure of the passage area were performed between the metal deposited by welding and the base material, demonstrating the fact that hot welding plating allows obtaining a more homogeneous metallographic structure compared to cold welding plating. The choice of new material was not a solution to increase the durability of the trimming die. Change in the trimming die geometry determined a reduction in deformations of about 13.8 times and of the equivalent stresses of about 7 times compared to those obtained in the case of the old trimming die. In addition, the durability of the trimming die with the new construction shape increases approximately three times compared to the trimming die with the old geometric shape. This demonstrates that the solution to increasing the durability of the trimming die is to adopt an optimal geometry of the active part at the expense of choosing an optimal material.
This article is devoted to modeling the temperature distribution along the rake surface of the lathe cutter for a given moment in the evolution of the cutting system. The approach was based on the application of hydrodynamic analogies to the evaluation of deformation processes in the processed material and combined data of a full-scale and digital experiment. Digital modeling of contact processes was carried out by the determination of the geometric parameters of the plastically deformed layer by the finite element method. Part of the initial data for computer modeling and subsequent verification of its results was carried out on the basis of a full-scale experiment data with longitudinal turning of stainless steel 12H18N9T work piece using a cemented carbide insert T15K6. By means of a digital experiment the boundaries of the zone of secondary plastic deformations in the chips were determined, then a temperature distribution curve was constructed on the rake surface of the cutter in two versions: for variable and for a constant average thickness of the deformed layer. It was found that the average value of the contact temperature in both cases differs slightly and agrees well with the results of the full-scale experiment. The difference between the maximum temperature values was significant in case of variable layer thickness, the temperature value was 11% lower than for the variant with a constant value of this parameter.KeywordsCutting zoneTemperature valueStainless steelLongitudinal turningPlastic deformations
The application of finite element models is a promising method for ensuring part quality during machining to accurately predict induced residual stresses and cutting forces. The present study applied Analysis System software to formulate a 3D model to predict induced residual stress and forces for AISI 1020 alloy. Taguchi method was applied in the design of the experiment with three levels and three factors selected: Cutting speed, feed rate and depth of cut. For validation, stresses are measured using an x‐ray diffractometer from the surface to a depth of 0.6 mm in steps of 0.2 mm. The cutting forces are determined using a force dynamometer. Simulation results showed that cutting speed, feed rate and depth of cut contributed 94.76 %, 0.048 %, and 0.11 % respectively. The predictive model equations were statistically significant with a p‐value of <0.005. The average induced residual stress on the superficial layer from the experiment and simulation were −367.7 MPa and −365.6 MPa respectively. The average residual stresses obtained at depths of 0.2 mm, 0.4 mm, and 0.6 mm were −260 MPa, −233 MPa, and −211 MPa, respectively. The proposed model offers a potential solution to reducing the costs of experimental methods.
Grey cast iron (GCI) is the most common metal casting product in the world. Therefore, achieving sustainable production for this particular material will provide a significant impact on the sustainability issue of metal industries in general. This paper attempts to enhance the sustainability of grey cast iron turning through a high speed, dry turning process. The effect of cutting parameters on three assessments of product sustainability index (PSI) called energy consumption (EC), tool cost (TC), and surface roughness (SR) was investigated using the Taguchi method. The analysis of the signal to noise (S/N) ratio shows that the minimum depth of cut (0.1 mm) gives the optimal performance for all three assessments. Meanwhile, the cutting speed and feed rate reveal a conflict in obtaining the best performance. To help with making a decision, a Taguchi-based Bayesian optimization method was proposed and the capability of the method on suppressing the number of samples to obtain the optimum cutting parameters was demonstrated. Furthermore, the reasons for the optimum cutting condition were also presented.
