Effect of lead on the machinability of brass alloys using polycrystalline diamond cutting tools

2018 ◽  
Vol 53 (8) ◽  
pp. 602-615 ◽  
Author(s):  
Luis Amaral ◽  
Rafael Quinta ◽  
Tiago E Silva ◽  
Rui MB Soares ◽  
Santiago D Castellanos ◽  
...  
Keyword(s):  
Tool Wear ◽  
Cutting Forces ◽  
Cutting Tools ◽  
Polycrystalline Diamond ◽  
Chip Morphology ◽  
Lead Free ◽  
Production Techniques ◽  
Polycrystalline Diamond Inserts ◽  
Brass Alloys

The international safety regulations are pushing the manufacturers of water systems and equipment to remove lead from material compositions due to the potential human hazard of lead absorption. The usage of green lead-free brass alloys is becoming mandatory in many important markets, demanding the manufacturers to quickly adapt their production techniques both casting and machining to this new reality. Regarding machining, lead has been used to facilitate the chip control, working as a natural chip breaker and reducing the tool wear. Therefore, the reduction of lead composition in brass alloys contributes to a machinability decrease of the materials leading to higher cutting forces, long chips and higher tool wear. This work focuses on the machinability characterization of three different brass alloys (leaded, medium-leaded and minimally leaded) by means of cylindrical external turning process with polycrystalline diamond inserts. A parametric study covering three different depths of cuts, three feed rates and four cutting speeds was conducted for three brass alloys with two repetitions. Cutting forces, chip morphology and surface roughness were analysed and compared between alloys. Complementary microstructural and mechanical characterization of the alloys were performed. Analysis of variance was performed to analyse the results. Cutting forces, power consumption, specific cutting pressure, roughness and chip morphology identification were used as comparison criteria among the tested materials. Results have demonstrated the decrease of machinability with the lead reduction, with higher cutting forces and longer chips. Polycrystalline diamond tools used in this work could be a good option to overcome the machinability challenges of the lead-free brass alloys.

scholarly journals Machinability of Rolled Aluminum using Advanced Coated Cutting Tools and its Characterization

2019 ◽  
Vol 8 (3) ◽  
pp. 776-783
Keyword(s):  
Surface Roughness ◽  
Cutting Tool ◽  
Diamond Tool ◽  
Cutting Tools ◽  
Polycrystalline Diamond ◽  
Depth Of Cut ◽  
Constant Depth ◽  
Rolled Aluminum ◽  
Polycrystalline Diamond Inserts

Because of multiple properties like higher values of corrosion resistance, formability, weldability along with greater structural utility aluminum alloys are generally gaining more and more demand in industries and household. With this the requirement for searching of higher quality cutting tool to machine aluminum is also growing. Here different cutting tools like MTCVD+TiCN+Al2O3 , MTCVD+TiCN+Al2O3+TiOCN, MTCVD+TiN+TiCN+Al2O3+TiN, PVD AlTiN, cemented carbide (k-10) insert brazed with Polycrystalline Diamond and Polycrystalline Diamond Inserts are being used to machine rolled aluminum in dry condition and then comparative analysis are made. The cutting is of orthogonal type and capstan lathe is used for the same. Under different conditions of cutting the surface roughness along with morphology of chip are analyzed. Under constant depth of cut (doc) along with variable velocities and feed, the turning operation is performed. With SEM and XRD the identification including characterization of cutting tool were also performed. The polycrystalline diamond tool is found to give optimum surface finish, thin type of chip along with mirror like finish during machining operation.

scholarly journals Enhancing Wear Resistance and Cutting Performance of a Long-Life Micro-Groove Tool in Turning AISI 201

Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1515
Author(s):  
Jinxing Wu ◽  
Lin He ◽  
Yanying Wu ◽  
Chaobiao Zhou ◽  
Zhongfei Zou ◽  
...  
Keyword(s):  
Temperature Field ◽  
Service Life ◽  
Tool Wear ◽  
Cutting Forces ◽  
Cutting Tools ◽  
Cutting Temperature ◽  
Rake Angle ◽  
Rake Face ◽  
Crater Wear ◽  
Wear Area

