scholarly journals Pengaruh Penggunaan Cairan Pendingin (Coolant) terhadap Keausan Pahat Bubut HSS

2020 ◽  
Vol 11 (3) ◽  
pp. 467-475
Author(s):  
Sri Widiyawati ◽  
◽  
Oyong Novareza ◽  
Dwi Hadi Sulistyarini ◽  
Wisnu Wijayanto Putro

Lathe Machine can use for several kinds of the process such as turning, drilling, boring, tapering, and threading. The lathe machine process requires some interaction between processing material with the chisel. Time processing that reaches the worn-out limit is likely called chisel life. One of the factors that affected chisel worn-out is the use of coolant. Therefore researched the effect of one of the variable process that is coolant to HSS Carbide worn-out chisel to predict the lifetime of it. This research was conducted three times without using a coolant, using a coolant ratio of 1:30, and using a coolant ratio of 1:40. The spindle speed of the lathe used is 400 rpm. The tool wear was analyzed through measurement with callipers and the help of CorelDraw X7 software. Based on the measurements made, the results showed that the highest tool wear was found in HSS chisels with 1:40 coolant application, which was a reduction of 1.4 mm.

Author(s):  
D. S. Sai Ravi Kiran ◽  
Alavilli Sai Apparao ◽  
Vempala GowriSankar ◽  
Shaik Faheem ◽  
Sheik Abdul Mateen ◽  
...  

This paper investigates the machinability characteristics of end milling operation to yield minimum tool wear with the maximum material removal rate using RSM. Twenty-seven experimental runs based on Box-Behnken Design of Response Surface Methodology (RSM) were performed by varying the parameters of spindle speed, feed and depth of cut in different weight percentage of reinforcements such as Silicon Carbide (SiC-5%, 10%,15%) and Alumina (Al2O3-5%) in alluminium 7075 metal matrix. Grey relational analysis was used to solve the multi-response optimization problem by changing the weightages for different responses as per the process requirements of quality or productivity. Optimal parameter settings obtained were verified through confirmatory experiments. Analysis of variance was performed to obtain the contribution of each parameter on the machinability characteristics. The result shows that spindle speed and weight percentage of SiC are the most significant factors which affect the machinability characteristics of hybrid composites. An appropriate selection of the input parameters such as spindle speed of 1000 rpm, feed of 0.02 mm/rev, depth of cut of 1 mm and 5% of SiC produce best tool wear outcome and a spindle speed of 1838 rpm, feed of 0.04 mm/rev, depth of cut of 1.81 mm and 6.81 % of SiC for material removal rate.


2013 ◽  
Vol 634-638 ◽  
pp. 2894-2898 ◽  
Author(s):  
M Moayedfar ◽  
Zulkiflle Leman ◽  
H Mirabi ◽  
B.T.H.T. Baharuddin

The effect of forming parameters during the incremental sheet forming process (ISF) was studied for a circular shape sheet part. ISF is known as a rapid prototyping method to pro-duce sheet metal parts in a batch production series. ISF has found to be useful and advantageous which increases its application in industry. A CNC lathe machine was used in this study because it was easily programmed to move an indenter which worked as the tool, through the sheet metal which was clamped on a plain rounded mold. The work also investigated the influence of some process variables such as spindle speed, tool material; tool feed rate and temperature during the forming procedure. The results showed that a proper spindle speed and tool feed rate at some stage in the forming process improved the surface quality and the rate of penetration.


2011 ◽  
Vol 496 ◽  
pp. 259-265 ◽  
Author(s):  
Li Juan Zheng ◽  
Cheng Yong Wang ◽  
Yun Peng Qu ◽  
Li Peng Yang ◽  
Yue Xian Song

This work is focused on the investigation of the influence of the materials of PCB, feed rate, spindle speed and tool wear on thrust force when drilling PCB using 0.3 mm diameter cemented tungsten carbide drills. The results indicate that thrust force increases with feed rate and drill wear, but decreases with spindle speed firstly and then increases with it within the cutting range tested. Thrust force caused by the copper foil is much larger than that caused by the epoxy glass fiber cloth when feed rate is low. However, the difference between them decreases as feed rate increases. The thickness of nail head increases with thrust force. The accuracy of hole location increases with thrust force firstly but decreases afterward. The influence of thrust force on hole wall roughness is not obvious.


