INVESTIGATION OF SOTS AND AMO IMPACT UPON THREAD-CUTTING  RELIABILITY IN ULTRA-SMALL HOLES

The purpose of this work consists in the reliability increase of thread cutting with the use of tap borers in super-small holes of aluminum alloy parts. The investigation methods used are based on classic regulations of the cutting theory, physical-chemical mechanics of materials, reliability theory and methods of statistical analysis. There are revealed the reasons of thread cutting low reliability and tool failure. The effectiveness of edge anode-machining use at thread cutting is researched. On the basis of data obtained there is carried out a calculation of basic indices of thread cutting reliability. A comparative analysis of the processing reliability indices obtained under standard conditions and with the use of the developed circuit of anode-machining is shown, the effectiveness of the latter use is presented. As a result of the investigations carried out there is developed a technology for thread cutting in super-small holes that ensures a considerable increase of reliability and allows excluding hand work during the process.

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Peculiarities of chip piling in tap chip grooves during thread-cutting in ultra-small holes

Science intensive technologies in mechanical engineering ◽

10.30987/article_5c90a5975f16e2.52962755 ◽

2019 ◽

Vol 2019 (4) ◽

pp. 26-30

Author(s):

Максим Ягодкин ◽

Maksim Yagodkin

Keyword(s):

Cutting Process ◽

Cutting Condition ◽

Thread Cutting ◽

Chip Removal ◽

Small Holes

There is considered a thread-cutting process in ultra-small holes. It is revealed that cutting condition toughening arises because of the chip removal complexity and impossibility of chip complete filing in consequence of insufficient chip grooves volume.

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Stereo Electron Microscopy Applied to High Resolution Freeze-Etch Replicas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068527 ◽

1970 ◽

Vol 28 ◽

pp. 306-307

Author(s):

L. Andrew Staehelin

Keyword(s):

Electron Microscopy ◽

Plastic Deformation ◽

High Resolution ◽

Smooth Surfaces ◽

Small Particles ◽

Membrane Surfaces ◽

Wide Acceptance ◽

New Information ◽

Number Of Particles ◽

Small Holes

Freeze-etched membranes usually appear as relatively smooth surfaces covered with numerous small particles and a few small holes (Fig. 1). In 1966 Branton (1“) suggested that these surfaces represent split inner mem¬brane faces and not true external membrane surfaces. His theory has now gained wide acceptance partly due to new information obtained from double replicas of freeze-cleaved specimens (2,3) and from freeze-etch experi¬ments with surface labeled membranes (4). While theses studies have fur¬ther substantiated the basic idea of membrane splitting and have shown clearly which membrane faces are complementary to each other, they have left the question open, why the replicated membrane faces usually exhibit con¬siderably fewer holes than particles. According to Branton's theory the number of holes should on the average equal the number of particles. The absence of these holes can be explained in either of two ways: a) it is possible that no holes are formed during the cleaving process e.g. due to plastic deformation (5); b) holes may arise during the cleaving process but remain undetected because of inadequate replication and microscope techniques.

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Influence of the choice of wear criterion on the life of high speed machine manual taps

10.36652/0042-4633-2020-7-74-78 ◽

2020 ◽

pp. 74-78

Author(s):

A.E. Dreval

Keyword(s):

Service Life ◽

Structural Steel ◽

Tool Life ◽

High Speed ◽

High Speed Steel ◽

Parameter Dependence ◽

Limiting State ◽

Thread Cutting ◽

Failure Life ◽

High Speed Machine

The assessment of the limiting state of high-speed machine-manual taps in the processing of structural steel billets is considered. A general multi-parameter dependence is developed for calculating the criterion of allowable wear, which makes it possible to rationally use the tool life and normalize the cut amount during regrinding. Keywords thread cutting, tap, angle of the cutting part, criterion, high-speed steel, wear, failure, life, service life. [email protected]

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Study of ultrasonic vibration–assisted thread turning of Inconel 718 superalloy

Advances in Mechanical Engineering ◽

10.1177/1687814019883772 ◽

2019 ◽

Vol 11 (10) ◽

pp. 168781401988377

Author(s):

Yu He ◽

Zhongming Zhou ◽

Ping Zou ◽

Xiaogang Gao ◽

Kornel F Ehmann

Keyword(s):

Surface Quality ◽

Ultrasonic Vibration ◽

Inconel 718 ◽

Gas Turbines ◽

Tool Path ◽

Machining Parameters ◽

Thread Cutting ◽

Workpiece Surface ◽

Inconel 718 Superalloy ◽

The Relationship

With excellent properties, high-temperature superalloys have become the main application materials for aircraft engines, gas turbines, and many other devices. However, superalloys are typically difficult to machine, especially for the thread cutting. In this article, an ultrasonic vibration–assisted turning system is proposed for thread cutting operations in superalloys. A theoretical analysis of ultrasonic vibration–assisted thread cutting is carried out. An ultrasonic vibration–assisted system was integrated into a standard lathe to demonstrate thread turning in Inconel 718 superalloy. The influence of ultrasonic vibration–assisted machining on workpiece surface quality, chip shape, and tool wear was analyzed. The relationship between machining parameters and ultrasonic vibration–assisted processing performance was also explored. By analyzing the motion relationship between tool path and workpiece surface, the reasons for improved workpiece surface quality by ultrasonic vibration–assisted machining were explained.

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Critical conditions for organic thread cutting under electric fields

Soft Matter ◽

10.1039/d0sm02078h ◽

2021 ◽

Author(s):

Shuai Yin ◽

Yi Huang ◽

Teck Neng Wong

Keyword(s):

Electric Fields ◽

Capillary Number ◽

Critical Conditions ◽

Thread Cutting ◽

On Demand

Critical conditions with electric capillary number are investigated for triggering the on-demand cutting of an organic thread in a microchannel under electric fields.

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Analysis of Multi-Physics Coupling of Small Holes in GH4169 Alloy by Electrolytic Processing of Tube Electrodes

Micromachines ◽

10.3390/mi12070828 ◽

2021 ◽

Vol 12 (7) ◽

pp. 828

Author(s):

Zhaolong Li ◽

Ye Dai

Keyword(s):

Oxide Layer ◽

Small Hole ◽

Machining Accuracy ◽

Tool Electrode ◽

Metallic Oxide ◽

Power Sources ◽

Processing Stability ◽

Hole Structure ◽

Gh4169 Alloy ◽

Small Holes

This paper presents a simulation and experimental study of the structure of small holes in GH4169 alloy electrolytic ally processed by tube electrodes with different characteristic power sources. It analyzes the multi-physical field coupling relationship of flow, temperature, and electric fields within the interstitial space. The results indicate that the tube electrode electrolytic processing of the GH4169 alloy small hole structure with a pulsed power supply has more uniform temperature and current density distribution within the gap, which is beneficial to the processing accuracy and smoothness of the small hole structure. Meanwhile, SEM was used to analyze the microscopic morphology of the electrode end surface during short-circuiting, and it was concluded that as the processing continued, the electrode end surface gradually produced a non-metallic oxide layer, which destroyed the electric field of the gap and affected the processing stability. The use of high-frequency positive and negative pulse power can effectively avoid the generation of a non-metallic oxide layer. Through the combination of simulation analysis and experimental verification, it is concluded that increasing electrolyte pressure in stages can effectively improve machining accuracy and stability. The interstitial current increases as the feed rate of the tool electrode increases, and the diameter of the machined small hole decreases as it increases.

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