Tool-chip friction increases cutting temperature, aggravates tool wear, and shortens the service life of cutting tools. A micro-groove design of the rake face can improve the wear performance of the tool. In this study, we used the finite element simulation “Deform” to obtain the temperature field distribution of the tool rake face. The size of the micro-groove was determined by selecting a suitable temperature field combined with the characteristics of tool–chip flow in the cutting process, and the tool was prepared using powder metallurgy. The three-direction cutting forces and tool tip temperature were obtained by a cutting test. Compared with the original turning tool, the cutting force and cutting temperature of the micro-groove tool were reduced by more than 20%, the friction coefficient was reduced by more than 14%, the sliding energy was reduced and the shear energy was greatly decreased. According to the analysis of tool wear by SEM (scanning electron microscope) and EDS (energy dispersive X-ray spectroscopy), the crater wear, adhesive wear and oxidation wear of the micro-groove tool were lower than those of the original turning tool. In particular, the change in the crater wear area on the rake face of the original tool and the micro-groove tool was consistent with the cutting temperature and the wear width of the flank face. On the whole, the crater wear area and the change rate of the crater wear area of the micro-groove tool were smaller. Due to the proper microgroove structure of the rake face, the tool-chip contact area decreased, and the second rake angle of the tool became larger. Hence, the tool-chip friction, cutting forces, cutting energy consumption were reduced, tool wear was improved, and the service life of the micro-groove tool was five times longer than that of the original tool.

The effect of monolayer TiCN-, AlTiN-, TiAlN-and two layers TiCN + TiN- and AlTiN + TiN-coated cutting tools on tool wear, cutting force, surface roughness and chip morphology during high-speed milling of Ti6Al4V titanium alloy

2016 ◽  
Vol 232 (7) ◽  
pp. 1273-1286 ◽  
Author(s):  
Emel Kuram
Keyword(s):  
Surface Roughness ◽  
Titanium Alloy ◽  
Tool Wear ◽  
Cutting Force ◽  
High Speed ◽  
Cutting Tools ◽  
Chip Morphology ◽  
High Speed Milling ◽  
Ti6al4v Titanium Alloy ◽  
Coated Carbide

Tool coatings can improve the machinability performance of difficult-to-cut materials such as titanium alloys. Therefore, in the current work, high-speed milling of Ti6Al4V titanium alloy was carried out to determine the performance of various coated cutting tools. Five types of coated carbide inserts – monolayer TiCN, AlTiN, TiAlN and two layers TiCN + TiN and AlTiN + TiN, which were deposited by physical vapour deposition – were employed in the experiments. Tool wear, cutting force, surface roughness and chip morphology were evaluated and compared for different coated tools. To understand the tool wear modes and mechanisms, detailed scanning electron microscope analysis combined with energy dispersive X-ray of the worn inserts were conducted. Abrasion, adhesion, chipping and mechanical crack on flank face and coating delamination, adhesion and crater wear on rake face were observed during high-speed milling of Ti6Al4V titanium alloy. In terms of tool wear, the lowest value was obtained with TiCN-coated insert. It was also found that at the beginning of the machining pass TiAlN-coated insert and at the end of machining TiCN-coated insert gave the lowest cutting force and surface roughness values. No change in chip morphology was observed with different coated inserts.

Si Particle Size-Controlled Al-17 Mass% Si Alloy and Tool Wear in Cutting Al-17 Mass% Si Alloy by Polycrystalline Diamond Compact Cutting Tool

2015 ◽  
Vol 798 ◽  
pp. 372-376
Author(s):  
Tadahiro Wada
Keyword(s):  
Particle Size ◽  
Aluminum Alloys ◽  
Tool Wear ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Polycrystalline Diamond ◽  
Water Cooling ◽  
Cooling Speed ◽  
High Silicon ◽  
Polycrystalline Diamond Compact

As high silicon aluminum alloys have both a high strength-to-weight ratio and good wear-resistance, they are used for many automobile and motorbike parts. High silicon aluminum alloys are generally machined to improve dimensional accuracy. In cutting high silicon aluminum alloys such as Al-17mass%Si alloy, the primary Si particles have a negative influence on tool wear. Therefore, polycrystalline diamond compact cutting tools are widely used. In this study, in order to improve the tool wear resistance of polycrystalline diamond compact cutting tools, the Si particle size of Al-17 mass% Si alloy was changed by adjusting the water-cooling speed. Two different kinds of Si particle size, which were changed by adjusting the water-cooling speed, were used. The Al-17mass%Si alloy was turned with the polycrystalline diamond compact cutting tool and the tool wear was experimentally investigated. The main results were as follows: (1) The formed Si particle size was from 30 to 70 μm or from 40 to 170 μm. (2) The mechanical properties of the Al-17 mass% Si alloy did not depend on the Si particle size. (3) The Si particle size included in the Al-17 mass% Si alloy had a major influence of the tool wear, and it was possible to reduce the tool wear by increasing the Si particle size including that in the Al-17 mass% Si alloy.

