Contributions of High-Speed Cutting and High Rake Angle to the Cutting Performance of Natural Rubber

2014 ◽  
Vol 8 (4) ◽  
pp. 550-560 ◽  
Author(s):  
Naoki Takahashi ◽  
◽  
Jun Shinozuka
Keyword(s):  
Natural Rubber ◽  
Shear Zone ◽  
High Speed ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Rake Angle ◽  
Cutting Performance ◽  
Machined Surface ◽  
Shape Accuracy ◽  
High Speed Cutting

This study investigates the contributions of high-speed cutting and a high rake angle to the improvement of the cutting performance of natural rubber. Orthogonal cutting experiments were conducted at cutting speeds ranging from 1.0 m/s to 141.1 m/s. The rake angles examined were 0°, 20° and 50°. The following results were obtained from the experiments. The cutting ratio is almost 1.0 regardless of the cutting speed and rake angle. The cutting force rises rapidly as the cutting speed increases. High-speed cutting or a high rake angle eliminates tear defects on the machined surface and reduces chipping defects at the entry edge of the workpiece. An uncut portion, however, always remains at the exit edge. The cross-sectional shape of the machined surface becomes concave. Besides, the machined surface comes into broad contact with the clearance face. These degradations in the shape accuracy arise from the large elastic distortion that occurs in the shear zone. Increasing the cutting speed improves the flatness of the machined surface. Although an analysis of the cutting mechanism reveals that the apparent stiffness of the material in the shear zone is enhanced with increasing the cutting speed, a very high cutting speed worsens the shape accuracy because of the development of shock waves. Depending on the rake angle, there is a critical cutting speed that should not be exceeded to maximize the cutting performance of natural rubber.

Investigation of Surface Characteristics and Chip Morphology in High Speed Cutting of Inconel718 Based on SHPB System

2019 ◽  
Author(s):  
Zengqiang Wang ◽  
Zhanfei Zhang ◽  
Wenhu Wang ◽  
Ruisong Jiang ◽  
Kunyang Lin ◽  
...  
Keyword(s):  
Surface Roughness ◽  
High Speed ◽  
Split Hopkinson Pressure Bar ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Surface Profile ◽  
Chip Morphology ◽  
Depth Of Cut ◽  
Machined Surface ◽  
High Speed Cutting

Abstract High speed cutting (HSC) technology has the characteristics of high material removal rates and high machining precision. In order to study the relationships between chip morphology and machining surface characteristic in high speed cutting of superalloy Inconel718. High-speed orthogonal cutting experiment are carried out by used a high speed cutting device based on split Hopkinson pressure bar (SHPB). The specimen surfaces and collected chips were then detected with optical microscope, scanning electron microscope and three-dimensional surface profile measuring instrument. The results show that within the experimental parameters (cutting speed from 8–16m/s, depth of cut 0.1–0.5mm), the obtained chips are sawtooth chips and periodic micro-ripple appear on the machined surface. With the cutting speed increases, machining surface roughness is decreases from 1.4 to 0.99μm, and the amplitude of periodic ripples also decreases. With the cutting depth increases, the machining surface roughness increases from 0.96 to 5.12μm and surface topography becomes worse. With the increase of cutting speed and depth of cut, the chips are transform from continues sawtooth to sawtooth fragment. By comparing the frequency of surface ripples and sawtooth chips, it is found that they are highly consistent.

scholarly journals Experimental Investigation on the Cutting Mechanism of Oxygen Free Copper in Cutting Speeds Ranging from 1 m/s to 210 m/s

2013 ◽  
Vol 797 ◽  
pp. 208-213 ◽  
Author(s):  
Jun Shinozuka
Keyword(s):  
High Speed ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Shear Plane ◽  
Friction Angle ◽  
Temperature Fields ◽  
Cutting Mechanism ◽  
Machined Surface ◽  
High Speed Cutting

The orthogonal cutting tests of oxygen free copper with a cutting speed of from 1 m/s to 210 m/s were performed. The effect of the high-speed cutting on the improvement over the quality of the machined surface, which was evaluated by the thickness of the plastic flow layer and the surface roughness, was examined. By employing the simple shear plane model, the cutting mechanism was analyzed. The results were compared with the results for cutting of aluminum alloy obtained previously. For oxygen free copper, the resultant cutting force does not increase in high-speed cutting. However, the friction angle on the tool-chip interface rises clearly in high-speed cutting. This paper discusses the reason for the increase in the friction angle at the tool-chip interface by investigating the stress and temperature fields on the shear plane and the tool-chip interface.

