A Comparison of Flame Coating and Laser Cladding Using Ni Based Powders

2016 ◽  
Vol 254 ◽  
pp. 77-82 ◽  
Author(s):  
Alexandru Pascu ◽  
Iosif Hulka ◽  
Mircea Horia Tierean ◽  
Catalin Croitoru ◽  
Elena Manuela Stanciu ◽  
...  
Keyword(s):  
Laser Cladding ◽  
Base Material ◽  
Spray Coating ◽  
High Hardness ◽  
Experimental Tests ◽  
Thermal Spray Coating ◽  
High Porosity ◽  
Advantages And Disadvantages ◽  
Flame Coating

This paper addresses to the characterization of Ni based coatings realized by two different processes e.g. thermal spray coating and laser cladding. For the relevance of the experimental tests, the same base material, AISI 5140 and Metco 15E powder was used. The results highlight the advantages and disadvantages of the both techniques. The cladded layer obtained through laser cladding is pore and crack free, being characterized by a high hardness and a very good adherence to the substrate, while the flame coating presents oxides inclusions, high porosity, lower hardness and minimal dilution with the substrate as resulted from the EDS analyses. In depth characterization of the samples is made using optical and scanning electron microscopy, EDS analysis and microhardness testing.

Surface Modification and Repair for Aircraft Life Enhancement and Structural Restoration

2010 ◽  
Vol 654-656 ◽  
pp. 763-766 ◽  
Author(s):  
Qian Chu Liu ◽  
Pud Baburamani ◽  
Wyman Zhuang ◽  
Darrem Gerrard ◽  
Bruce Hinton ◽  
...  
Keyword(s):  
Surface Modification ◽  
Cold Spray ◽  
Laser Cladding ◽  
Particle Deposition ◽  
Research Work ◽  
Spray Coating ◽  
Rolling Friction ◽  
Scientific Management ◽  
Friction Stir ◽  
Advantages And Disadvantages

Maintenance of ageing military aircraft structures encompasses both engineering and scientific management. In support of this, surface modification and repair methods are used on an opportunity basis to extend the life of aircraft in terms of fatigue and safety. Often, certain surface modification technologies have proved to be both cost effective and amenable for safe application. Some candidate technologies include shot peening, cold spray, deep surface rolling, friction stir welding, laser shock peening, and laser cladding. Whilst some technologies have been successfully applied to Australian Defence Force (ADF) aircraft in the past, some newer technologies are also being considered. The supersonic particle deposition (SPD) technology also known as cold spray coating has been recently approved for application on a helicopter gear box. Another technology of significance to ADF application is Laser Cladding (LC) technology. This paper briefly summarises the research work on these technologies at DSTO and discusses potential applications for aircraft components in the near future. It also provides an analysis of technologies and their potential advantages and disadvantages.

High Porosity Thermal Spray Coating: Development, Characterization, and Friction Evaluation

2021 ◽  
Author(s):  
Arup Gangopadhyay ◽  
Cliff E. Maki ◽  
Zak Liu ◽  
Robert J. Zdrodowski ◽  
Larry D. Elie
Keyword(s):  
Thermal Spray ◽  
Spray Coating ◽  
Thermal Spray Coating ◽  
High Porosity

Tribo Mechanical Properties of CoCr and NiWCrB Hardfacing Superalloy Coating Systems

2014 ◽  
Author(s):  
M. Azzi ◽  
L. Vernhes ◽  
E. Bousser ◽  
J. E. Klemberg-Sapieha
Keyword(s):  
Wear Resistance ◽  
Thermal Spray ◽  
Microstructural Analysis ◽  
Spray Coating ◽  
High Hardness ◽  
Thermal Spray Coating ◽  
Hard Coatings ◽  
Corrosion Properties ◽  
Cross Sectional ◽  
Indentation Technique

