Transient temperature monitoring and safe cutting speed exploration in diamond turning of PBX surrogates

2021 ◽  
Author(s):  
Zhimin Cao ◽  
Wenjun Zong ◽  
Chunlei He ◽  
Jiaohu Huang ◽  
Wei Liu ◽  
...  
Keyword(s):  
Cutting Speed ◽  
Temperature Monitoring ◽  
Diamond Turning ◽  
Transient Temperature

Microtexture Generation Using Controlled Chatter Machining in Ultraprecision Diamond Turning

2015 ◽  
Vol 3 (2) ◽  
Author(s):  
Syed Adnan Ahmed ◽  
Jeong Hoon Ko ◽  
Sathyan Subbiah ◽  
Swee Hock Yeo
Keyword(s):  
Cutting Tool ◽  
Cutting Speed ◽  
Diamond Turning ◽  
Diamond Cutting ◽  
Machined Surface ◽  
Excited Vibration ◽  
Mass And Heat Transfer ◽  
Tool Shank ◽  
Diamond Cutting Tool

This paper describes a new method of microtexture generation in precision machining through self-excited vibrations of a diamond cutting tool. Conventionally, a cutting tool vibration or chatter is detrimental to the quality of the machined surface. In this study, an attempt is made to use the cutting tool's self-excited vibration during a cutting beneficially to generate microtextures. This approach is named as “controlled chatter machining (CCM).” Modal analysis is first performed to study the dynamic behavior of the cutting tool. Turning processes are then conducted by varying the tool holder length as a means to control vibration. The experimental results indicate that the self-excited diamond cutting tool can generate microtextures of various shapes, which depend on the cutting tool shank, cutting speed, feed, and cutting depth. The potential application of this proposed technique is to create microtextures in microchannels and microcavities to be used in mass and heat transfer applications.

Modelling of Electrostatic Charge in Ultra-High Precision Diamond Turning of Contact Lens Polymer

2019 ◽  
Vol 298 ◽  
pp. 135-140
Author(s):  
Muhammad Mukhtar Liman ◽  
Khaled Abou El Hossein
Keyword(s):  
High Precision ◽  
Contact Lens ◽  
Feed Rate ◽  
Contact Lenses ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Electrostatic Charge ◽  
Diamond Turning ◽  
Depth Of Cut ◽  
Electrostatic Charges

The electrostatic charges encountered by a cutting tool when turning advanced contact lenses are important as they reflect the quality and condition of the tool, machine, fixture, and sometimes even the surface finished which is responsible for tool wear and poor surface quality. This study investigates the influence of cutting parameters namely cutting speed, feed rate and depth of cut on electrostatic charge (ESC) which play the leading role in determining the machine economics and quality of machining contact lens polymers. An electrostatic charge model based on response surface statistical method is developed for reliably predicting the values of static charging based on its relationship to cutting parameters in ultra-high precision diamond turning of contact lenses. It is clearly seen that all the model terms are significant with cutting speed having the highest degree of significance followed by feed rate and the interaction of speed and feed. However, depth of cut has the lowest degree of significance on the electrostatics charge.

Effects of Machining Parameters on Surface Roughness when Ultra-High Precision Diamond Turning RSA443 Optical Aluminum

2019 ◽  
Vol 287 ◽  
pp. 30-34
Author(s):  
Zwelinzima Mkoko ◽  
Khaled Abou-El-Hossein
Keyword(s):  
Surface Roughness ◽  
Silicon Content ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Diamond Turning ◽  
Machining Parameters ◽  
Turning Process ◽  
Optical Components ◽  
Box Behnken Design ◽  
Factors Influencing

In the globally competitive environment, surface roughness and finer tolerances are becoming stringent and certainly most critical for optical components. The aim of this study is to determine the effects of diamond turning process parameters on surface finish when diamond turning RSA 443 alloy having high silicon content. This alloy is a new grade of aluminum that has a potential to be used for production of various optical components. The experiments were conducted based on the Box-Behnken design with three diamond-turning parameters varied at three levels. A mathematical regression model was developed for predicting surface roughness. Further, the analysis of variance was used to analyze the influence of cutting parameters and their interaction in machining. The developed prediction model reveals that cutting speed and feed rate are the most dominant diamond turning factors influencing surface roughness.

Finite Element Analysis of Ultrasonic Vibration Assisted Turning of Ferrous Metals

2013 ◽  
Vol 567 ◽  
pp. 33-38 ◽  
Author(s):  
Lai Zou ◽  
Ming Zhou
Keyword(s):  
Finite Element ◽  
Tool Wear ◽  
Ultrasonic Vibration ◽  
Single Point ◽  
Cutting Temperature ◽  
Cutting Speed ◽  
Diamond Turning ◽  
Depth Of Cut ◽  
Technological Parameters ◽  
Ferrous Metals

Ultrasonic vibration assisted turning has significant improvements in processing of intractable materials compared to conventional turning. This paper presents a theoretical investigation of tool wear in single point diamond turning of ferrous metals based on numerical simulation. Finite element modeling and simulation of ultrasonic vibration turning process were performed, aimed at optimizing a series of technological parameters in the process of machining, reducing tool wear and improving surface quality as much as possible. The results revealed that the cutting speed and depth of cut are two crucial factors for tool wear, unlike the other parameters of vibration frequency, amplitude and flank angle. Moreover, this technological measure has observably decreased the cutting force and cutting temperature, so as to obtain superior surface finish.