2018 ◽  
Vol 12 (1) ◽  
pp. 175-191 ◽  
Author(s):  
S. Yousefi ◽  
M. Zohoor

Objective: Hard turning in dry condition using cubic boron nitride tools, as an alternative of traditional grinding operation, is an advanced machining operation in which hardened steel with the hardness greater than 46 HRc is machined without the use of any coolant. Method: In the hard turning process, due to its hard nature, usually the cutting depth is selected lower than or equal to the nose radius, and the cutting zone is mainly limited within the tool nose area. Thus, unlike the traditional turning, the effect of the nose radius on the surface finish and dimensional accuracy becomes more complicated. Therefore, in this paper, firstly, the effect of processing parameters such as nose radius on the surface roughness and dimensional accuracy is investigated. Then, the relationship between the surface finish and dimensional accuracy variations with vibration, cutting forces, and tool wear is studied experimentally. The results revealed that feed rate is the most important factor influencing the surface roughness, whereas spindle speed and cutting depth are insignificant factors. On the other hand, cutting depth and spindle speed have the greatest effect on the dimensional accuracy, while nose radius has no significant effect. The vibration and wear analysis revealed that compared with the vibration, the tool wear has no considerable effect on the dimensional accuracy. It was also observed that the spindle speed has a contradictory effect on the surface roughness and dimensional accuracy. The best dimensional accuracy is obtained at 500 rpm, while the best surface quality is achieved at 2000 rpm. Result: The obtained results also showed that increasing the feed rate from a particular value not only leads to no significant changes in the surface roughness value but in some cases can also decrease the surface roughness. Conclusion: According to the analysis results, the lowest cutting depth, the moderate feed rate, and the speed lower than 1100 rpm provide the best dimensional accuracy. Compared with carbides and ceramics, cubic boron nitride tools produce a better surface roughness at both higher cutting depth and speed. 0.202 µm is the best surface roughness that was obtained at rε = 1.2 mm, N = 2000 rpm, f = 0.08 mm/rev, d = 0.5 mm which is comparable with the surface quality obtained by the conventional grinding operation.


2020 ◽  
Vol 24 (1) ◽  
Author(s):  
Sivaranjani Gali ◽  
Suresh Chiru

Objective: For a dental material to be machinable for CAD/CAM technology, it must offer convenient machining, under a given set of cutting conditions. Quantitative evaluation of machinability has been assessed in literature through various parameters such as tool wear, penetration rates, surface roughness, cutting force and power. A machinable ceramic will typically demonstrate a higher tool penetration rate with signs of reduced diamond tool wear and edge chipping. The purpose of this in vitro study was to evaluate the feasibility of machining an experimental ceramic, 20 wt.% zirconia reinforced mica glass ceramics (G20Z) for indirect dental restorations and compare the tool penetration rates of G20Z to commercially available dental ceramics, Presintered Zirconia (PSZ) and IPS emax CAD. Material and Methods:  Precursors of base glass (SiO2 -Al2O3 -K2O -MgO-B2O3 -F) were melted at 15000C for 2 h in a platinum crucible and quenched in deionised water. The glass frit was ball milled with 20 wt. % YSZ (G20Z) and subject to two stage heat treatment in a muffle furnace. Specimens of G20Z (12 X 2 mm) were evaluated for their feasibility of machining under varying spindle speed, depth of cut, and feed rates. Influence of depth of cut, spindle speed and feed rate (vc=8000-16000 rpm, d=0.4-0.8 mm, f=0.1- 0.3 mm/tooth) on cutting forces, material response, surface roughness and tool wear were investigated. Tool penetration rates, tool wear and margin chipping were also evaluated and compared with Pre-sintered Zirconia (PSZ)  and e.max CAD in a custom dental milling surveyor at 30,000 rpm with a load of 0.98 N under water lubrication for 6 min. Tool penetration rates were calculated as the ratio of length of cut and milling time with a measuring microscope and scanning electron microscope was used for tool wear and edge chipping. ANOVA and Tukey Kramer tests were used for statistically comparing the means of each group. Results: Spindle speed and feed rate play a significant role in influencing surface roughness, thrust force, cutting forces and tool wear. Penetration rates of G20Z (0.32 ±0.12 mm/min) was significantly greater than PSZ (0.26 ±0.06 mm/min) and IPS e.max CAD (0.21 ±0.05 mm/min). SEM observations reveal tool abrasion and edge chipping regardless of the ceramic type. Conclusion: High spindle speeds delivers low cutting forces with an average surface roughness of 1.61 µm, with abrasive wear of the tool insert and brittle fracture of zirconia mica glass ceramic composites. G20Z with its machinable nature demonstrates greater tool penetration rates than PSZ and IPS e.max CAD. Tool wear and edge chipping is seen in all the investigated ceramics.   Keywords Machinability, Dental Ceramics, Mica Glass-Ceramics, Dental Zirconia, Tool penetration rates.  


Author(s):  
Jianwei Ma ◽  
Yuanyuan Gao ◽  
Zhenyuan Jia ◽  
Dening Song ◽  
Likun Si

High-speed milling, which provides an efficient approach for high-quality machining, is widely adopted for machining difficult-to-machine materials such as Inconel 718. For high-speed milling of Inconel 718 curved surface parts, the spindle speed which determines cutting speed directly is regarded as an important cutting parameter related to tool wear and machining efficiency. Meanwhile, because of the changing geometric features of curved surface, cutting force is changing all the time with the variation of geometric features, which influences not only tool wear but also machining quality significantly. In this study, the influence of spindle speed on coated tool wear in high-speed milling of Inconel 718 curved surface parts is studied through a series of experiments on considering tool life, cutting force, cutting force fluctuation, and machining efficiency. According to the experimental results, the appropriate spindle speed that can balance both the tool life and the machining efficiency is selected as 10,000 r/min for high-speed milling of Inconel 718 curved surface parts. In addition, the coated tool wear mechanism is investigated through scanning electron microscopy–energy dispersive x-ray spectroscopy analysis. The results show that at the beginning wear stage and the stable wear stage, the coated tool wear is mainly caused by mechanical wear. Then, with the increasing cutting temperature due to the blunt tool edge, the tool wear becomes compound wear which contains more than one wear form so as to cause a severe tool wear.


