In situ monitoring of friction surfaces and their sequence pattern analysis

2007 ◽  
Vol 366 (1865) ◽  
pp. 665-671 ◽  
Author(s):  
S Kano ◽  
H Homma ◽  
S Sasaki ◽  
H Shimura
Keyword(s):  
Laser Pulse ◽  
Friction Surface ◽  
Optical Microscope ◽  
Carbon Steels ◽  
In Situ Monitoring ◽  
Plate Motion ◽  
Surface Pattern ◽  
Size And Shape ◽  
Motion Speed ◽  
Friction Surfaces

Friction occurs between solid surfaces, and even sometimes on lubricated surfaces. To understand tribological subjects, it is important to know the changes that occur in friction surfaces. In this study, a laser strobe technique is applied to a friction surface observation. The recorded surface images were analysed using pattern-matching methods and their correlations are discussed. A test using pin-on-plate methods with carbon steels was performed using a reciprocating motion speed of 10 Hz for 4.9 N. A pulsed laser light (Nd:YAG SHG=532 nm, 5 ns per pulse) was irradiated onto the friction surface. It was induced using an optical microscope that was located just to the side of the pin. The laser pulse was synchronized with the plate motion, which was a trigger of the laser pulse. The surface image was stored for every cycle. These sequences were calculated and their correlations were analysed as a function of the surface pattern and the friction track size and shape. Analysis revealed that some groups were distinguishable as parameters of the damage size and shape.

The Influence of Oxide Inclusion on the Refinement of Bainite and Toughness in HAZ for Low Carbon Steels

2013 ◽  
Vol 651 ◽  
pp. 163-167
Author(s):  
Shu Rui Li ◽  
Xue Min Wang ◽  
Xin Lai He
Keyword(s):  
Mechanical Properties ◽  
Acicular Ferrite ◽  
Oxide Inclusion ◽  
Optical Microscope ◽  
Carbon Steels ◽  
Low Carbon ◽  
Low Carbon Steels ◽  
The Core ◽  
Ti Oxides ◽  
Bainitic Steels

The influence of Ti oxide on the toughness of heat affected zone for low carbon bainitic steels has been investigated. The optical microscope, SEM and TEM were used to analyze the composition, size and distribution of the inclusions, and the microstructure and mechanical properties after welding thermal simulation were also investigated. The effect of Ti oxide inclusion on the transformation of acicular ferrite has also been studied. The results show that after the melting with Ti dioxide technique the inclusion is complex, in the core is Ti oxides about 1-3 micron and around it is MnS. It has been found the acicular ferrite can nucleate at the inclusions and the Ti oxide inclusion will promote the nucleation of acicular ferrite, and the acicular ferrite will block the growth of bainite. Therefore by introducing the Ti oxide in the steels the microstructure of HAZ could be refined markedly therefore the toughness of HAZ can be improved evidently.

Atomic Force Microscopy of Annealed Plain Carbon Steels

2015 ◽  
Author(s):  
Surendra Kumar Gupta ◽  
Patricia Iglesias Victoria
Keyword(s):  
Atomic Force Microscopy ◽  
Optical Microscopy ◽  
Interlamellar Spacing ◽  
Lamellar Spacing ◽  
Optical Microscope ◽  
Carbon Steels ◽  
Force Microscopy ◽  
Atomic Force

Microstructure of annealed plain carbon steels is examined using optical microscopy. When the inter-lamellar spacing in pearlite is small, optical microscope at 1000X is unable to resolve the ferrite and cementite lamellae. In hyper-eutectoid steels, cementite in pearlite appears as darker phase whereas the pro-eutectoid cementite appears as a lighter phase. Atomic force microscopy (AFM) of etched steels is able to resolve ferrite and cementite lamellae in pearlite at similar magnifications. Both cementite in pearlite as well as pro-eutectoid cementite appear as raised areas (hills) in AFM images. Interlamellar spacing in pearlite increases with increasing hardenability of steel.

