Feasibility Study on Grinding of Titanium Alloys with Electroplated CBN Wheels

2013 ◽  
Vol 797 ◽  
pp. 73-78 ◽  
Author(s):  
Zhong De Shi ◽  
Helmi Attia
Keyword(s):  
Titanium Alloy ◽  
Titanium Alloys ◽  
Material Removal ◽  
High Pressures ◽  
Surface Cleaning ◽  
Depth Of Cut ◽  
Wheel Surface ◽  
Removal Rates ◽  
Grinding Fluid ◽  
Creep Feed

An experimental investigation is reported on the grinding of a titanium alloy using electroplated CBN wheels with water-based grinding fluid and wheel surface cleaning fluid applied at high pressures. This work was motivated by applying grinding fluid and wheel surface cleaning fluid both at high pressures for avoiding wheel loading, which is commonly seen in titanium alloy grinding. The objective is to explore the feasibility to grind titanium alloys with electroplated CBN wheels and high pressure wheel surface cleaning fluid for enhancing material removal rates. Straight surface grinding experiments were conducted on titanium alloy blocks in both shallow depth of cut and creep-feed modes. Grinding power, forces, and surface roughness were measured. Specific material removal rates of 8 mm2/s in shallow cut mode and 3 mm2/s at a depth of cut as high as 3 mm in creep-feed mode were achieved without burning and smearing of ground surfaces. It was showed that it is feasible to grind titanium alloys with electroplated CBN wheels at enhanced removal rates by applying grinding and wheel cleaning fluid at high pressures.

An Experimental Study on High Speed Grinding of Granite with a Segmented Diamond Wheel

2009 ◽  
Vol 404 ◽  
pp. 149-156
Author(s):  
Xi Peng Xu ◽  
X.W. Zhu ◽  
Yuan Li
Keyword(s):  
Experimental Study ◽  
Surface State ◽  
Material Removal ◽  
Depth Of Cut ◽  
Vertical Force ◽  
Wheel Surface ◽  
Removal Rates ◽  
Grinding Speed ◽  
Wide Range ◽  
Force Components

An experimental study was undertaken to investigate the grinding of granite at different grinding speeds over a wide range of material removal rates. A metal-bonded diamond blade was used as the grinding wheel with natural gray granite as the workpiece material. The tangential and normal force components were obtained through measuring the horizontal and vertical force components as well as the consumed power. The experiments were conducted with a constant wheel surface state to study the influence of grinding speed under different material removal rates. An additional test was also carried out to examine the grinding process while the wheel surface state progressively changed, in which case both forces and the morphologies of diamond grains were monitored at regular intervals. At a fixed material removal rate, both the tangential and normal forces reduced slightly with the grinding speed. But the specific energy increased greatly at higher grinding speeds especially at a shallower maximum grain depth of cut.

Secondary Machining Characteristics of Additive Manufactured Titanium Alloy Ti-6Al-4V

2018 ◽  
Vol 779 ◽  
pp. 149-152 ◽  
Author(s):  
Ashwin Polishetty ◽  
Basil Raju ◽  
Guy Littlefair
Keyword(s):  
Titanium Alloy ◽  
Titanium Alloys ◽  
Dimensional Accuracy ◽  
Machining Process ◽  
Depth Of Cut ◽  
Machining Parameters ◽  
Wide Range ◽  
Secondary Operations ◽  
Cylindrical Workpiece ◽  
Almost All

Titanium alloy, Ti-6Al-4V is a popular alloy used in wide range of design applications mostly in aerospace and biomedical industry due to its advantageous material properties. This research is based on threading operation in a cylindrical workpiece of Ti-6Al-4V additive manufactured by Selective Laser Melting (SLM) technique. Secondary machining is described as the operations that are performed on the workpiece after a primary machining in order to achieve a required finish and form. Common secondary operations after drilling includes threading, reaming and knurling. Threading is a significant machining process in almost all applications of Titanium alloys. The development of an efficient threading process for Titanium alloys and enhancing existing methods may lead to a wider application of additive manufactured Titanium alloys. The aim of this research is to find out favorable threading conditions for Titanium alloy Ti-6Al-4V to obtain better machinability. Threads are tapped into the workpiece using variable machining parameters such as spindle speed and depth of cut. Statistical data are collected and analyzed by qualitative and quantitative evaluation of the threads. The outputs under consideration to evaluate efficiency of the secondary machining include surface texture (roughness (Ra)), dimensional accuracy (thread geometry) and power required (cutting force).

scholarly journals Towards Optimization of Surface Roughness and Productivity Aspects during High-Speed Machining of Ti–6Al–4V

