High-speed deposition of functional composite thick coating using cold spray

2019 ◽  
Vol 2019.27 (0) ◽  
pp. 205
Author(s):  
Jongbeom Choi ◽  
Nana Okimura ◽  
Wataru Nakayama ◽  
Takuya Hotchi ◽  
Yuki Hirata ◽  
...  
Keyword(s):  
Cold Spray ◽  
High Speed ◽  
Functional Composite ◽  
Thick Coating

scholarly journals Microstructure, Mechanical Properties and Corrosion Behavior of the Aluminum Alloy Components Repaired by Cold Spray with Al-Based Powders

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1633
Author(s):  
Zhiyi Zhang ◽  
Xiaoguang Sun ◽  
Shiming Huang ◽  
Xiaohui Han ◽  
Ping Zhu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Cold Spray ◽  
Corrosion Behavior ◽  
High Speed ◽  
Neutral Salt ◽  
Cold Spray Process ◽  
Spray Process ◽  
High Speed Trains ◽  
Mechanical Properties And Corrosion

Aluminum alloy components of high-speed trains have a great risk of being corroded by various corrosive medium due to extremely complex atmospheric environments. This will bring out huge losses and reduce the safety and stability of trains. In order to solve the problem, cold spray process was used for repairing the damage of the aluminum alloy components with Al-based powders. Microstructure, mechanical properties and corrosion behavior were studied. The results indicated that there were very few pores and cracks in the repaired areas after repairing. The average microhardness of the repaired areas was 54.5 HV ± 3.4 HV, and the tensile strength of the repaired samples was 160.4 MPa. After neutral salt spray tests for 1000 h, the rate of mass loss of the samples repaired by cold spray was lower than that of 6A01 aluminum alloy. The electrochemical test results showed that the repaired areas had a higher open circuit potential than 6A01 aluminum alloy. As a result, the repaired areas such as the anode protected its nearby substrate. The samples repaired by cold spray exhibited better corrosion than 6A01 aluminum alloy. Cold spray process and Al-based powders are applicable for repairing the aluminum alloy components of high-speed trains.

Numerical Simulation of the Cold Spray Deposition Process for Aluminium and Copper

2012 ◽  
Author(s):  
Jing Xie ◽  
Daniel Nelias ◽  
Hélène Walter-le Berre ◽  
Yuji Ichikawa ◽  
Kazuhiro Ogawa
Keyword(s):  
Reference Frame ◽  
Cold Spray ◽  
High Speed ◽  
Gas Flow ◽  
Heat Dissipation ◽  
Spray Deposition ◽  
Deposition Process ◽  
Arbitrary Lagrangian Eulerian ◽  
Systematic Analysis ◽  
The Impact

Cold spray is a rapidly developing coating technology for depositing materials in the solid state. In this deposition process, the spray particles are accelerated to a high velocity by a high-speed gas flow, and then form a dense and high quality coating due to plastic deformation of particles impinged upon the solid surface of substrate. 2D and 3D modelling of particle impacting behaviours in cold spray deposition process by using ABAQUS/Explicit was conducted for four couples of materials (i.e. impacting particle/impacted substrate): copper/aluminium, aluminium/copper, copper/copper, and aluminium/aluminium. A systematic analysis of a single impact was carried out considering different parameters, such as the initial impact velocity, initial temperature and contact angle, which affect the deposition process and subsequently the mechanical properties of coating. Three numerical methods have been evaluated and their performances are discussed for various simulation settings: (i) modelling in a Lagrangian reference frame; (ii) modelling using adaptive remeshing in an Arbitrary Lagrangian Eulerian (ALE) reference frame; and (iii), modelling in a CEL reference frame. It is found that the Coupled Eulerian Lagrangian (CEL) method has more advantages to simulate the large deformation of materials, and is also more efficient to prevent the excessive distortion of the mesh. A comparison between simulation results and experimental data from the literature was performed. Nevertheless, the CEL method is implicitly isothermal for ABAQUS v6.10, whereas the modelling in the classical Lagrangian reference frame does include coupled thermo-mechanical effects with a local increase of the temperature near the interface — due to friction — and for the highly plastically deformed elements — due to the heat dissipation linked to plasticity. A local rise of temperature at the impact surface may also be observed for oblique impacts. Finally a first attempt to simulate the deposition of several particles is made with a 3D CEL model, resulting in the creation of porosity at the interface between particles.