Wear of materials is a serious problem facing industry especially in mechanical applications where moving parts are continuously subjected to friction. Hard coatings prepared by a variety of processes are nowadays considered as effective solutions to protect components against wear. Examples of such processes are: thermal spray coating, vacuum-based coating and hardfacing. In this paper, we study the mechanical, tribological and corrosion properties of two hard coating systems: CoCr Stellite 6 (ST6) hardfacing on 316 stainless steel and NiWCrB Colmonoy 88 (C88) thermal spray coating on Inconel 718. The effect of gas nitriding on the microstructure and wear performance of these coating systems is investigated. X-ray diffraction, energy dispersive spectroscopy and scanning electron microscopy were used for microstructural analysis. Micro-indentation technique was utilized to measure the surface and cross-sectional hardness of the coatings. Rockwell indentation technique was used to evaluate coating adhesion in accordance with CEN/TS 1071-8. Pin-on-disk tests were conducted to assess the tribological performance of the coatings. Microstructural analysis showed that ST6 has a cobalt matrix in the form of dendrites reinforced with metal carbide particles whereas C88 has a Nickel matrix reinforced mainly with metal boride particles. ST6 and C88 improved significantly the wear resistance of their corresponding substrates. This is mainly due to good adhesion and high hardness of the coatings; HR15N values of ST6 and C88 were almost 85 as compared to 61 and 80 for 316 and INC substrates, respectively. ST6 was found to improve significantly the corrosion resistance of 316 whereas C88 decreased the corrosion performance of INC. Moreover, nitriding treatment was found to improve significantly the wear resistance of 316 and INC, however, in the case of ST6, nitriding was beneficial in terms of wear resistance only at relatively low load.

Study on Cutting Hard Thermal Spray Coating

2011 ◽  
Vol 101-102 ◽  
pp. 974-977
Author(s):  
Zhi Yuan Wu ◽  
Xiao Jun Shi ◽  
Xin Li Tian ◽  
Xiu Jian Tang ◽  
Shu Zhang
Keyword(s):  
Experimental Investigation ◽  
Thermal Spray ◽  
Surface Finish ◽  
Spray Coating ◽  
High Hardness ◽  
Thermal Spray Coating ◽  
Cutting Process ◽  
Creep Feed ◽  
Huge Impact

The CBN and YG610 were used for remanufacture thermal spray coating cutting. The feed rates, in the experiment, adopt mode of creep feed. The experiment results showed that the YG610 can cut the thermal spray coating efficiently. And the surface finish qualities are all under Ra1, which can come up to the standard of common grinding. But the CBN tools will be broken in the cutting process, though it can perform well in the evenly qualitative material. By experimental investigation and analyses, it can be conclude that both the high hardness and huge impact exist in cutting process, which are main reasons which induce tools broken. So the materials of tools for cutting thermal spray coating need possess both sufficient hardness and toughness.

scholarly journals Manufactural Investigations on Dissimilar Laser Cladding and Post-Clad Heat Treatment Processes of Heat-Resistant Ni Alloy on Cu Substrate

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 993
Author(s):  
Eun-Joon Chun
Keyword(s):  
Heat Treatment ◽  
Continuous Casting ◽  
Laser Cladding ◽  
Thermal Spraying ◽  
Spray Coating ◽  
Thermal Spray Coating ◽  
Secondary Phases ◽  
Continuous Casting Mold ◽  
Cu Substrate ◽  
High Durability