Materials ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 3749 ◽  
Author(s):  
Adel T. Abbas ◽  
Neeraj Sharma ◽  
Saqib Anwar ◽  
Faraz H. Hashmi ◽  
Muhammad Jamil ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Tool Wear ◽  
Titanium Alloys ◽  
Material Removal Rate ◽  
Material Removal ◽  
High Speed ◽  
Removal Rate ◽  
Depth Of Cut ◽  
Optimization Approach ◽  
High Speed Machining

Nowadays, titanium alloys are achieving a significant interest in the field of aerospace, biomedical, automobile industries especially due to their extremely high strength to weight ratio, corrosive resistance, and ability to withstand higher temperatures. However, titanium alloys are well known for their higher chemical reactive and low thermal conductive nature which, in turn, makes it more difficult to machine especially at high cutting speeds. Hence, optimization of high-speed machining responses of Ti–6Al–4V has been investigated in the present study using a hybrid approach of multi-objective optimization based on ratio analysis (MOORA) integrated with regression and particle swarm approach (PSO). This optimization approach is employed to offer a balance between achieving better surface quality with maintaining an acceptable material removal rate level. The position of global best suggested by the hybrid optimization approach was: Cutting speed 194 m/min, depth of cut of 0.1 mm, feed rate of 0.15 mm/rev, and cutting length of 120 mm. It should be stated that this solution strikes a balance between achieving lower surface roughness in terms of Ra and Rq, with reaching the highest possible material removal rate. Finally, an investigation of the tool wear mechanisms for three studied cases (i.e., surface roughness based, productivity-based, optimized case) is presented to discuss the effectiveness of each scenario from the tool wear perspective.

3D Numerical Investigation of Effect of Milling Process Parameters on High Speed Milling of Ti-Al6-V4

2012 ◽  
Author(s):  
J. Ma ◽  
Shuting Lei ◽  
Huaqi Lu
Keyword(s):  
Titanium Alloy ◽  
Titanium Alloys ◽  
Numerical Investigation ◽  
Process Parameters ◽  
High Speed ◽  
Chemical Reactivity ◽  
Milling Process ◽  
Depth Of Cut ◽  
High Speed Milling ◽  
Axial Depth

Titanium alloys are widely used in aerospace industry owing to excellent mechanical properties. While because of high chemical reactivity and low thermal conductivity, titanium alloys are classified as hard-to-cut materials. In this paper, Finite Element Method (FEM) is employed to conduct numerical investigation in the effects of milling process parameters (milling speeds, feed per tooth, and axial depth of cut) on three-dimensional (3D) high speed milling of Titanium alloy (Ti-6Al-4V). The tool material used is Carbide and Johnson-Cook plastic model is employed to model the workpiece due to its capability of modeling large strains, high strain rates, and temperature dependent visco-plasticity. Different milling speeds, feed per tooth, and axial depth of cut are used to explore the effects of the milling process parameters on the cutting temperature, cutting forces, and power required for machining. This model provides fundamental understanding of cutting mechanics of the 3D high speed milling of Titanium alloy (Ti-6Al-4V).

scholarly journals Experimental Investigation on Machinability of Titanium Alloy by Laser-Assisted End Milling

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1552
Author(s):  
Dong-Hyeon Kim ◽  
Choon-Man Lee
Keyword(s):  
Surface Roughness ◽  
Experimental Investigation ◽  
Titanium Alloy ◽  
Titanium Alloys ◽  
Cutting Force ◽  
Cutting Tool ◽  
End Milling ◽  
Chemical Reactivity ◽  
Depth Of Cut ◽  
Laser Assisted Machining

The Machining of titanium alloys is challenging because of their high strength, low thermal conductivity, high chemical reactivity, and high stresses at the cutting tool edges. Laser-assisted machining is an effective way to improve the machinability of titanium alloys. This paper presents an experimental investigation of the machinability of cutting force and surface roughness in laser-assisted end milling of titanium alloy Ti-6Al-4V. The absorptivity of Ti-6Al-4V was determined by conducting preheating experiments using a high-power diode laser with a wavelength of 940–980 nm. A thermal analysis was performed using the finite element method to predict temperature distribution. The depth of cut was determined where tensile strength decreased sharply, and the predicted surface temperature is presented in the analysis results. The experiments were performed with conventional machining and laser-assisted machining. Surface roughness, tool wear, and cutting force were evaluated. In contrast to the results of conventional end milling, laser-assisted end milling improved surface roughness. Moreover, laser-assisted end milling proved more effective than conventional end milling in terms of cutting tool damage. Our results proved that heat assistance significantly influenced the magnitude of the cutting forces—while the actual reduction in forces varied slightly depending on the force component, cutting tool, and cutting conditions, force components showed a reduction of roughly 13–46%.

