Comprehensive Methods for Studying Microinhomogeneity in Thermal Spray Coatings with Amorphous-Crystalline Structure

1998 ◽  
Author(s):  
G. Grigorenko ◽  
A. Borisova
Keyword(s):  
Thermal Spray ◽  
Crystalline Structure ◽  
Structural Phase ◽  
Thermal Spraying ◽  
Integrated Approach ◽  
Thermal Spray Coatings ◽  
Chemical Heterogeneity ◽  
New Approach ◽  
X Ray ◽  
Spray Coatings

Abstract An integrated approach was developed for investigation of thermal spray coatings with the amorphous-crystalline structure. The new approach combines methods of metallography, differential thermal and X-ray phase analysis, scanning electron microscopy and X-ray microanalysis. This makes it possible to reveal structural, phase and chemical heterogeneity, determine the degree of amorphization of coatings, temperature and heat of crystallization of the amorphous phase during heating. The new integrated approach was used to study amorphous-crystalline coatings of the Ni-P, Fe-Ni-B and Fe-B systems produced by thermal spraying.

Microprobe X-ray studies of thermal spray coatings

2010 ◽  
Vol 1 (SRMS-7) ◽  
Author(s):  
P. D. Quinn ◽  
J. F. W. Mosselmans ◽  
D. G. McCartney ◽  
D. Zhang
Keyword(s):  
Thermal Spray ◽  
Protective Coatings ◽  
Thermal Spraying ◽  
Thermal Spray Coatings ◽  
Extreme Conditions ◽  
Structural Variations ◽  
Coating Performance ◽  
X Ray ◽  
Spray Coatings

Thermal spraying is emerging as the leading route for the deposition of protective coatings onto engineering components to improve operation under extreme conditions of temperature, wear or corrosion. Detailed microstructural assessment is a key element in improving coating performance, and this study demonstrates the application of microfocus X-ray techniques to the determination of elemental and structural variations in the coatings.

Image-Based Modeling for Assessing Thermal Conductivity of Thermal Spray Coatings at Ambient and High Temperature

2006 ◽  
Author(s):  
Y. Tan ◽  
A. Sharma ◽  
J. P. Longtin ◽  
S. Sampath ◽  
H. Wang
Keyword(s):  
Thermal Conductivity ◽  
High Temperature ◽  
Thermal Spray ◽  
Process Parameters ◽  
Thermal Spraying ◽  
Thermal Spray Coatings ◽  
Analysis Model ◽  
Element Analysis ◽  
Spray Coatings ◽  
Coating Microstructure

Thermal spray coatings are used extensively for protection of engineering components and structures in a variety of applications. Due to the nature of thermal spraying process, the coating thermal, mechanical, and electrical properties depend strongly on the coating microstructure, which consists of many individual splats, interfaces between the splats, defects and voids. The coating microstructure, in turn, is determined by the thermal spray process parameters. In order to relate coating process parameters to the final coating performance, then, it is desirable to relate coating microstructure to coating properties. In this work, thermal conductivity is used as the physical parameter of interest. Thermal conductivity of thermal spray coatings is studied by using an image analysis-based approach of typical coating cross sections. Three coating systems, yttria stabilized zirconia (YSZ), molybdenum, and Ni-5wt.%Al are explored in this work. For each material, thermal conductivity is simulated by using a microstructure image-based finite element analysis model. The model is then applied to high temperature conditions (up to 1200 °C) with a hot stage-equipped scanning electron microscope imaging technique to assess thermal conductivity at high temperatures. The coating thermal conductivity of metallic coatings is also experimentally measured by using a high-temperature laser flash technique.

scholarly journals A New Approach to Online Thickness Measurement of Thermal Spray Coatings

2006 ◽  
Vol 15 (4) ◽  
pp. 744-749 ◽  
Author(s):  
A. Nadeau ◽  
L. Pouliot ◽  
F. Nadeau ◽  
J. Blain ◽  
S.A. Berube ◽  
...  
Keyword(s):  
Thermal Spray ◽  
Thickness Measurement ◽  
Thermal Spray Coatings ◽  
New Approach ◽  
Spray Coatings

Methods of Determination and Control of Residual Stresses in Plasma Spray Coatings

1997 ◽  
Author(s):  
L. Dekhtyar ◽  
A. Kleyman ◽  
V. Andreychuk ◽  
S. Berman
Keyword(s):  
Residual Stresses ◽  
Thermal Spray ◽  
Plasma Spray ◽  
Thermal Spraying ◽  
Thermal Spray Coatings ◽  
Coating Deposition ◽  
Spray Coatings ◽  
Plasma Spray Coatings ◽  
And Control ◽  
Elastic Characteristics