Hardness of dissimilar laser clad samples of NiCrBSi alloy on a Cu substrate was investigated, with the aim of optimizing the manufacturing process for high-durability continuous casting molds for steelmaking. The performance of the clads is compared with that of samples prepared by thermal spray coating, and an optimal process is proposed. Dissimilar laser cladding between NiCrBSi alloy and Cu was achieved with a hardness of ~450 HV using a high-power diode laser, and no cracks and pores were observed. Post-clad heat treatment performed below the melting point of the Cu substrate (1357 K) using a furnace (1223 K for 500 min) resulted in a decrease in the hardness to 142 HV, which was attributed to the dilution of the alloy with the soft Cu substrate and changes to the microstructure; the solidification microstructure was almost homogenized during the heat treatment, and secondary boride phases were formed and almost dissolved in the matrix phase. Laser surface heat treatment of the clad metal at 1323 K resulted in a decrease in the hardness (to 359 HV near the surface), with a heat treatment depth of ~1.3 mm. In contrast, the hardness of the as-sprayed coatings was 730–750 HV, which drastically increased to ~1200 HV after laser fusing because of the formation of finely distributed secondary phases. Therefore, to achieve high-durability continuous casting mold components, minimization of Cu dilution is preferentially recommended for the laser cladding of NiCrBSi alloy on Cu substrate. Furthermore, when it is difficult to minimize the Cu dilution during the laser cladding, thermal spraying in conjunction with laser fusing treatment appears to be sufficiently applicable for high-durability continuous casting molds.

352 Characterization of Thermal Spray Coating for the Piston

2014 ◽  
Vol 2014 (0) ◽  
pp. 71-72
Author(s):  
Masashi SEKINE ◽  
Toshiki ASAKAWA ◽  
Keiji SONOYA ◽  
Masanobu NAKAMURA
Keyword(s):  
Thermal Spray ◽  
Spray Coating ◽  
Thermal Spray Coating

Interfacial Elemental Distribution In Tungsten Carbide Coated Steel

1999 ◽  
Vol 5 (S2) ◽  
pp. 838-839
Author(s):  
S.V. Naidu ◽  
Carlos Green ◽  
Christopher Maxie ◽  
James D. Garber ◽  
Gary A. Glass
Keyword(s):  
Thermal Spray ◽  
Steel Substrate ◽  
Spray Coating ◽  
High Hardness ◽  
Thermal Spray Coating ◽  
Elemental Distribution ◽  
Coated Steel ◽  
X Ray ◽  
Carbide Coatings ◽  
Steel Substrates

Thermal spray of carbide coatings with high hardness and corrosion resistance onto steel substrates has technological importance. The adhesive strength is greatly effected by the interfacial impurities. Low porous and good quality 200 μm thick 86WC10Co4Cr coatings on 4140 steel are obtained by thermal spray methods using SC-HVOF gun at Cooper Oil Tools, Houston, TX. A Carl Zeiss DSM942 SEM with 3.5 nm resolution at 30 keV and Kevex LPX1 Super Dry Quantum Si(Li) Detector with < 145 eV resolution for Energy Dispersive X-ray Spectroscopy (EDXS) were used to study the elemental distribution across the interface. Fig. 1 shows the SEM micrographs of the interface between 86WC10Co4Cr thermal spray coating and 4140 steel substrate. The anchor patterns seen at the interface are believed to improve the adhesive qualities between the coating and the substrate.

Implantable neural interfaces

2018 ◽  
Author(s):  
Stefano Vassanelli
Keyword(s):  
Brain Function ◽  
Large Scale ◽  
Ionic Channels ◽  
Patch Clamp Technique ◽  
Advantages And Disadvantages ◽  
Optogenetic Stimulation ◽  
Physical Interfaces ◽  
The Brain

Establishing direct communication with the brain through physical interfaces is a fundamental strategy to investigate brain function. Starting with the patch-clamp technique in the seventies, neuroscience has moved from detailed characterization of ionic channels to the analysis of single neurons and, more recently, microcircuits in brain neuronal networks. Development of new biohybrid probes with electrodes for recording and stimulating neurons in the living animal is a natural consequence of this trend. The recent introduction of optogenetic stimulation and advanced high-resolution large-scale electrical recording approaches demonstrates this need. Brain implants for real-time neurophysiology are also opening new avenues for neuroprosthetics to restore brain function after injury or in neurological disorders. This chapter provides an overview on existing and emergent neurophysiology technologies with particular focus on those intended to interface neuronal microcircuits in vivo. Chemical, electrical, and optogenetic-based interfaces are presented, with an analysis of advantages and disadvantages of the different technical approaches.

Sign in / Sign up

Export Citation Format

Share Document