scholarly journals A New Cutting Tool Design for Cryogenic Machining of Ti–6Al–4V Titanium Alloy

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 477 ◽  
Author(s):  
Alborz Shokrani ◽  
Stephen Newman
Keyword(s):  
Titanium Alloy ◽  
Titanium Alloys ◽  
Tool Life ◽  
Material Removal Rate ◽  
Surface Integrity ◽  
Material Removal ◽  
Cutting Tool ◽  
Removal Rate ◽  
Cutting Speed ◽  
Cryogenic Machining

Titanium alloys are extensively used in aerospace and medical industries. About 15% of modern civil aircrafts are made from titanium alloys. Ti–6Al–4V, the most used titanium alloy, is widely considered a difficult-to-machine material due to short tool life, poor surface integrity, and low productivity during machining. Cryogenic machining using liquid nitrogen (LN2) has shown promising advantages in increasing tool life and material removal rate whilst improving surface integrity. However, to date, there is no study on cutting tool geometry and its performance relationship in cryogenic machining. This paper presents the first investigation on various cutting tool geometries for cryogenic end milling of Ti–6Al–4V alloy. The investigations revealed that a 14° rake angle and a 10° primary clearance angle are the most suitable geometries for cryogenic machining. The effect of cutting speed on tool life was also studied. The analysis indicated that 110 m/min cutting speed yields the longest tool life of 91 min whilst allowing for up to 83% increased productivity when machining Ti–6Al–4V. Overall the research shows significant impact in machining performance of Ti–6Al–4V with much higher material removal rate.

scholarly journals Adaptive Active Vibration Control for Machine Tools with Highly Position-Dependent Dynamics

2018 ◽  
Vol 12 (5) ◽  
pp. 631-641 ◽  
Author(s):  
Robin Kleinwort ◽  
◽  
Jonathan Platz ◽  
Michael F. Zaeh
Keyword(s):  
Vibration Control ◽  
Machine Tools ◽  
Material Removal ◽  
Control Strategies ◽  
Active Vibration Control ◽  
Adaptive Controller ◽  
Depth Of Cut ◽  
Removal Rates ◽  
Active Vibration ◽  
Free Material

The material removal rates of machine tools are often limited by chatter, which is caused by the machine’s most flexible structural modes. Active vibration control systems mitigate chatter vibrations and increase the chatter free axial depth of cut. However, model-based control strategies reach their limit if the machine tool exhibits highly position-dependent dynamics. In this paper, an adaptive control strategy is presented. This strategy uses online system identification to adapt the controller. The adaption algorithm is mainly automated. However, a few parameters still need to be selected. Therefore, a methodology for the determination of the optimal parameters is proposed. The adaptive controller was implemented on a B&R PLC and its suitability was verified experimentally by the observation of notable increases in the chatter-free material removal rates.

scholarly journals Investigation of Tool Wear and Chip Morphology in Dry Trochoidal Milling of Titanium Alloy Ti–6Al–4V

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 1937 ◽  
Author(s):  
Dongsheng Liu ◽  
Ying Zhang ◽  
Ming Luo ◽  
Dinghua Zhang
Keyword(s):  
Titanium Alloy ◽  
Tool Wear ◽  
Titanium Alloys ◽  
High Efficiency ◽  
Cutting Speed ◽  
Chip Thickness ◽  
Chip Morphology ◽  
Depth Of Cut ◽  
Trochoidal Milling ◽  
Radial Depth

Titanium alloys are widely used in the manufacture of aircraft and aeroengine components. However, tool wear is a serious concern in milling titanium alloys, which are known as hard-to-cut materials. Trochoidal milling is a promising technology for the high-efficiency machining of hard-to-cut materials. Aiming to realize green machining titanium alloy, this paper investigates the effects of undeformed chip thickness on tool wear and chip morphology in the dry trochoidal milling of titanium alloy Ti–6Al–4V. A tool wear model related to the radial depth of cut based on the volume of material removed (VMR) is established for trochoidal milling, and optimized cutting parameters in terms of cutting speed and axial depth of cut are selected to improve machining efficiency through reduced tool wear. The investigation enables the environmentally clean rough machining of Ti–6Al–4V.