Combined Laser Shock and Micro-Compression Approach to the Mechanical Behavior of Powders for Cold Spray

2021 ◽  
Author(s):  
H. Durand ◽  
L. Lacourt ◽  
J.-C. Teissedre ◽  
F. Delloro ◽  
A. Thorel ◽  
...  
Keyword(s):  
Mechanical Behavior ◽  
Cold Spray ◽  
High Speed ◽  
Fem Simulation ◽  
Material Behavior ◽  
Laser Shock ◽  
High Speed Imaging ◽  
Spray Process ◽  
Before And After ◽  
Cook Model

Abstract In cold spray, particles undergo large plastic deformation upon impact in a rapid dynamic regime (up to 109 s-1) at solid state. The simulation of this impact is key to understanding the cold spray process. In this study, an approach based on laser shock and micro-compression testing was developed to characterize the mechanical behavior of powders and fit parameters of the Johnson-Cook material behavior model. In situ micro-compression particle testing was performed in a SEM equipped with a microindentation stage. From subsequent FEM simulations of the test, static coefficients of the Johnson-Cook model were identified. A laser shock powder launcher (LASHPOL) was also developed to accelerate single particles and measure their corresponding velocity using high-speed imaging. In addition, image analysis of the particles before and after impact, together with FEM simulation, were used to determine strain rate hardening coefficients for the Johnson-Cook model.

Residual Stress Characterization From Numerical Analysis of the Multi-Particle Impact Behavior in Cold Spray

2017 ◽  
Author(s):  
Kando Hamiyanze Moonga ◽  
Tien-Chien Jen
Keyword(s):  
Residual Stress ◽  
Numerical Analysis ◽  
Compressive Stress ◽  
Cold Spray ◽  
High Speed ◽  
Compressive Residual Stress ◽  
Impact Behavior ◽  
Particle Impact ◽  
Cold Spray Process ◽  
Spray Process

In cold spray, bonding forms between a substrate and the particles and between particles through impact deformation at high strain rates. A prominent feature of the cold spray process is the compressive residual stress that arises during the deposition process. Compressive residual stress on the surface can be beneficial for fatigue resistance. As a post processing technique several applications require surface treatment processes that produce this state of stress on component surfaces such as shot peening, laser shock peening, ultrasonic impact treatment, low plasticity burnishing, etc. In all of these methods, the compressive stress is produced through plastic deformation of the surface region. In a similar manner, the cold spray process induces compressive stress by high speed impact of the sprayed particles on the surface, causing a peening effect. The effects of these variations in the properties of the coatings are rarely reported. Moreover, there are some applications which require minimal residual stresses in the components such as in optics. In this study, we have investigated the residual stress using numerical analysis of the multi-particle impact behavior in cold spray.

Investigation of Cold Sprayed NiCoCrAlY Bond Coating

2009 ◽  
Vol 79-82 ◽  
pp. 863-866 ◽  
Author(s):  
Xiang Bo Li
Keyword(s):  
Cold Spray ◽  
High Speed ◽  
Cold Spraying ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Cross Sectional ◽  
Bond Coating ◽  
Spray Process ◽  
High Speed Impact ◽  
Helium Gas

In this paper, NiCoCrAlY coating was deposited by cold spraying with helium gas under the temperature of 500°C and pressure of 2.6 MPa. The microstructure of the coating was characterized through surface morphology and cross-sectional microstructure by scanning electron microscopy and X-ray diffraction analysis. The results showed that the coating is deposited through intensive plastic deformation of the spray particles by high-speed impact, and no oxygen phenomena discovered in the cold spray process. We also detected the micro-hardness using the Digital Vickers Microhardness Tester. Result revealed that a compact texture and high micro-hardness NiCoCrAlY coating can be obtained by cold spray.

scholarly journals EELS of the Interface between Al and Glass Formed with a High Speed Collision Process of Cold Spray

2018 ◽  
Vol 24 (S1) ◽  
pp. 468-469
Author(s):  
Minghui Song ◽  
Hiroshi Araki ◽  
Seiji Kuroda ◽  
Kazuhiko Sakaki
Keyword(s):  
Cold Spray ◽  
High Speed ◽  
Collision Process ◽  
High Speed Collision

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

Sign in / Sign up

Export Citation Format

Share Document