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

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.

2011 ◽  
Vol 188 ◽  
pp. 578-583 ◽  
Author(s):  
Toshiyuki Obikawa ◽  
Masahiro Anzai ◽  
Tsuneo Egawa ◽  
Norihiko Narutaki ◽  
Kazuhiro Shintani ◽  
...  

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.


1998 ◽  
Vol 120 (1) ◽  
pp. 169-172 ◽  
Author(s):  
G. Sutter ◽  
A. Molinari ◽  
L. Faure ◽  
J. R. Klepaczko ◽  
D. Dudzinski

A new high speed machining experiment is designed to obtain orthogonal cutting in a wide range of cutting speeds from 7 m/s to 100 m/s. Quasi-stationary cutting conditions are obtained. The measurement of the longitudinal cutting force reveals the existence of an optimal cutting speed for which the energy consumption is minimum. The genuine tool-workpiece material interaction can be analyzed with that experimental device.


2012 ◽  
Vol 565 ◽  
pp. 370-375 ◽  
Author(s):  
Jun Shinozuka ◽  
Hidenobu Yachi ◽  
Tappei Higashi ◽  
Masato Sando ◽  
Toshio Maetani ◽  
...  

Orthogonal cutting experiment of powder metallurgy steel was performed in cutting speeds ranging from 1 m/s to 150 m/s. High-speed cutting experiment was carried out with a high-speed impact-cutting tester. This study focuses on the change in the effects of free-cutting of manganese sulfide with cutting speed. The principal force and thrust force were measured. The cross sections of the chip and of the machined surface were observed. Color mapping analysis of the tool-chip contact region on the rake face with EPMA was done. Although the serrated type of chip formed in all experiments, the cutting mechanism was analyzed by employing a shear plane model. This paper discusses how the effect that MnS promotes the ductile fracture and the effect that MnS improves the friction property at the tool-chip interface change as the cutting speed increases.


2017 ◽  
Vol 889 ◽  
pp. 84-89
Author(s):  
Pandithevan Ponnusamy ◽  
Mullapudi Joshi

In high speed machining, to dynamically control the mechanical behaviour of the materials, it is essential to control temperature, stress and strain by appropriate speed, feed and depth of cut. In the present work, to predict the mechanical behaviour of Ti6Al4V and 316L steel bio-materials an explicit dynamic analysis with different cutting speeds was carried out. Orthogonal cutting of 316L steel and Ti6Al4V materials with 720 m/min, 900 m/min and 1200 m/min cutting speeds was performed, and the distribution of stress and temperature was investigated using Jonson-Cook material model. Additionally, the work aimed at determining the effect of cutting speed on work piece temperature, when cutting is carried out continuously. From the investigation, it was found that, while machining Ti6Al4V material, for the increase in cutting speed there was increase in tool-chip interface temperature. Specifically, this could found till the cutting speed 900 m/min. But, there was a decrease in tool-chip interface temperature for the increase in speed from 900 m/min to 1200 m/min. Similarly for 316L steel, the tool-chip interface temperature increased when increasing the cutting speed till 900 m/min. But reduction in temperature from 650 °C to 500 °C for steel and 1028 °C to 990 °C for Ti6Al4V were found, when the cutting speed increased from 900 m/min to 1200 m/min. The study can be used to conclude, at what temperature range the adoption of material with controlled shape and geometry is possible for potential applications like, prosthetic design and surgical instruments prior to fabrications.


2012 ◽  
Vol 557-559 ◽  
pp. 1364-1368
Author(s):  
Yong Feng ◽  
Mu Lan Wang ◽  
Bao Sheng Wang ◽  
Jun Ming Hou

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.


2008 ◽  
Vol 375-376 ◽  
pp. 206-210
Author(s):  
Hui Ping Zhang ◽  
Zhen Jia Li ◽  
Er Liang Liu ◽  
Guo Liang Wei

This paper deals with chip breaking behaviour of 3-D complex groove inserts in machining carbon constructional steel-45 steel at high cutting speeds .Cutting experiments were performed at eleven different cutting speeds. Firstly, the results showed that by increasing cutting speeds, the changes of the critical feedrate and chip breaking scopes at high cutting speeds machining with 3-D complex groove inserts were nonlinear and not monotonous function relations. Then, mathematic models were built. Secondly, the results showed that the critical depth of cut was a constant value at various cutting speeds. And, the curves of the critical depth of cut were perpendicular lines. For this purpose, the critical depth of cut mathematic model has been built. The study above lays a theory and basis for future investigation of the mechanism of chip breaking with 3-D groove insert in high speed machining.


