scholarly journals Machinability of SMART Forging Process Materials in Intermittent Cutting: 2nd Report : Machinability in Normal Cutting Region and Selection of Optimum Cutting Condition

2019 ◽  
Vol 95 ◽  
pp. 01001
Author(s):  
Mitsuaki Murata ◽  
Makoto Hino ◽  
Ryoichi Kuwano ◽  
Syuhei Kurokawa
Keyword(s):  
High Speed ◽  
Combustion Engine ◽  
Hot Forging ◽  
Cutting Speed ◽  
Maximum Speed ◽  
Cutting Condition ◽  
High Speed Cutting ◽  
Cutting Experiments ◽  
Intermittent Cutting ◽  
Selection Of

Transmission used in automobiles is indispensable from the viewpoint of improvement of maximum speed, quietness and fuel consumption even if the power source of automobile is changed from internal combustion engine to electric motor in the future. We are studying a heat treatment process for imparting machinability to the forged material after hot forging used for a transmission of automobiles. In the past, the heat stored in the material after hot forging was merely released into the atmosphere. We succeeded in imparting machinability to the material by cooling while well controlling the heat stored in the forged material after hot forging. In the previous paper [1], we reported the progress of tool wear of this forged material in the high-speed cutting region with the cutting speed of 200 m/min or more in intermittent cutting. In this report, we conducted cutting experiments on the machinability of this developed forged material in the normal cutting speed region with the cutting speed less than 200 m/min. As a result, at the cutting speed V of V=157 m/min or less, it reached the conclusion that the built-up edges frequently occurred and the tool was chipped due to it. From the previous report and the results of this experiment, it was found that the cutting speed V of about V=213 m/min is optimum for cutting these forged materials with cemented carbide.

Effects of Cooling Conditions on Thermal Crack Initiation of Brittle Cutting Tools during Intermittent Cutting

2015 ◽  
Vol 656-657 ◽  
pp. 237-242
Author(s):  
Kenji Yamaguchi ◽  
Tsuyoshi Fujita ◽  
Yasuo Kondo ◽  
Satoshi Sakamoto ◽  
Mitsugu Yamaguchi ◽  
...  
Keyword(s):  
Crack Initiation ◽  
Thermal Shock ◽  
High Speed ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Condition ◽  
Thermal Crack ◽  
Cooling Conditions ◽  
Cutting Operation ◽  
Intermittent Cutting

It is well known that a series of cracks running perpendicular to the cutting edge are sometimes formed on the rake face of brittle cutting tools during intermittent cutting. The cutting tool is exposed to elevated temperatures during the periods of cutting and is cooled quickly during noncutting times. It has been suggested that repeated thermal shocks to the tool during intermittent cutting generate thermal fatigue and result in the observed thermal cracks. Recently, a high speed machining technique has attracted attention. The tool temperature during the period of cutting corresponds to the cutting speed. In addition, the cooling and lubricating conditions affect the tool temperature during noncutting times. The thermal shock applied to the tool increases with increasing cutting speed and cooling conditions. Therefore, to achieve high-speed cutting, the evaluation of the thermal shock and thermal crack resistance of the cutting tool is important. In this study, as a basis for improving the thermal shock resistance of brittle cutting tools during high-speed intermittent cutting from the viewpoint of cutting conditions, we focused on the cooling conditions of the cutting operation. An experimental study was conducted to examine the effects of noncutting time on thermal crack initiation. Thermal crack initiation was found to be restrained by reducing the noncutting time. In the turning experiments, when the noncutting time was less than 10 ms, thermal crack initiation was remarkably decreased even for a cutting speed of 500 m/min. In the milling operation, the number of cutting cycles before thermal crack initiation decreased with increasing cutting speed under conditions where the cutting speed was less than 500 m/min. However, when the cutting speed was greater than 600 m/min, thermal crack initiation was restrained. We applied the minimal quantity lubrication (MQL) coolant supply to the intermittent cutting operation. The experimental results showed that the MQL diminished tool wear compared with that under the dry cutting condition and inhibited thermal crack initiation compared with that under the wet cutting condition.