Influence of the Process Variables on the Temperature Distribution in AISI 1045 Turning

2012 ◽  
Vol 557-559 ◽  
pp. 1364-1368
Author(s):  
Yong Feng ◽  
Mu Lan Wang ◽  
Bao Sheng Wang ◽  
Jun Ming Hou
Keyword(s):  
Temperature Distribution ◽  
High Speed ◽  
Metal Cutting ◽  
Constitutive Relations ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Fe Model ◽  
Process Variables ◽  
Machined Surface ◽  
Aisi 1045

High-speed metal cutting processes can cause extremely rapid heating of the work material. Temperature on the machined surface is critical for surface integrity and the performance of a precision component. However, the temperature of a machined surface is challenging for in-situ measurement.So, the finite element(FE) method used to analyze the unique nonlinear problems during cutting process. In terms of heat-force coupled problem, the thermo-plastic FE model was proposed to predict the cutting temperature distribution using separated iterative method. Several key techniques such as material constitutive relations, tool-chip interface friction and separation and damage fracture criterion were modeled. Based on the updated Lagrange and arbitrary Lagrangian-Eulerian (ALE) method, the temperature field in high speed orthogonal cutting of carbon steel AISI-1045 were simulated. The simulated results showed good agreement with the experimental results, which validated the precision of the process simulation method. Meanwhile, the influence of the process variables such as cutting speed, cutting depth, etc. on the temperature distribution was investigated.

Calculating of the Temperature Distribution of Primary Shear Zone in Orthogonal High Speed Cutting Based on the Non-Uniform Volume Moving Heat Source

2009 ◽  
Vol 626-627 ◽  
pp. 105-110 ◽  
Author(s):  
Guo He Li ◽  
Min Jie Wang
Keyword(s):  
Temperature Distribution ◽  
Heat Source ◽  
Shear Zone ◽  
High Speed ◽  
Cutting Temperature ◽  
Cutting Speed ◽  
Constitutive Relationship ◽  
Moving Heat Source ◽  
High Speed Cutting ◽  
Strain And Strain Rate

A method was presented for calculating the temperature distribution of primary shear zone in orthogonal high speed cutting based on the non-uniform volume moving heat source. The temperature distribution of primary shear zone in orthogonal high speed cutting was calculated by the dynamic plastic constitutive relationship and the distribution of strain and strain rate of primary shear zone. The results show that the temperature distribution of primary shear zone is uneven, from the original plane to the cutoff plane, the cutting temperature increases continuously. In the middle of primary shear zone, the change of cutting temperature is larger, at the position near to original plant and cutoff plane, the change of cutting temperature is smaller. The cutting temperature increases with the increase of cutting speed and cutting depth, but decreases with the increase of rake angle. The comparison with existing method shows that the method presented in this paper is not only available, but also simple, convenient and more accord with the fact of orthogonal high speed cutting.

