Papers by Keyword: Cutting Temperature

Abstract: This article considers the method of determining the parameters of the rheological properties of material of titanium alloy BT6 used in aircraft engine technology, under face milling. Calculations were carried out in CAE system Deform using FEM - model.

Abstract: In machining operation, the quality of surface finish is an important requirement for many turned work pieces. cutting temperature is one of the most important parameters in determining the cutting performance and tool life. the objective for this work is to estimate the cutting temperature in 3D model on tool-chip interface and the interface temperature during turning process, using the digital simulation software COMSOL Multiphysics.The tool–chip interface temperature results obtained from experimental results by using C45 medium carbon steel work piece with natural contact tools, without the application of cooling and lubricating agents and a K type thermocouple technique was used for estimating cutting temperatures in a turning operation.This procedure facilitates the determination of the temperature at tool-chip interface in dry turning process, which is still a challenge for existing experimental and numerical methods.

Abstract: Bone drilling commonly exists in clinical practice and the heat and force generated by the drilling process has a huge impact on the surgery effect and the recovery of patients. High speed drilling, proved to have less injury and be more efficient when compared to the traditional low speed drilling, is considered to be the development direction of bone drilling-related surgeries. In order to make a further study of the controlling of the heat and force during the bone drilling process, the experiment designed to examine the influence of the diamond coating has been conducted and the result indicates that the diamond coating generally has little influence on the drilling force, however, it can increase the drilling temperature to a certain extent which indicates that the diamond coating is not suitable to apply to bone drills under the conditions of the conducted experiments. The result of this research could be of some help to the development of new kinds of medical drills.

Abstract: Cutting force and temperature are the two chief factors affecting bone rehabilitation during bone cutting in many orthopedic surgeries. To reveal new knowledge of thermal and force when milling cortical bone, slotting experiments were carried on high-speed milling platform. Cutting force and temperature were measured during the milling process. The effects of cutting inputs on cutting thermal and force were researched in detail. The results showed that: feed rate and spindle speed had a great impact on the milling temperature, while the milling force was mainly influenced by spindle speed. A feed rate of 1.0-1.4 mm/s is recommended to obtain preferable milling force and temperature, and a larger feed rate of 1.2-1.4 mm/s is advised to use with a lower spindle speed (8000-20000 r/min), while a smaller feed rate of 1.0-1.2 mm/s should be chosen when spindle speed was between 20000-40000 r/min. Feeding parallel to the growth direction of the cortical bone can significantly reduce the milling temperature, but there was no obvious change in milling force. The lowest cutting temperature obtained during the experiment was around 50 °C without coolant, which was acceptable for orthopedic surgeries.

Abstract: This work examined improvements in cutting efficiency obtained during the slicing of sapphire workpieces when adding CeO₂ to the cutting fluid. Various machining parameters, including the cutting temperature, machining surface tolerance, surface quality and tool wear, were assessed. It was confirmed that both the cutting temperature and the machining surface tolerance are reduced by the presence of CeO₂ in the cutting fluid. Observations of the machined surfaces and the cutting tool also demonstrated that both brittle fracturing of the surface and loss of abrasive grains were suppressed following the addition of CeO₂. These results suggest that the cutting temperature likely affects the accuracy of the cutting process and that CeO₂ appears to improve cutting efficiency by reducing the workpiece temperature and by stabilizing the cutting process.

Abstract: In this study, it is discussed how the cutting conditions for drilling deep holes in austenite stainless steel affect the machining accuracy of the hole straightness and the cutting temperature rise. As a result, it is possible to reduce the thrust force and make the machining time short by the combination of the step-feed amount and the feed rate. By changing the drill in incremental step from short drill length to long drill length, the straightness was improved. It was also found that the temperature rise of the drill was around 10 K regardless of the cutting speed when the small step-feed amount of 10 μm was given.

Abstract: Titanium alloy is becoming increasingly employed in the aerospace industries due to its good mechanical and chemical properties. As a typical difficult-to-machine material, there are problems of fast tool wear and poor stability of the processing quality in the machining process. Therefore, experiments of high feed milling of TB2 titanium alloy in liquid nitrogen cooling were carried out to measure the cutting force and the cutting temperature. The experimental results showed that under some parameters, liquid nitrogen could decrease the cutting force and cutting temperature in comparison with dry cutting. What’s more, the tool life as well as the surface quality was improved.

Abstract: Titanium alloy Ti6Al4V has poor machinability, which leads to high unit cutting force and cutting temperature, rapid tool failure. In this study, the effect of the cutting speed, feed rate and cooling condition on cutting force and cutting temperature is critically analysed by turning experiment. At the same time, the relationship is established among tool wear, cutting force and cutting temperature. This investigation has shown that cutting speed is the decisive factor which increasing cutting force and cutting temperature. In the process of turning, tool wear results in high amounts of heat and mechanical stress, which leads to serious tool wear. The Minimal Quantity Lubrication reduces the frictional condition at the chip-tool, decreases cutting force and cutting temperature, and delays the tool failure.

Abstract: In order to get an accurate online measurement for the transient cutting temperature in precision, in an ultra-precision cutting process,a temperature measuring device should be assessed whether it can obtain precise magnitude readings and variables of which are measured accurately. The just produced thin-film thermocouple used to measure tool cutting temperature must be correctly calibrated[3,4] , however traditional calibrating process problems rely on manual operation completely with lots of problems such as low efficiency, high labor intensity and large error. this paper proposes an automatic calibration system for thin-film thermocouple by using temperature measuring furnace, data acquisition card and computer-based software. The system makes an automatically and intelligently calibration process. By using a high-precision data acquisition card and precision amplifier circuit, eight thermocouples can be calibrated at the same time automatically which effectively shortens the calibration time and improves the accuracy. Use temperature metering furnace to control data acquisition. Secondary error from using standard thermocouple and other methods to collect the temperature metering furnace real-time temperature is eliminated. The system software modules consist of data reading, data processing, data display, database operation, data query and report generation module. The experimental results show that nonlinear fitting error is less than 0.6% within the temperature measurement range, which meets the requirement of the secondary precision of thermocouple error. This paper intends to provide a new calibration method for thermocouple temperature measurement tool development and production[7].

Abstract: High-speed milling tests were performed on vol. (5%-8%) TiC_p/TC4 composite in the speed range of 50-250 m/min using PCD tools to nvestigate the cutting temperature and the cutting forces. The results showed that radial depth of cut and cutting speed were the two significant influences that affected the cutting forces based on the Taguchi prediction. Increasing radial depth of cut and feed rate will increase the cutting force while increasing cutting speed will decrease the cutting force. Cutting force increased less than 5% when the reinforcement volume fraction in the composites increased from 0% to 8%. Radial depth of cut was the only significant influence factor on the cutting temperature. Cutting temperature increased with the increasing radial depth of cut, feed rate or cutting speed. The cutting temperature for the titanium composites was 40-90 °C higher than that for the TC4 matrix. However, the cutting temperature decreased by 4% when the reinforcement's volume fraction increased from 5% to 8%.