Surface topography characterization of brass alloys: lead brass (CuZn39Pb3) and lead free brass (CuZn21Si3P)

2017 ◽  
Vol 5 (2) ◽  
pp. 025001 ◽  
Author(s):  
Vijeth V Reddy ◽  
Amogh Vedantha Krishna ◽  
Fredrik Schultheiss ◽  
B-G Rosén
Keyword(s):  
Surface Topography ◽  
Lead Free ◽  
Brass Alloys

Improvement of Tool Life of a Commercial Drill Bits by Cryogenic Treatment While Machining Widmanstatten Ti-6Al-4V.

2021 ◽  
Author(s):  
Abdullah Sert ◽  
Fatih Hayati ÇAKIR
Keyword(s):  
Tool Wear ◽  
Tool Life ◽  
Cutting Forces ◽  
Cutting Tool ◽  
Cryogenic Treatment ◽  
Cutting Tools ◽  
Drill Bit ◽  
Deep Cryogenic Treatment ◽  
Drill Bits ◽  
Stereo Microscope

Abstract In this study, the performance of Ø 8 mm WC-Co (10%) drill bits with a TiAlN coating was tested for machining of Ti6Al4V alloy with a Widmanstatten structure. In order to improve the tool life, cutting tools were subjected to deep cryogenic treatment. In total, three groups of tools were prepared for this study. The first group was used for reference as the supplied state; the second group was subjected to 24 hours deep cryogenic treatment at -196 ° C, and the third group was subjected to 24 hours deep cryogenic at -196 ° C, additionally was tempered 2 hours at 200 ° C. Machining experiments were done by drilling and a set of 60 holes were drilled with each drill bit, and tool wear were observed and recorded with a stereo microscope. Additionally, Scanning Electron Microscope (SEM) and Energy Dispersive Spectroscopy (EDS) analyses were carried on to understand the tool wear better. The microhardness of Cryo-treated and tempered cutting tools hardness increased up to 20 Hv (about 1%), and the toughness value did not change significantly. Cutting performance was observed by measuring the cutting forces during drilling experiments. According to these results, deep cryogenic treatment on WC-Co-based inserts decreased cutting forces by approximately 7% compared to the reference drill bit, which affected the cutting tool life. The dominant wear mechanism was Built-up edge (BUE) formation, and cryo-treatment lowered the BUE amount 8% and cryo-treated and tempered drill bit 45% compared to the reference drill bit.

Machining Characteristics of High Speed Dry Milling of Biodegradable Magnesium-Calcium Alloy

2010 ◽  
Author(s):  
M. Salahshoor ◽  
Y. B. Guo
Keyword(s):  
High Speed ◽  
Cutting Speed ◽  
Stress Shielding ◽  
Polycrystalline Diamond ◽  
Chip Morphology ◽  
Cutting Parameters ◽  
Depth Of Cut ◽  
Degradable Biomaterials ◽  
On Line ◽  
Polycrystalline Diamond Inserts

Metallic degradable biomaterials have attracted a huge attention lately for orthopedic fixation applications. Binary magnesium and calcium (Mg-Ca) alloys have emerged as a promising choice in terms of biocompatibility to avoid stress shielding and provide sufficient mechanical strength. In this paper, efficient and ecologic machining of a lab-made Mg-Ca alloy with 0.8 wt% calcium, cutting speeds of up to 47 m/s, and without coolant are investigated. Polycrystalline diamond inserts are applied and the possibilities of flank built-up formation, chip ignition, and tool wear are sought during the cutting experiments with the aid of a developed on-line, optical monitoring system. Chip morphology characteristics produced by different combinations of cutting parameters, i.e. cutting speed, feed, and depth of cut are studied.

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