Investigation of the formation of friction surface microgeometry of a wear-resistant coating during friction with a metal counterbody

2021 ◽  
pp. 147-152
Author(s):  
N.F. Struchkov ◽  
G.G. Vinokurov ◽  
O.N. Popov
Keyword(s):  
Statistical Model ◽  
Binomial Distribution ◽  
Friction Surface ◽  
Sliding Friction ◽  
Wear Particles ◽  
Wear Resistant ◽  
Wear Resistant Coatings ◽  
Frictional Interaction ◽  
Surface Microgeometry ◽  
Friction Surfaces

Were is researched the friction surfaces of wear-resistant coatings with modifying additives Al2O3 and metal counterbody made of ShH15 steel, and also reveals the factors that influence the formation of coating microgeometry of surface during sliding friction. A statistical model has been developed based on the binomial distribution of removed wear particles to describe the frictional interaction during friction of the coating with a metal counterbody.

Effect of Ti, Al and Mg Addition on the Impact Toughness of Heat Affected Zone in Low Carbon Steel

2009 ◽  
Vol 79-82 ◽  
pp. 143-146
Author(s):  
Jiang Hua Ma ◽  
Dong Ping Zhan ◽  
Zhou Hua Jiang ◽  
Ji Cheng He
Keyword(s):  
Carbon Steel ◽  
Impact Toughness ◽  
Heat Affected Zone ◽  
Low Carbon Steel ◽  
Optical Microscope ◽  
Carbon Steels ◽  
Low Carbon ◽  
Welding Simulation ◽  
Mg Addition ◽  
The Impact

In order to understand the effects of deoxidizer such as aluminium, titanium and magnesium on the impact toughness of heat affected zone (HAZ), three low carbon steels deoxidized by Ti-Al, Mg and Ti-Mg were obtained. After smelting, forging, rolling and welding simulation, the effects of Al, Ti and Mg addition on the impact toughness of HAZ in low carbon steel were studied. The inclusion characteristics (size, morphology and chemistry) of samples before welding and the fracture pattern of the specimens after the Charpy-type test were respectively analyzed using optical microscope and scanning electron microscopy (SEM). The following results were found. The density of inclusion in Ti-Mg deoxidized steel is bigger than Ti-Al deoxidized steel. The average diameter is decreased for the former than the latter. The addition of Ti-Mg can enhance the impact toughness of the HAZ after welding simulation. The maximal value of the impact toughness is 66.5J/cm2. The complex particles of MgO-TiOx-SiO2-MnS are most benefit to enhance impact toughness. The improvement of HAZ is attributable to the role of particle pinning and the formation of intergranular ferrite.

scholarly journals In-Situ Monitoring and Analysis of the Pitting Corrosion of Carbon Steel by Acoustic Emission

2019 ◽  
Vol 9 (4) ◽  
pp. 706 ◽  
Author(s):  
Junlei Tang ◽  
Junyang Li ◽  
Hu Wang ◽  
Yingying Wang ◽  
Geng Chen
Keyword(s):  
Acoustic Emission ◽  
Carbon Steel ◽  
Pitting Corrosion ◽  
Optical Microscope ◽  
Open Circuit ◽  
In Situ Monitoring ◽  
Localized Corrosion ◽  
Uniform Corrosion ◽  
Corrosion Morphology

The acoustic emission (AE) technique was applied to monitor the pitting corrosion of carbon steel in NaHCO3 + NaCl solutions. The open circuit potential (OCP) measurement and corrosion morphology in-situ capturing using an optical microscope were conducted during AE monitoring. The corrosion micromorphology was characterized with a scanning electron microscope (SEM). The propagation behavior and AE features of natural pitting on carbon steel were investigated. After completion of the signal processing, including pre-treatment, shape preserving interpolation, and denoising, for raw AE waveforms, three types of AE signals were classified in the correlation diagrams of the new waveform parameters. Finally, a 2D pattern recognition method was established to calculate the similarity of different continuous AE graphics, which is quite effective to distinguish the localized corrosion from uniform corrosion.

