Adhesive-wear failure mechanisms in single asperity junctions

The failure progression of coated carbide tools in end milling of Inconel 718 superalloy was investigated. Tool wear was measured and failure mechanisms were discussed in the experimental process periodically. The experimental results indicated that the tool failure mechanisms were synergistic interaction among abrasive wear, adhesive wear, and fatigue wear. However, abrasive wear and adhesive wear were the main failure mechanisms at the beginning, fatigue wear prevailed the upper hand around the time when edge chipping appeared, and after edge chipping abrasive wear and adhesive wear dominated until the failure time. In addition, the macroscopic failure of the cutting tools is closely correlated to the nucleation and propagation of the crack under cyclic mechanical and thermal impact forces. Mechanical fatigue wear was the key form of fatigue wear at lower cutting speed, while at higher cutting speed thermal fatigue wear was the dominant fatigue wear.

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A General Model for Microelastohydrodynamic Lubrication and Its Full Numerical Solution

Journal of Tribology ◽

10.1115/1.3261979 ◽

1989 ◽

Vol 111 (4) ◽

pp. 569-576 ◽

Cited By ~ 31

Author(s):

Xiaolan Ai ◽

Linqing Zheng

Keyword(s):

Thin Film ◽

General Model ◽

Failure Mechanisms ◽

Thin Film Lubrication ◽

Transient Model ◽

Single Asperity ◽

Physical Features ◽

Relaxation Iteration ◽

Film Lubrication ◽

Ehl Contact

A general transient model for microelastohydrodynamic lubrication with Eyring fluid was established in this paper to describe the basic processes involved in thin film lubrication with rough surfaces, namely the process of a single asperity when it passes through the macro-EHL contact with or without sliding, and the process for a pair of asperities when they collide under macro-EHL pressure ambient. The solution of this model was performed by a relaxation iteration method that had been found to be simple and effective. Results showed some physical features that were previously unknown, and provided information to unlock the mysteries of several important failure mechanisms in lubricated concentrated contacts.

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Adhesive wear law at the single asperity level

Journal of the Mechanics and Physics of Solids ◽

10.1016/j.jmps.2020.104069 ◽

2020 ◽

Vol 143 ◽

pp. 104069 ◽

Cited By ~ 2

Author(s):

Kai Zhao ◽

Ramin Aghababaei

Keyword(s):

Adhesive Wear ◽

Single Asperity ◽

Wear Law

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Self-Sharpening Failure Characteristic of a Si3N4 Ceramic Tool in High Speed Cutting of Inconel 718

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.693.1135 ◽

2016 ◽

Vol 693 ◽

pp. 1135-1142 ◽

Cited By ~ 1

Author(s):

Guang Ming Zheng ◽

Jun Zhao ◽

Xiang Cheng ◽

Min Wang

Keyword(s):

Inconel 718 ◽

High Speed ◽

Adhesive Wear ◽

Failure Mechanisms ◽

Cutting Edge ◽

Ceramic Tool ◽

Tool Failure ◽

High Speed Cutting ◽

Failure Characteristic ◽

Failure Evolution

A Si3N4 ceramic tool material with high mechanical properties was fabricated by hot-pressing sintering process. The high speed machining of Inconel 718 tests were carried out with round ceramic inserts. The failure surface and microstructure were analyzed by scanning electron microscopy (SEM) to reveal the ceramic tool failure mechanisms. The results showed that the main failure mechanisms of the Si3N4 ceramic tool were flaking, micro-chipping, abrasive wear and adhesive wear in the turning process. On the other hand, chipping, flaking and adhesive wear were the main failure reasons in the milling process. Meanwhile, some small flaking along the cutting edge and step-shaped flaking on the rake face closed to the cutting edge were found on the failure surfaces, which was a typical self-sharpening failure characteristic of the ceramic tool in the high-speed cutting process. This tool failure evolution characteristic of the ceramic tool can be attributed to its higher flexural strength and fracture toughness, which was beneficial to improve the tool life and was constrained by cutting conditions.

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UDDEHOLM VANCRON 40

Alloy Digest ◽

10.31399/asm.ad.ts0687 ◽

2010 ◽

Vol 59 (3) ◽

Keyword(s):

Wear Resistance ◽

North America ◽

Deep Drawing ◽

Adhesive Wear ◽

Cold Work ◽

Failure Mechanisms ◽

Heat Treating ◽

Cold Extrusion ◽

Powder Metal ◽

Powder Pressing

Abstract Uddeholm Vancron 40 offers an excellent combination of galling resistance and adhesive wear resistance, which should be used in cold-work applications where the predominant failure mechanisms are adhesive wear or galling. Typical applications include blanking and forming, cold extrusion, deep drawing, and powder pressing. This datasheet provides information on composition, physical properties, and elasticity. It also includes information on heat treating, machining, surface treatment, and powder metal forms. Filing Code: TS-687. Producer or source: Böhler-Uddeholm North America.

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On the role of tin underlays for the prevention of thermal grooving in thin gold films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145030 ◽

1986 ◽

Vol 44 ◽

pp. 732-733

Author(s):

Jin Young Kim ◽

R. E. Hummel ◽

R. T. DeHoff

Keyword(s):

Thin Film ◽

Free Surface ◽

Grain Boundary ◽

Beneficial Effect ◽

Failure Mechanism ◽

Failure Mechanisms ◽

Distinct Advantage ◽

Gold Films ◽

Gold Thin Film

Gold thin film metallizations in microelectronic circuits have a distinct advantage over those consisting of aluminum because they are less susceptible to electromigration. When electromigration is no longer the principal failure mechanism, other failure mechanisms caused by d.c. stressing might become important. In gold thin-film metallizations, grain boundary grooving is the principal failure mechanism.Previous studies have shown that grain boundary grooving in gold films can be prevented by an indium underlay between the substrate and gold. The beneficial effect of the In/Au composite film is mainly due to roughening of the surface of the gold films, redistribution of indium on the gold films and formation of In2O3 on the free surface and along the grain boundaries of the gold films during air annealing.

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Real-time cryo-deformation of polypropylene and impact-modified polypropylene in the transmission electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100150290 ◽

1993 ◽

Vol 51 ◽

pp. 892-893

Author(s):

Robert C. Cieslinski ◽

H. Craig Silvis ◽

Daniel J. Murray

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Failure Mechanisms ◽

Brittle Transition ◽

Molded Part ◽

Transmission Electron ◽

Solvent Cast ◽

The Impact ◽

Annealed Copper ◽

Dynamic Plane

An understanding of the mechanical behavior polymers in the ductile-brittle transition region will result in materials with improved properties. A technique has been developed that allows the realtime observation of dynamic plane stress failure mechanisms in the transmission electron microscope. With the addition of a cryo-tensile stage, this technique has been extented to -173°C, allowing the observation of deformation during the ductile-brittle transition.The technique makes use of an annealed copper cartridge in which a thin section of bulk polymer specimen is bonded and plastically deformed in tension in the TEM using a screw-driven tensile stage. In contrast to previous deformation studies on solvent-cast films, this technique can examine the frozen-in morphology of a molded part.The deformation behavior of polypropylene and polypropylene impact modified with EPDM (ethylene-propylene diene modified) and PE (polyethylene) rubbers were investigated as function of temperature and the molecular weight of the impact modifier.

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