High-Speed Capturing of Stress Distribution of Workpiece under Ultrasonically Assisted Cutting Condition

2014 ◽  
Vol 1017 ◽  
pp. 747-752
Author(s):  
Hiromi Isobe ◽  
Keisuke Hara
Keyword(s):  
Stress Distribution ◽  
Cutting Force ◽  
High Speed ◽  
Cutting Tool ◽  
Light Emission ◽  
Cutting Speed ◽  
Cutting Condition ◽  
Photoelastic Method ◽  
Intermittent Cutting ◽  
Ultrasonic Vibration Cutting

This paper reports the stress distribution inside the workpiece under ultrasonic vibration cutting (UVC) condition. Many researchers have reported the improvement of tool wear, burr generation and surface integrity by reduction of time-averaged cutting force under UVC condition. However general dynamometers have an insufficient frequency band to observe the processing phenomena caused by UVC. In this paper, stress distribution inside the workpiece during UVC was observed by combining the flash light emission synchronized with ultrasonically vibrating cutting tool and the photoelastic method. Instantaneous stress distribution during UVC condition was observed. Because UVC induced an intermittent cutting condition, the stress distribution changed periodically and disappeared when the tool leaved from the workpiece. It was found that instantaneous maximum cutting force during UVC condition was smaller than quasi-static cutting force during conventional cutting when the cutting speed was less than 500 mm/min.

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.

Ultra High-Speed Cutting Experiment under the Cutting Condition that Cutting Speed Exceeds Plastic Wave Speed of Workpiece

2011 ◽  
Vol 325 ◽  
pp. 327-332 ◽  
Author(s):  
Jun Shinozuka ◽  
Masato Sando ◽  
Tasuku Horie
Keyword(s):  
Shock Wave ◽  
Shear Zone ◽  
High Speed ◽  
Cutting Speed ◽  
Experimental Result ◽  
Cutting Condition ◽  
Plastic Wave ◽  
High Speed Cutting ◽  
Ultra High Speed ◽  
Impact Cutting

Raising a cutting speed to above speed of a plastic wave of a workpiece material induces the high levels of the hydrostatic stresses in the shear zone, because a plastic wave traveling there becomes a shock wave. In order to ascertain the cutting phenomena occurring under the ultra high-speed cutting condition, the cutting experiments of a pure lead with cutting speeds of up to 140 m/s are performed with a high-speed impact cutting tester developed. The experimental result reveals that the cutting mechanism, especially chip formation, changes remarkably and the friction angle at the tool-chip interface rises in the ultra high-speed cutting. It can be explained that these phenomena arise from the plastic shock wave in the shear zone.

The Application of FEA in High-Speed Cutting

2011 ◽  
Vol 287-290 ◽  
pp. 104-107
Author(s):  
Lian Qing Ji ◽  
Kun Liu
Keyword(s):  
High Speed ◽  
Feeding Rate ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Material Model ◽  
Friction Model ◽  
Cutting Depth ◽  
High Speed Cutting ◽  
Key Technologies

The history and application of the FEA are briefly presented in this paper. Several key technologies such as the building of material model, the establishment of the chip - tool friction model as well as meshing are described. Taking the high-speed cutting of titanium alloy (Ti - 10V - 2Fe - 3Al) as an example , reasonable cutting tools and cutting parameters are determinted by simulating the influences of cutting speed, cutting depth and feeding rate on the cutting parameters using FEA.

High-Speed End Milling Using a Feedforward Control Architecture

1996 ◽  
Vol 118 (2) ◽  
pp. 178-187 ◽  
Author(s):  
E. D. Tung ◽  
M. Tomizuka ◽  
Y. Urushisaki
Keyword(s):  
High Speed ◽  
Feedforward Control ◽  
End Milling ◽  
Phase Error ◽  
Cutting Speed ◽  
Frequency Domain Analysis ◽  
Maximum Speed ◽  
Drive Control ◽  
Machining Errors ◽  
Feedforward Controller

Experiments are performed for end milling aluminum at 15,000 RPM spindle speed (1,508 m/min cutting speed) and up to 3 m/min table feedrate using an experimental machine tool control system. A digital feedforward controller for feed drive control incorporates the Zero Phase Error Tracking Controller (ZPETC) and feedforward friction compensation. The controller achieves near-perfect (±3 μm) tracking over a 26 mm trajectory with a maximum speed of 2 m/min. The maximum contouring error for a 26 mm diameter circle at this speed is less than 4 μm. Tracking and contouring experiments are conducted for table feedrates as high as 10 m/min. Frequency domain analysis demonstrates that the feedforward controller achieves a bandwidth of 10 Hz without phase distortion. In a direct comparison of accuracy, the machining errors in specimens produced by the experimental controller were up to 20 times smaller than the errors in specimens machined by an industrial CNC.