Experiment Study of Serrated Chip and Surface Roughness of High Speed Cutting of Ti6Al4V

2014 ◽  
Vol 800-801 ◽  
pp. 571-575
Author(s):  
Guo He Li ◽  
Yu Jun Cai ◽  
Hou Jun Qi
Keyword(s):  
Surface Roughness ◽  
High Speed ◽  
Cutting Speed ◽  
Rake Angle ◽  
Adiabatic Shear ◽  
Cutting Condition ◽  
Experiment Study ◽  
Cutting Depth ◽  
Serrated Chip ◽  
High Speed Cutting

Under the condition of cutting speed 10-300m/min, rake angle -10°、0°、10°and cutting depths 0.05mm、0.1mm and 0.2mm, the experiment study of adiabatic shear serrated chip and surface roughness are carried out. The influence of cutting condition on serrated chip is analyzed through the metallographic observation of obtained chip. By the measurement of finished surface, the influenc of cutting condition and adiabatic shear on surface roughness is also investigated. The rusults show that the reason lead to serrated chip in high speed cutting of Ti6Al4V is adiabatic shear, not the periodic fracture.The adiabatic shear serrated chip is easier appear and the degree of segment is more large under the condition of higher cutting speed, larger cutting depth and smaller rake angle. The surface roughness is smaller when the cutting speed is higher, cutting depth is larger, and rake angle is smaller.

Study on Residual Stress for High-Speed Cutting Titanium Alloy Based on Finite Element Method

2011 ◽  
Vol 188 ◽  
pp. 216-219 ◽  
Author(s):  
M.H. Wang ◽  
Zhong Hai Liu ◽  
Hu Jun Wang
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Titanium Alloy ◽  
High Speed ◽  
Cutting Speed ◽  
Simulation Method ◽  
Residual Tensile Stress ◽  
Cutting Depth ◽  
Machined Surface ◽  
High Speed Cutting

In order to improve machined surface quality and reduce the deformation, the residual stress involved in cutting titanium alloy was studied under different cutting speed and cutting depth by finite element simulation method. The results indicate that the increase of cutting speed and cutting depth are helpful to the surface residual compressive stress generating. However the increase of cutting speed also leads to the increase of surface residual tensile stress, the effect degree is relatively small. It is required to select higher cutting speed and smaller cutting depth to improve the surface stress state and reduce the unexpected distortion.

Investigation for High Speed Ultrasonic Cutting of Aluminum Alloy

2012 ◽  
Vol 516 ◽  
pp. 367-372 ◽  
Author(s):  
Keisuke Hara ◽  
Hiromi Isobe ◽  
Yoshihiro Take ◽  
Toshihiko Koiwa
Keyword(s):  
High Speed ◽  
Cutting Speed ◽  
Cutting Conditions ◽  
Ultrasonic Oscillation ◽  
Workpiece Material ◽  
Machined Surface ◽  
High Speed Cutting ◽  
Cemented Carbide Tool ◽  
Cutting Operation ◽  
Ultrasonic Cutting

This study investigated phenomena of ultrasonic cutting in the case of high-speed conditions. Ultrasonically assisted cutting techniques were developed by Kumabe in the 1950s. He found a critical cutting speed that limits cutting speed to obtain ultrasonically assisted effects and is calculated by frequency and amplitude of oscillation. In general, ultrasonically assisted cutting is not suitable for high-speed cutting conditions because the effects of ultrasonic application are cancelled due to tool contacts with the workpiece during the cutting operation. Present ultrasonically assisted cutting cannot allow increased cutting speed because cutting speed is limited by a critical cutting speed that is less than that compared with general cutting speed. And ultrasonically assisted cutting cannot improve productivity due to long processing time. We conducted high-speed ultrasonic cutting, and the maximum cutting speed in this research was 300 m/min which is higher than general critical cutting speed. The workpiece material was A5056 and cemented carbide tool inserts were employed in this research. Without ultrasonic oscillation, machined surface retained some built up edge and surface roughness is 28 μmRz. In the case of ultrasonic cutting, surface hasnt built up edge and periodically marks due to ultrasonic oscillation remained on the surface. The roughness of conventionally cut surface is better than in ultrasonic cutting. The cutting phenomena of ultrasonic cutting are different compared with those under conventional cutting conditions.