scholarly journals 316L Stainless Steel Powders for Additive Manufacturing: Relationships of Powder Rheology, Size, Size Distribution to Part Properties

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5537
Author(s):  
Robert Groarke ◽  
Cyril Danilenkoff ◽  
Sara Karam ◽  
Eanna McCarthy ◽  
Bastien Michel ◽  
...  
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Additive Manufacturing ◽  
Optical Microscope ◽  
Stainless Steel 316L ◽  
Powder Morphology ◽  
Size And Shape ◽  
Powder Rheology ◽  
Powder Properties ◽  
Particle Size And Shape

Laser-Powder Bed Fusion (L-PBF) of metallic parts is a highly multivariate process. An understanding of powder feedstock properties is critical to ensure part quality. In this paper, a detailed examination of two commercial stainless steel 316L powders produced using the gas atomization process is presented. In particular, the effects of the powder properties (particle size and shape) on the powder rheology were examined. The results presented suggest that the powder properties strongly influence the powder rheology and are important factors in the selection of suitable powder for use in an additive manufacturing (AM) process. Both of the powders exhibited a strong correlation between the particle size and shape parameters and the powder rheology. Optical microscope images of melt pools of parts printed using the powders in an L-PBF machine are presented, which demonstrated further the significance of the powder morphology parameters on resulting part microstructures.

Comparison of Double-Shearing and Coaxial Models for Pressure-Dependent Plastic Flow at Frictional Boundaries

2003 ◽  
Vol 70 (2) ◽  
pp. 212-219 ◽  
Author(s):  
S. Alexandrov
Keyword(s):  
Channel Flow ◽  
Friction Surface ◽  
Qualitative Difference ◽  
Strain Rate Tensor ◽  
Parallel Plates ◽  
Maximum Friction ◽  
Classical Plasticity ◽  
Pressure Independent ◽  
Pressure Dependent Plasticity ◽  
Friction Surfaces

The qualitative difference in solution behavior in the vicinity of maximum friction surfaces is demonstrated for two distinct models of pressure-dependent plasticity (the double-shearing and coaxial models) using closed-form solutions for planar flow through an infinite wedge-shaped channel and plane-strain compression of an infinite block between parallel plates. Singular velocity fields (some components of the strain rate tensor approach infinity at the friction surface) occur in the solutions based on the double-shearing model. This is similar to behavior in the vicinity of maximum friction surfaces in classical plasticity of pressure-independent materials. A singular velocity field is also obtained in the solution based on the coaxial model for the problem of channel flow; but, in contrast to the double-shearing model and classical plasticity, sticking must occur at this friction surface. For the problem of compression of a material obeying the coaxial model, no solution based on conventional assumptions exists with the maximum friction law. This is quite different from both the corresponding solution based on the double-shearing model and the channel flow solution based on the coaxial model.

scholarly journals Technological support of selective transfer on friction surface

2021 ◽  
Vol 2021 (5) ◽  
pp. 35-39
Author(s):  
Viktor Hohlov
Keyword(s):  
Friction Surface ◽  
Selective Transfer ◽  
Roughness Parameters ◽  
Processing Methods ◽  
Technological Support ◽  
Friction Surfaces

Dependences for the computation of roughness parameters and their technological support essential for selective transfer on friction surfaces are offered. Processing methods which should be used for their fulfillment are shown.

Technology of sliding friction surface machining based on hard wear-resistant coating use taking into account technological inheritance impact

2020 ◽  
Vol 2020 (12) ◽  
pp. 31-38
Author(s):  
Tatiana Mihalenko
Keyword(s):  
Wear Resistance ◽  
Friction Surface ◽  
Sliding Friction ◽  
Quality Parameters ◽  
Surface Machining ◽  
Technological Support ◽  
Coating Application ◽  
Technological Inheritance ◽  
Theoretical Investigations ◽  
Friction Surfaces

The matters of technological support of wear-resistance for sliding friction surfaces are considered. The results of experimental theoretical investigations of modes impact of preliminary machining, coating application and sliding friction surfaces finishing upon their quality parameters are shown.

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