INFLUENCE OF THE CUTTING PART GEOMETRY ON STRENGTH OF THE RHOMBIC INDEXABLE INSERT DURING ROUGH TURNING.

Tool wear phenomena during the machining of titanium alloys are very complex. Severe adhesive interaction at the tool chip interface, especially at low cutting speeds, leads to intensive Built Up Edge (BUE) formation. Additionally, a high cutting temperature causes rapid wear in the carbide inserts due to the low thermal conductivity of titanium alloys. The current research studies the effect of AlTiN and CrN PVD coatings deposited on cutting tools during the rough turning of a Ti6Al4V alloy with severe BUE formation. Tool wear characteristics were evaluated in detail using a Scanning Electron Microscope (SEM) and volumetric wear measurements. Chip morphology analysis was conducted to assess the in situ tribological performance of the coatings. A high temperature–heavy load tribometer that mimics machining conditions was used to analyze the frictional behavior of the coatings. The micromechanical properties of the coatings were also investigated to gain a better understanding of the coating performance. It was demonstrated that the CrN coating possess unique micromechanical properties and tribological adaptive characteristics that minimize BUE formation and significantly improve tool performance during the machining of the Ti6Al4V alloy.

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High productivity fluence based control of Directed Energy Deposition (DED) part geometry

Journal of Manufacturing Processes ◽

10.1016/j.jmapro.2021.03.028 ◽

2021 ◽

Vol 65 ◽

pp. 407-417

Author(s):

Geng Li ◽

Kyle Odum ◽

Curtis Yau ◽

Masakazu Soshi ◽

Kazuo Yamazaki

Keyword(s):

Energy Deposition ◽

High Productivity ◽

Part Geometry ◽

Directed Energy Deposition ◽

Directed Energy

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An Experimental Study of Cutting Force on Large Cutting Depth Turning Titanium Alloy with CBN Tool

Materials Science Forum ◽

10.4028/www.scientific.net/msf.800-801.237 ◽

2014 ◽

Vol 800-801 ◽

pp. 237-240

Author(s):

Li Fu Xu ◽

Ze Liang Wang ◽

Shu Tao Huang ◽

Bao Lin Dai

Keyword(s):

Experimental Study ◽

Titanium Alloy ◽

Cutting Force ◽

Feed Rate ◽

Cutting Speed ◽

Cutting Parameters ◽

Cutting Depth ◽

Cbn Tool ◽

Cutting Experiment ◽

Rough Turning

In this paper, the cutting experiment was used to study the influence of various cutting parameters on cutting force when rough turning titanium alloy (TC4) with the whole CBN tool. The results indicate that among the cutting speed, feed rate and cutting depth, the influence of the cutting depth is the most significant on cutting force; the next is the feed rate and the cutting speed is at least.

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Analysis and Modeling of Defects in Unsupported Overhanging Features in Micro-Stereolithography

Volume 4: 21st Design for Manufacturing and the Life Cycle Conference; 10th International Conference on Micro- and Nanosystems ◽

10.1115/detc2016-60092 ◽

2016 ◽

Author(s):

Vito Basile ◽

Francesco Modica ◽

Irene Fassi

Keyword(s):

Finite Element ◽

Numerical Models ◽

Numerical Approach ◽

Fe Analysis ◽

Test Cases ◽

Layer By Layer ◽

Failure Condition ◽

Micro Scale ◽

Part Geometry ◽

Shape Component

In the present paper, a numerical approach to model the layer-by-layer construction of cured material during the Additive Manufacturing (AM) process is proposed. The method is developed by a recursive mechanical finite element (FE) analysis and takes into account forces and pressures acting on the cured material during the process, in order to simulate the behavior and investigate the failure condition sources, which lead to defects in the final part geometry. The study is focused on the evaluation of the process capability Stereolithography (SLA), to build parts with challenging features in meso-micro scale without supports. Two test cases, a cantilever part and a bridge shape component, have been considered in order to evaluate the potentiality of the approach. Numerical models have been tuned by experimental test. The simulations are validated considering two test cases and briefly compared to the printed samples. Results show the potential of the approach adopted but also the difficulties on simulation settings.

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Development of computer-aided machining optimisation for multi-pass rough turning operations

International Journal of Production Economics ◽

10.1016/0925-5273(94)90172-4 ◽

1994 ◽

Vol 37 (2-3) ◽

pp. 215-227 ◽

Cited By ~ 17

Author(s):

P.K. Kee

Keyword(s):

Turning Operations ◽

Computer Aided ◽

Rough Turning ◽

Machining Optimisation

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Wrinkling Prediction and Optimization of Sheet Metal Forming Process by Numerical Simulation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.818.252 ◽

2015 ◽

Vol 818 ◽

pp. 252-255 ◽

Cited By ~ 3

Author(s):

Ján Slota ◽

Marek Šiser

Keyword(s):

Numerical Simulation ◽

Material Model ◽

Mechanical Tests ◽

Simulation Software ◽

Forming Process ◽

Part Geometry ◽

Nominal Thickness ◽

430 Stainless Steel ◽

Metal Forming Process ◽

Aisi 430

The paper deals with optimization of forming process for AISI 430 stainless steel with nominal thickness 0.4 mm. During forming of sidewall for washing machine drum, some wrinkles remain at the end of forming process in some places. This problem was solved by optimization the geometry of the drawpiece using numerical simulation. During optimization a series of modifications of the part geometry to absolute elimination of wrinkling was performed. On the basis of mechanical tests, the material model was created and imported into the material database of Autoform simulation software.