Effect of Boronizing on Cutting Performance of Ti(C,N)-Based Cermet Tool

2013 ◽  
Vol 589-590 ◽  
pp. 390-394
Author(s):  
Hai Dong Yang ◽  
Ju Li Hu ◽  
Yu Ming Zou ◽  
Xiao Yang ◽  
Xiao Jun Liu
Keyword(s):  
High Speed ◽  
Cutting Tool ◽  
Great Influence ◽  
Cutting Speed ◽  
Cutting Performance ◽  
Test Results ◽  
Negative Effects ◽  
High Speed Cutting ◽  
Ceramic Cutting Tool ◽  
Cutting Speeds

Through the experiment of cutting 45 steel, the influence of boronizing on Ti (C,N)-based ceramic cutting performance in different cutting speeds were discussed. The test results indicated that: regardless of boriding, cutting speed has a great influence on the life of Ti (C,N)-based ceramic cutting tool. Within the limit of 200~400 m/min, the lower the cutting speed is, the longer tools life. At the minimum speed, boronizing greatly improves cutting performance and doubles tool life. It has no significant but negative effects once over 300 m/min. The decrease of the abrasion resistance of boronized layer is mainly influenced by the intense thermal shock of high speed cutting.

Control and Mechanism Analysis of Serrated Chip Formation in High Speed Machining of Aluminum Alloy 7050-T7451

2020 ◽  
Vol 990 ◽  
pp. 13-17 ◽  
Author(s):  
Qi Hang Shi ◽  
Zong Cheng Hao ◽  
Shuai Wang ◽  
Xiu Li Fu ◽  
Hui Wang
Keyword(s):  
Aluminum Alloy ◽  
Chip Formation ◽  
High Speed ◽  
Morphological Evolution ◽  
Cutting Speed ◽  
Mechanism Analysis ◽  
Serrated Chip ◽  
Machined Surface ◽  
High Speed Cutting ◽  
Cutting Speeds

Aluminum alloy 7050-T7451 is widely used in aeronautical large structural parts, and high speed cutting is often used in machining. The serrated chip is a critical state for chip formation in high speed cutting, and its formation and control mechanism are of great significance for actual machining. To study the chip formation of high speed cutting aluminum alloy 7050-T7451, the chips at different cutting speeds are obtained by high speed cutting experiments. Combined with microscopic observation, the chip shape evolution, chip localization fracture process and mechanism of different cutting speeds are analyzed. The morphological evolution of chips and the mechanism of chip breaking during high speed cutting of aluminum alloy are revealed. According to the machined surface of the chip root and the angle of the chip, the formation mechanism of the curl radius formed by the chip is analyzed. The critical cutting speed of plastic-brittle transformation of aluminum alloy 7050-T7451 in high speed cutting is obtained by studying the critical condition for strip-to-serration transition of chip morphology.

Wear Performance Evaluation of Tungsten Carbide Taps in Blind Hole Tapping Cast Iron

2010 ◽  
Vol 126-128 ◽  
pp. 755-759 ◽  
Author(s):  
Ming Chen ◽  
Xiao Hui Zhang ◽  
Bing Han ◽  
Bin Rong ◽  
Gang Liu
Keyword(s):  
Cast Iron ◽  
Tungsten Carbide ◽  
High Speed ◽  
Cutting Speed ◽  
High Speed Steel ◽  
Ductile Cast Iron ◽  
Cutting Performance ◽  
Production Lines ◽  
High Speed Cutting ◽  
Ticn Coating

The engineblock and cylinderhead of automobile are usually made of cast iron, and tapping of blind holes is one of the most demanding operations. As usual, tapping is the final process for an engineblock, and the failure of taps can disable the engineblock possibly. The productivity is restricted because of the low cutting speed and poor wear resistance of high speed steel (HSS) taps. Thereby, according to the demand on high speed cutting and low tact time of modern engine production lines, several new typical special tungsten carbide taps are developed and their cutting performance are evaluated in comparison with the commercial taps. In the process of tapping blind holes in gray cast iron and ductile cast iron, several aspects are studied comparatively such as wear mechanism of the first complete and the last incomplete tooth, tap structure, wear of TiCN coating and effects of coolant on cutting performance of taps. This study indicates that straight coated taps with fewer flutes are suitable for high speed tapping of cast iron.

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