Experimental Study on Creep Feed Deep Grinding Titanium Alloy with Slotted CBN Grinding Wheel

2006 ◽  
Vol 304-305 ◽  
pp. 166-170 ◽  
Author(s):  
Yu Can Fu ◽  
Hong Jun Xu ◽  
Fang Hong Sun
Keyword(s):  
High Pressure ◽  
Titanium Alloy ◽  
Titanium Alloys ◽  
High Efficiency ◽  
Removal Rate ◽  
Jet Impingement ◽  
Research Orientation ◽  
Creep Feed ◽  
Fluid Supply ◽  
Cooling Enhancement

In order to improve the grindability of titanium alloys, the inhibition of chemical affinity between abrasives and titanium alloys and cooling enhancement in grinding zone are carried out in this paper. Slotted electroplated CBN grinding wheels with optimum topography are used, and different grinding fluid supply systems such as conventional tangential spraying coolant supply, inner chamber coolant jet impingement, radial high-pressure coolant jet impingment are employed in creep feed deep grinding experiments on titanium alloy (TC4). The experimental results show that high-pressure jet impingement has remarkable cooling effect. The temperature of the workpiece surface can be steadily kept below the critical film boiling temperature 120~130°C, while the workpiece surfaces is badly burnt with conventional coolant supply. The study will exploit an important research orientation that has great potential in high efficiency grinding. Further perfection of this study will not only enable us to increase the available material removal rate to a new level but also solve the workpiece burn problem of the difficult-to-machining materials in high efficiency grinding.In order to improve the grindability of titanium alloys, the inhibition of chemical affinity between abrasives and titanium alloys and cooling enhancement in grinding zone are carried out in this paper. Slotted electroplated CBN grinding wheels with optimum topography are used, and different grinding fluid supply systems such as conventional tangential spraying coolant supply, inner chamber coolant jet impingement, radial high-pressure coolant jet impingment are employed in creep feed deep grinding experiments on titanium alloy (TC4). The experimental results show that high-pressure jet impingement has remarkable cooling effect. The temperature of the workpiece surface can be steadily kept below the critical film boiling temperature 120~130°C, while the workpiece surfaces is badly burnt with conventional coolant supply. The study will exploit an important research orientation that has great potential in high efficiency grinding. Further perfection of this study will not only enable us to increase the available material removal rate to a new level but also solve the workpiece burn problem of the difficult-to-machining materials in high efficiency grinding.

Grinding Wheel Surface Topography for Multiple Pass With Incremental Depth of Cut of Rotary Diamond Dresser

2015 ◽  
Author(s):  
M. A. K. Chowdhury
Keyword(s):  
Surface Topography ◽  
Removal Efficiency ◽  
Material Removal ◽  
Cutting Tools ◽  
Depth Of Cut ◽  
Grinding Wheel ◽  
Simulation Tool ◽  
Wheel Surface ◽  
Working Surface ◽  
Multiple Pass

Grinding is often used material removal process in manufacturing. A grinding wheel has abrasive grains on its working surface and the material removal efficiency of a grinding wheel decreases with grinding operations. To restore the material removal efficiency of a grinding wheel, dressing is performed. There are several types of dressing methods and among these different methods, mechanical dressing is widely performed. In mechanical dressing, rotary diamond dresser is one of the effective dressers. The grinding wheel surface topography induced from dressing effect the performance of subsequent grinding operation. Therefore, grinding wheel preparation conditions, i.e., dressing conditions and consequently the grinding wheel surface topography have effect on grinding performance. The actual cutting points on diamond grits of a rotary diamond dresser are micro cutting tools which interact with the working surface of the grinding wheel. This interaction of the diamond grits of rotary diamond dresser restores the material removal efficiency of the grinding wheel. In precision engineering, multiple pass and incremental depth of cut of dresser is applied to increase the overall efficiency. This study deals with the surface topography of grinding wheel due to multiple pass and incremental depth of cut dressing operations by rotary diamond dresser. The objective of a dressing operation is to sharpen and protrude the abrasive grits embedded on the working surface of a grinding wheel. To achieve this, the rotary dresser should come in contact with all parts of the working surface of a grinding wheel without hitting the same location repeatedly. A simulation tool has been developed correlating the rotary diamond dresser parameters, grinding wheel parameters and dressing process parameters. In this research, a method is developed which enables one to determine the trajectories of dresser on the working surface of a grinding wheel (i.e., surface topography of grinding wheel) after performing dressing operations multiple times wherein the depth of cut is increased after each pass. A modified simulation is used to visualize surface topography of a grinding wheel for multiple pass with incremental depth of cut. The simulation tool also determines the dressing ratio (percent of working area of grinding wheel that has been dressed) and the areas which are dressed twice or more. Using the modified simulation tool, some strategies, i.e., single pass and multi pass dressing with incremental depth of cut is identified for determining optimal dressing conditions (the dressing conditions for which the dresser covers all circumferential surface of a grinding wheel without dressing the same area repeatedly).

Sign in / Sign up

Export Citation Format

Share Document