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An In-Process Intervention to Mitigate the Effect of Built-Up Edges in Micromilling

Journal of Micro and Nano-Manufacturing ◽

10.1115/1.4037574 ◽

2017 ◽

Vol 5 (4) ◽

Cited By ~ 1

Author(s):

Robert G. Altman ◽

James F. Nowak ◽

Johnson Samuel

Keyword(s):

Machining Process ◽

Burr Formation ◽

Tool Runout ◽

Part Geometry ◽

Intervention Technique ◽

Mechanical Removal ◽

Working Volume ◽

G Code ◽

Critical Process Parameters ◽

Critical Process

This paper is focused on developing an in-process intervention technique that mitigates the effect of built-up edges (BUEs) during micromilling of aluminum. The technique relies on the intermittent removal of the BUEs formed during the machining process. This is achieved using a three-stage intervention that consists first of the mechanical removal of mesoscale BUEs, followed by an abrasive slurry treatment to remove the microscale BUEs. Finally, the tool is cleaned using a nonwoven fibrous mat to remove the slurry debris. An on-machine implementation of this intervention technique is demonstrated, followed by a study of its influence on key micromachining outcomes such as tool wear, cutting forces, part geometry, and burr formation. In general, all relevant machining measures are found to improve significantly with the intervention. The key attributes of this intervention that makes it viable for micromachining processes include the following: (i) an experimental setup that can be implemented within the working volume of the microscale machine tool; (ii) no removal of the tool from the spindle, which ensures that the intervention does not change critical process parameters such as tool runout and offset values; and (iii) implementation in the form of canned G-code subroutines dispersed within the regular micromachining operation.

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Towards Optimal Flow Uniformity: Stiffener Layout Design Evaluation of Injection Moulded Plastic Part

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.428.33 ◽

2012 ◽

Vol 428 ◽

pp. 33-37

Author(s):

Yi Min Deng ◽

Bao Shou Sun ◽

Hua Bo He ◽

Fu Zhan Shangguan

Keyword(s):

Process Conditions ◽

Flow Uniformity ◽

Plastic Part ◽

Moulding Process ◽

Manufacturing Method ◽

Part Geometry ◽

Stiffener Layout ◽

Plastic Parts ◽

Stiffener Layout Design

Injection moulding is an important manufacturing method for plastic parts. There are however many moulding quality defects caused by inappropriate setting of moulding process conditions, as well as the poorly designed plastic part geometry. Often, stiffeners are used in a plastic part to increase its strength. However, if the stiffeners are not designed properly, they will introduce one or more moulding quality problems, which in turn will worsen the part strength rather than increasing it. Although there have been quite a lot of researches on optimising moulding quality, it is often difficult to minimize multiple quality defects simultaneously. In this paper, we propose to employ flow uniformity as the optimisation objective to address this problem. A number of stiffener layout designs are evaluated in terms of this objective to determine the best design, where standard deviations of filling times and pressures at the extremities of the plastic part are used to measure the uniformity of flow. A simple case study is also presented to demonstrate the applicability of the proposed methodology.

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Vision-Based Precision Deburring and Edge Breaking Process Quality Control

Volume 2: Manufacturing Processes; Manufacturing Systems; Nano/Micro/Meso Manufacturing; Quality and Reliability ◽

10.1115/msec2020-8493 ◽

2020 ◽

Author(s):

Kartik Gupta ◽

Cindy Grimm ◽

Burak Sencer ◽

Ravi Balasubramanian

Keyword(s):

Computer Vision ◽

Quality Control ◽

Vision System ◽

Quality Measures ◽

Cad Model ◽

Computer Vision System ◽

Part Geometry ◽

Specialized Hardware ◽

Original Part

Abstract This paper presents a computer vision system for evaluating the quality of deburring and edge breaking on aluminum and steel blocks. This technique produces both quantitative (size) and qualitative (quality) measures of chamfering operation from images taken with an off-the-shelf camera. We demonstrate that the proposed computer vision system can detect edge chamfering geometry within a 1–2mm range. The proposed technique does not require precise calibration of the camera to the part nor specialized hardware beyond a macro lens. Off-the-shelf components and a CAD model of the original part geometry are used for calibration. We also demonstrate the effectiveness of the proposed technique on edge breaking quality control.

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