Author(s):  
Kambiz Haji Hajikolaei ◽  
Masoud Rahaeifard ◽  
Gholamreza Vossoughi ◽  
Mohammadreza Movahhedy

Chatter suppression in machining processes results in more material removal rate, high precision and surface quality. In this paper, a single degree of freedom model of orthogonal turning process is used to set up the delay differential equation of motion with considering the tool wear effect as a contact force between the workpiece and tool flank surfaces. Sinusoidal spindle speed variations with different frequencies around the mean speed are modulated to disturb the regenerative mechanism. The optimal amplitudes of the speed modulations are found based on a genetic algorithm such that the input energy to the turning process is minimized. Results of the stability analysis and the controller effect for two distinct cases of one and three sinusoidal speed are presented and compared.


2019 ◽  
Vol 943 ◽  
pp. 66-71
Author(s):  
Moola Mohan Reddy ◽  
Viviana Yong Chai Nie

This research work considered the high speed milling operation of Inconel 718 using a 4 flute solid carbide end mill tool without the use of coolant. Inconel 718 is a Nickel based Heat Resistance Super Alloy (HRSA) that is vastly used in the aerospace industries due to its excellent corrosion resistance and good mechanical properties. However, Inconel 718 is considered as a difficult-to-cut super alloy, which poses several problems when machining the material. The aim of this work is to investigate the effect and the influence of cutting parameters (feed rate, spindle speed, and depth of cut) on the quality of the machined surface as well as to evaluate the tool wear after machining. This evaluation of the surface roughness was done using a CNC milling machine at various parameters range for the values of feed rate (50-150 mm/min), spindle speed (2000-4000 RPM), and depth of cut (0.05-0.1 mm). The experiment was designed using Response Surface Analysis Method with Central Composite Design (CCD) to optimize the experimentation. The resulting tool wear and surface roughness after high speed machining were then analysed using ANOVA to determine the cutting parameters which is most affecting the surface roughness.


2014 ◽  
Vol 903 ◽  
pp. 194-199
Author(s):  
Mohd Zairulnizam Zawawi ◽  
Mohd Ali Hanafiah Shaharudin ◽  
Ahmad Rosli Abdul Manaf

Machining technique using high spindle speed, high feed rate and shallow depth of cut utilize in High Speed Milling (HSM) machines offer several benefits such as increase of productivity, elimination of secondary and semi-finishing process, reduce tool load and small chips produced. By adjusting some of the machining parameters, non-HSM machine having lower spindle speed and feed rate could also take advantages some of the benefits mentioned above when applying the HSM technique. This experiment investigate the effects of varying combination of depth of cut and feed rate to tool wear rate and surface roughness during end milling of Aluminum and P20 tool steel in dry condition. The criterion for tool wear before it gets rejected is based on maximum flank wear, Vb of 0.6mm. Material removal rate, spindle speed and radial depth of cut are constant in this experiment. After preliminary machining trials, the combination starts with depth of cut of 2mm and feed rate of 45mm/min until the smallest depth of cut and highest feed rate of 0.03mm and 3000mm/min respectively. The obtained result shows that for both materials, feed rate significantly influences the surface roughness value while depth of cut does not as the surface roughness value keep increasing with the increase of feed rate and decreasing depth of cut. Whereas, tool wear rate almost remain unchanged indicates that material removal rate strongly contribute the wear rate. With no significant tool wear rate, this study demonstrates that HSM technique is possible to be applied in non-HSM machine with extra benefits of eliminating semi-finishing operation, reducing tool load for finishing, machining without coolant and producing smaller chip for ease of cleaning.


2021 ◽  
pp. 002199832199807
Author(s):  
Sagar Kubher ◽  
Suhasini Gururaja ◽  
Redouane Zitoune

The evolution of in-situ cutting temperature and machining forces during conventional drilling of multi-directional carbon fiber reinforced polymer (MD-CFRP) laminates using a novel inverted drilling setup is presented. The in-situ cutting temperature was measured using fiber Bragg grating (FBG) optical sensor embedded in the stationary drill. The effect of machining parameters such as spindle speed and feed rate on the temperatures and machining forces were studied that indicate the predominant effect of spindle speed on machining temperatures. The drilled MD-CFRP samples and drill bits were characterized by scanning electron microscopy (SEM) and micro-computed tomography ([Formula: see text]) techniques to assess machining-induced damage in the samples and tool wear in the drill bits. Exit-ply delamination was observed in MD-CFRP samples that aggravates with increase in cutting temperature and thrust force caused by evolving tool wear. The measured in-situ machining temperatures using the current experimental setup can be used to achieve better machining models.


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