Forecasting of Surface Roughness and Cutting Force in Single Point Diamond Turning for KDP Crystal

2007 ◽  
Vol 339 ◽  
pp. 78-83 ◽  
Author(s):  
Jing He Wang ◽  
Shen Dong ◽  
H.X. Wang ◽  
Ming Jun Chen ◽  
Wen Jun Zong ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Prediction Model ◽  
Cutting Force ◽  
Single Point ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Diamond Turning ◽  
Depth Of Cut ◽  
Kdp Crystal ◽  
Optimal Cutting Parameters

The method of single point diamond turning is used to machine KDP crystal. A regression analysis is adopted to construct a prediction model for surface roughness and cutting force, which realizes the purposes of pre-machining design, prediction and control of surface roughness and cutting force. The prediction model is utilized to analyze the influences of feed, cutting speed and depth of cut on the surface roughness and cutting force. And the optimal cutting parameters of KDP crystal on such condition are acquired by optimum design. The optimum estimated values of surface roughness and cutting force are 7.369nm and 0.15N, respectively .Using the optimal cutting parameters, the surface roughness Ra, 7.927nm, and cutting force, 0.19N, are obatained.

Effect of cutting parameters on surface quality during diamond turning of micro-prism array

2016 ◽  
Vol 231 (3) ◽  
pp. 555-561 ◽  
Author(s):  
Dongxu Wu ◽  
Peng Zhang ◽  
Huiming Wang ◽  
Zheng Qiao ◽  
Bo Wang
Keyword(s):  
Surface Quality ◽  
Surface Defects ◽  
Cutting Speed ◽  
Side Surface ◽  
Cutting Parameters ◽  
Diamond Turning ◽  
Dominant Factor ◽  
Controlled Cooling ◽  
Cutting Depth ◽  
Ultra Precision

In order to achieve the high-quality roller mold used in roll-to-roll fabrication of optical prism films, this article investigates the effects of cutting parameters on surface quality during diamond turning of micro-prism array, and some cutting experiments are carried out on home-made ultra-precision drum roll lathe. The surface defects such as micro pits and burrs are presented and discussed at different cutting parameters. The experimental results show that, when the cutting depth is more than 4 µm, the plowing force becomes the dominant factor to remove material, which may cause the generation of micro pits on the side surface of micro prism. During multiple-step diamond turning of micro-prism array, the final cutting depth is recommended not to exceed 2 µm; in this case, there is no generation of micro pits and the height of burr is less than 13.6 nm. Moreover, the well-controlled cooling and chip evacuation can effectively improve the influence of cutting speed on surface quality. Finally, micro-prism array with pitch of 40 µm is successfully machined without apparent surface defects.

Research on Transient Temperature of Cutting Tool during High Speed Slot Milling of AISI H13

2014 ◽  
Vol 800-801 ◽  
pp. 715-719
Author(s):  
Fu Lin Jiang ◽  
Zhan Qiang Liu ◽  
Yi Wan ◽  
Han Zhang
Keyword(s):  
High Speed ◽  
Cutting Tool ◽  
Cutting Speed ◽  
Transient Temperature ◽  
H13 Steel ◽  
Tool Insert ◽  
Slot Milling ◽  
Aisi H13 Steel ◽  
Aisi H13 ◽  
Cutting Model

Cutting tool temperature is the main factor that directly affects tool wear and tool life. In this paper we developed temperature model of tool insert during slot milling process, constructed by a combination of cutting time model and non-cutting model. A set of experiments are designed and carried out to obtain cutting induced temperatures at different cutting speeds during slot milling of AISI H13 steel. Experiments results indicate that tool insert temperature increases first and then decreases as the cutting speed grows, and a critical cutting speed for the tool insert temperature exists during slot milling of AISI H13 steel. Some possible reasons for the drop of tool insert temperature are proposed and discussed, and they are decreased heat flux into tool insert and increased heat convection coefficient.

scholarly journals Machinability Investigation for Cellulose Nanofiber-Reinforced Polymer Composite by Ultraprecision Diamond Turning

2021 ◽  
Vol 15 (4) ◽  
pp. 475-482
Author(s):  
Yu Kamada ◽  
◽  
Jiwang Yan
Keyword(s):  
Polymer Composites ◽  
Feed Rate ◽  
Surface Defects ◽  
Cutting Temperature ◽  
Cutting Speed ◽  
Chip Morphology ◽  
Diamond Turning ◽  
Cellulose Nanofiber ◽  
Machined Surface ◽  
Reinforced Polymer

Cellulose nanofiber (CeNF)-reinforced polymer composites have wide potential applications in the manufacturing of optical and mechanical parts owing to their light weight, high mechanical strength, and optical transparency. In this study, CeNF-reinforced homogeneous polypropylene (PP-CeNF) was machined under various conditions by ultraprecision diamond turning, and the results were compared with those of pure PP without CeNF addition. The influence of CeNFs on material removal was investigated by examining the surface topography, chip morphology, cutting forces, and cutting temperature. It was found that the surface defects in pure PP cutting were surface tearing, while the surface defects of PP-CeNF were surface tearing and micro-holes induced by the pulling-outs of CeNFs. Surface tearing increased with cutting speed; pulling-outs of CeNFs were slightly affected by cutting speed but strongly dependent on the tool feed rate. Under a small tool feed rate, the surface roughness could be reduced to ∼10 nm Ra for PP-CeNF. The thermal effect was insignificant in the experiments, whereas the effect of strain rate-induced material hardening was dominant for both workpiece materials at a high cutting speed. This study helps to understand the mechanisms for ultraprecision cutting of CeNF-reinforced polymer composites and provides guidelines for improving the machined surface quality.

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