Dry Adhesive Friction Process Regularities during Frictional Contact of Heterogeneous “Copper-Aluminum” System Materials

2020 ◽  
Vol 992 ◽  
pp. 785-790
Author(s):  
T.A. Kalashnikova ◽  
Andrey V. Chumaevskii ◽  
A.V. Gusarova

By means of optical and scanning electron microscopy the surface layer structure of aluminum alloy AMg5 samples with introduced copper part after adhesive frictional contact with AISI 420 steel counterbody was studied. It is revealed that under plastic deformation and material fragmentation in the frictional contact zone a complex mixture of different phase layers is formed due to the formation of different flows of aluminum alloy and copper during friction. Mechanical mixing of a material occurs on all length of a friction path with different intensity depending on distance to copper fragment. Both laminar and turbulent flows of material are formed in the surface layer, as well as a wide range of solid solutions, intermetallic phases and mechanical mixtures.

1972 ◽  
Vol 45 (4) ◽  
pp. 1094-1103 ◽  
Author(s):  
G. M. Bartenev ◽  
V. V. Lavrentjev ◽  
N. A. Konstantinova

Abstract Using a specially designed apparatus simultaneous measurements were carried out of the area of contact and the friction between elastomers and solid surfaces. For a wide range of load, the friction force is proportional to the actual contact area and the friction constant depends only on the nature of the rubbing solids. In the range of low sliding velocities the actual contact area remains almost constant. At high sliding velocities increase of the friction force is associated with the process of the mechanical glass-transition of the surface layer of the crosslinked rubber which causes the actual contact area to decrease.


Alloy Digest ◽  
1958 ◽  
Vol 7 (10) ◽  

Abstract AMBRALOY-928 is a copper-aluminum alloy having high strength, hardness and excellent resistance to general corrosion. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength. It also includes information on corrosion resistance as well as forming, machining, and joining. Filing Code: Cu-69. Producer or source: American Brass Company.


2020 ◽  
pp. 200-204
Author(s):  
Yu.S. Semenova ◽  
A.G. Samul’ ◽  
S.V. Mazhuga

Overview of the research results got by various scientific schools in the field of application of ultrasonic surface hardening is provided. Wide range of opportunities of ultrasonic surface hardening is shown for the application in the preliminary machining of surfaces before thermal and chemical treatment, coating, and also as finishing machining. The effect of the energy of ultrasonic vibrations on structure changes in the material of the surface layer and on surface microrelief on parts performance is considered. The prospects of using of the ultrasonic surface hardening method in combination with other methods of the material modification are presented. In addition the possibilities of reducing the manufacturing cost of product by introducing ultrasonic surface hardening into the technological process are shown.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Esteban Gonzalez-Valencia ◽  
Ignacio Del Villar ◽  
Pedro Torres

AbstractWith the goal of ultimate control over the light propagation, photonic crystals currently represent the primary building blocks for novel nanophotonic devices. Bloch surface waves (BSWs) in periodic dielectric multilayer structures with a surface defect is a well-known phenomenon, which implies new opportunities for controlling the light propagation and has many applications in the physical and biological science. However, most of the reported structures based on BSWs require depositing a large number of alternating layers or exploiting a large refractive index (RI) contrast between the materials constituting the multilayer structure, thereby increasing the complexity and costs of manufacturing. The combination of fiber–optic-based platforms with nanotechnology is opening the opportunity for the development of high-performance photonic devices that enhance the light-matter interaction in a strong way compared to other optical platforms. Here, we report a BSW-supporting platform that uses geometrically modified commercial optical fibers such as D-shaped optical fibers, where a few-layer structure is deposited on its flat surface using metal oxides with a moderate difference in RI. In this novel fiber optic platform, BSWs are excited through the evanescent field of the core-guided fundamental mode, which indicates that the structure proposed here can be used as a sensing probe, along with other intrinsic properties of fiber optic sensors, as lightness, multiplexing capacity and easiness of integration in an optical network. As a demonstration, fiber optic BSW excitation is shown to be suitable for measuring RI variations. The designed structure is easy to manufacture and could be adapted to a wide range of applications in the fields of telecommunications, environment, health, and material characterization.


Separations ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 35
Author(s):  
Jason Hoisington ◽  
Jason S. Herrington

A canister-based sampling method along with preconcentrator-Gas chromatography-Mass Spectrometry (GC-MS) analysis was applied to ethylene oxide (EtO or EO) and 75 other volatile organic compounds (VOCs) in ambient air. Ambient air can contain a large variety of VOCs, and thorough analysis requires non-discriminatory sampling and a chromatographic method capable of resolving a complex mixture. Canister collection of whole air samples allows for the collection of a wide range of volatile compounds, while the simultaneous analysis of ethylene oxide and other VOCs allows for faster throughput than separate methods. The method presented is based on US EPA Method TO-15A and allows for the detection of EtO from 18 to 2500 pptv. The method has an average accuracy of 104% and precision of 13% relative standard deviation (RSD), with an instrument run time of 32 min. In addition, a link between canister cleanliness and ethylene oxide growth is observed, and potential mechanisms and cleaning strategies are addressed.


2011 ◽  
Vol 228-229 ◽  
pp. 822-827
Author(s):  
Jia Yuan Luo ◽  
Rong Fan ◽  
Cheng Xiang Shi

Since the aluminum alloy quenching is a complicated and a prompt heat-pressure coupling processing, traditional experimental tests and empirical judgments cannot explain and predict the physical and the force behavior completely during the quenching process. Dynamic simulation of the quenching process is conducted using the finite analysis method. Development laws of the stress and the strain field of the surface layer and core of the alloy during the quenching process are described based on the verification of the simulation. States and process history of the stress and the strain in each phase during the quench are obtained, which provides ponderable data and theoretical value for a fully understanding of the aluminum alloy quenching.


2010 ◽  
Vol 649 ◽  
pp. 101-106
Author(s):  
Mária Svéda ◽  
Dóra Janovszky ◽  
Kinga Tomolya ◽  
Jenő Sólyom ◽  
Zoltán Kálazi ◽  
...  

The aim of our research was to comparatively examine Ni content surface layers on amorphisable Cu base alloy produced by different laser surface treatments. Laser surface treatment (LST) techniques, such as laser surface melting, laser alloying and laser cladding, provide a wide range of interesting solutions for the production of wear and corrosion resistant surfaces. [1,2] With LST techniques, the surface can be: i) coated with a layer of another material by laser cladding, ii) the composition of the matrix can be modified by laser alloying. [3] Two kinds of laser surface treatment technologies were used. In the case of coating-melting technology a Ni content surface layer was first developed by galvanization, and then the Ni content layer was melted together with the matrix. In the case of powder blowing technology Ni3Al powder was blown into the layer melted by laser beam and Argon gas. LST was performed using an impulse mode Nd:YAG laser. The laser power and the interaction time were 2 kW and 20÷60 ms. The characterization of the surface layer microstructure was performed by XRD, scanning electron microscopy and microhardness measurements.


Sign in / Sign up

Export Citation Format

Share Document