Author(s):  
Justin L. Milner ◽  
Jeffrey A. Beers ◽  
John T. Roth

Machining is a popular and versatile manufacturing process that is widely used in today’s industry when producing metallic parts; however, limited tool life can make this an expensive and time consuming fabrication technique. Consequently, methods that decrease the rate of tool wear and, thus, increase tool longevity are a vital component when improving the efficiency of machining processes. To this end, cryogenically treating cutting tools (especially high-speed steel tooling) is becoming more commonplace since research has shown that the treated tooling exhibits significantly higher wear resistance. At this point, however, the effect of cryogenic treatments on ceramic tooling has not been established. Considering this, the research herein presents a feasibility study on the effectiveness of using cryogenic treatments to enhance the wear resistance of WG-300 whisker-reinforced ceramic cutting inserts. To begin, the effect of the cryogenic treatment on the insert’s hardness is examined. Subsequently, tool wear tests are conducted at various cutting speeds. Through this study, it is shown that cryogenically treating the ceramic inserts decreases the rate of tool wear at each of the cutting speeds that were tested. However, the degree of wear resistance introduced by cryogenically treating the inserts proved to be highly dependent on the cutting speed, with slower speeds exhibiting greater improvements. Thus, based on this initial study, the cryogenic treatment of ceramic tooling appears to produce beneficial results, potentially increasing the overall efficiency of machining processes.


Author(s):  
Zengqiang Wang ◽  
Zhanfei Zhang ◽  
Wenhu Wang ◽  
Ruisong Jiang ◽  
Kunyang Lin ◽  
...  

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.


Author(s):  
Dirk Landgrebe ◽  
Julia Schönherr ◽  
Norbert Pierschel ◽  
Stefan Polster ◽  
Andre Mosel ◽  
...  

In the last decade, press hardening has become a fully established technology in both science and industry for the production of ultra-high-strength structural components, especially in the automotive industry. Beside the improvement of car performance such as safety and lightweight design, the production process is also one focus of trends in technology development in the field of press hardening. This paper presents an overview about alternative approaches for optimized process chains of press hardening, also including pre- and post-processing in addition to the actual forming and quenching process. Investigations on direct contact heating technology show new prospects regarding fast and flexible austenitization of blanks at compact device dimensions. By applying high speed impact cutting (HSIC) for trimming of press hardened parts, an alternative technology is available to substitute the slow and energy-intensive laser trimming in today’s press hardening lines. Combined with stroke-to-stroke control based on measuring of process-relevant parameters, a readjustment of the production line is possible in order to produce each part with individual, optimal process parameters to realize zero defect production of property-graded press hardened components with constant high part quality. Significant research in the field of press hardening was carried out at Fraunhofer Institute for Machine Tools and Forming Technology IWU, in the hot forming model process chain which enables the running of experiments under conditions similar to industrial scales. All practical tests were prepared by design of experiments and assisted by thermo-mechanical FE simulations.


2004 ◽  
Vol 126 (6) ◽  
pp. 931-936 ◽  
Author(s):  
N. Ranc ◽  
V. Pina ◽  
G. Sutter ◽  
S. Philippon

The working processes of metallic materials at high strain rate like forging, stamping and machining often induce high temperatures that are difficult to quantify precisely. In this work we, developed a high-speed broad band visible pyrometer using an intensified CCD camera (spectral range: 0.4 μm–0.9 μm). The advantage of the visible pyrometry technique is to limit the temperature error due to the uncertainties on the emissivity value and to have a good spatial resolution (3.6 μm) and a large observation area. This pyrometer was validated in the case of high speed machining and more precisely in the orthogonal cutting of a low carbon steel XC18. The cutting speed varies between 22 ms−1 and 60 ms−1. The experimental device allows one to visualize the evolution of the temperature field in the chip according to the cutting speed. The maximum temperature in the chip can reach 730°C and minimal temperature which can be detected is around 550°C.


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