Cutting Experiments in Cutting Speeds of up to 200 m/s with a High-Speed Impact Cutting Tester

2012 ◽  
Vol 523-524 ◽  
pp. 1041-1046 ◽  
Author(s):  
Tappei Higashi ◽  
Masato Sando ◽  
Jun Shinozuka
Keyword(s):  
High Speed ◽  
Ambient Pressure ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
High Speed Impact ◽  
Air Gun ◽  
Impact Cutting ◽  
Compressed Gas ◽  
Cutting Experiments ◽  
Cutting Speeds

High-speed orthogonal cutting experiments with cutting speeds of up to 200 m/s with a high-speed impact cutting tester of air-gun type are attempted. In this tester, a light projectile with a small built-in cutting tool is loaded into a tube, being accelerated by a compressed gas. The projectile captures the chip that is indispensable to analyze the cutting mechanism. The projectile holding the chip is decelerated by another compressed gas just after finishing the cutting, being stopped without damage in the tube. Successful experiment can be accomplished by setting adequate values of the operation parameters for the experiment, which are the pressure of each gas and the opening and shutting time of the solenoid-controlled valve for each compressed gas. In order to determine the adequate values of these parameters, a ballistic simulator that simulates the velocity and position of the projectile traveling in the tube is developed. By setting the values of these parameters obtained by the simulator, the cutting speed of 200 m/s is achieved when the ambient pressure is set to be a vacuum and helium is used for each compressed gas. This paper describes the ballistic simulator developed and shows the experimental results of the high-speed cutting of aluminum alloy A2017.

Multi-criteria optimization and predictive modeling of turning forces in high-speed machining of yttria based zirconia toughened alumina insert using desirability function approach

2015 ◽  
Vol 231 (8) ◽  
pp. 1396-1408 ◽  
Author(s):  
Nilrudra Mandal ◽  
B Doloi ◽  
Biswanath Mondal ◽  
BK Singh
Keyword(s):  
Feed Rate ◽  
High Speed ◽  
Desirability Function ◽  
Cutting Speed ◽  
Depth Of Cut ◽  
Cutting Condition ◽  
Machining Forces ◽  
Feed Force ◽  
Response Optimization ◽  
Zirconia Toughened Alumina

An attempt has been made to apply the Taguchi parameter design method and multi-response optimization using desirability analysis for optimizing the cutting conditions (cutting speed, feed rate and depth of cut) on machining forces while finish turning of AISI 4340 steel using developed yttria based zirconia toughened alumina inserts. These zirconia toughened alumina inserts were prepared through wet chemical co-precipitation route followed by powder metallurgy process. The L9 (4) orthogonal array of the Taguchi experiment is selected for three major parameters, and based on the mean response and signal-to-noise ratio of measured machining forces, the optimal cutting condition arrived for feed force is A1, B1 and C3 (cutting speed: 150 m/min, depth of cut: 0.5 mm and feed rate: 0.28 mm/rev) and for thrust and cutting forces is A3, B1 and C1 (cutting speed: 350 m/min, depth of cut: 0.5 mm and feed rate: 0.18 mm/rev) considering the smaller-the-better approach. Multi-response optimization using desirability function has been applied to minimize each response, that is, machining forces, simultaneously by setting a goal of highest cutting speed and feed rate criteria. From this study, it can be concluded that the optimum parameters can be set at cutting speed of 350 m/min, depth of cut of 0.5 mm and feed rate of 0.25 mm/rev for minimizing the forces with 78% desirability level.

High Speed Machining: A Review from a Viewpoint of Chip Formation

2011 ◽  
Vol 188 ◽  
pp. 578-583 ◽  
Author(s):  
Toshiyuki Obikawa ◽  
Masahiro Anzai ◽  
Tsuneo Egawa ◽  
Norihiko Narutaki ◽  
Kazuhiro Shintani ◽  
...  
Keyword(s):  
Tool Wear ◽  
Life Span ◽  
High Speed ◽  
Cutting Speed ◽  
Strong Nonlinearity ◽  
High Speed Machining ◽  
Cast Irons ◽  
Sliding Test ◽  
Cutting Experiments ◽  
Cutting Speeds

This paper describes strong nonlinearity in log V-log L relationship, which is often found in machining of supperalloys, titanium alloys, hardened steels, cast irons, etc. The nonlinearity plays an important and favorable role in extension of life-span cutting distance at higher cutting speeds; that is, in a certain range of cutting speed, life-span cutting distance increases with cutting speed. Results of tool wear in a sliding test and cutting experiments, which showed the evidences of strong nonlinearity, were investigated and the mechanisms causing the nonlinearity were discussed.

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.

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