Abstract Residual stresses exert profound influence on the longevity of parts with thermal spray coatings. The distribution and value of the residual stresses depend on method of coating deposition, composition of the applied material, parameters of thermal spraying and methods of post-treatment. Therefore, the study of the influence of the various technological factors on the residual stresses in the plasma spray coatings is very important. Due to heterogeneity of the coating, residual stresses can be determined only by the experimentation by using new methods which take into consideration real values of elastic characteristics and density of elementary layers. Methods and formulas for the calculations of the residual stresses in coatings deposited on bars, rings, discs, cylinders are presented. Experimental results for the various thermal spray coatings are also shown. These results can be used for the optimization of coating deposition and would supplement the existing database.

The Ultimate Spray Booth

1997 ◽  
Author(s):  
L. Pejryd ◽  
J. Wigren ◽  
N. Hanner
Keyword(s):  
Thermal Spray ◽  
Thermal Spraying ◽  
Thermal Spray Coatings ◽  
Design Element ◽  
Production Flow ◽  
Statistical Process ◽  
Spray Coatings ◽  
Spray Process ◽  
Spray Booth ◽  
On Line

Abstract Reproducibility is a current challenge for the thermal spray industry. Reproducibility associated problems represent a large cost every year not only in terms of rejections and rework, but also in costs for destructive testing and decreased production flow. Thermal spray coatings are moving in the direction of being considered only as a "band aid" to becoming a design element. One of the prerequisites for such a development is an increase in reproducibility for thermal spray coatings. The purpose of this paper is to outline a vision aiming in the direction of a future "ultimate spray booth", where thermal spraying is as reproducible and reliable as machining, grinding or other production processes. A way to increase reproducibility and reliability in the future spray shop involves utilising major parts of IT - technology. This also includes active co-operation design-production in the pre-spray process. This paper will deal with areas such as: operation drawings and lists through multimedia techniques, education programs for operators and designers through multimedia techniques, CAD/CAM, Off-line programming and simulation, On-line diagnostics of flame (particle diagnostics) and coating (temperature & Acoustic emission measurements), on-line Statistical Process Control and Knowledge Based System techniques.

Principles and Applications of Thermal Spray Coatings

2021 ◽  
pp. 31-70
Author(s):  
John Henao ◽  
Carlos A. Poblano-Salas ◽  
Fabio Vargas ◽  
Astrid L. Giraldo-Betancur ◽  
Jorge Corona-Castuera ◽  
...  
Keyword(s):  
Thermal Spray ◽  
Thermal Spraying ◽  
Industrial Applications ◽  
Thermal Spray Coatings ◽  
Flame Spray ◽  
Spray Coatings ◽  
Thermal Barriers ◽  
Energy Conversion Devices ◽  
Thermally Sprayed ◽  
Sprayed Coatings

The goal of the chapter is to address the fundamental theory of thermal spraying and its modern industrial applications, in particular, those involving flame spray, HVOF, plasma spray, and cold spray processes. During the last 30 years, thousands of manuscripts and various book chapters have been published in the field of thermal spray, displaying the evolution of thermally sprayed coatings in many industrial applications. Thermal spray coatings are currently interesting for different modern applications including prosthesis, thermal barriers, electrochemical catalysis, electrochemical energy conversion devices, biofouling, and self-repairing surfaces. The chapter will explain the fundamental principles of the aforementioned thermal spraying processes and discuss the effect of different controlling parameters on the final properties of the produced coatings. This chapter will also explore current and future industrial applications of thermal spray coatings.

USE OF IBA TECHNIQUES TO CHARACTERIZE HIGH VELOCITY THERMAL SPRAY COATINGS

2001 ◽  
Vol 15 (28n29) ◽  
pp. 1428-1436 ◽  
Author(s):  
W. TROMPETTER ◽  
A. MARKWITZ ◽  
M. HYLAND
Keyword(s):  
Thermal Spray ◽  
High Velocity ◽  
Sliding Wear ◽  
Thermal Spraying ◽  
Thermal Spray Coatings ◽  
Spray Coatings ◽  
The Past ◽  
Composition And Structure ◽  
Wide Range ◽  
Sprayed Coating

Spray coatings are being used in an increasingly wide range of industries to improve the abrasive, erosive and sliding wear of machine components. Over the past decade industries have moved to the application of supersonic high velocity thermal spray techniques. These coating techniques produce superior coating quality in comparison to other traditional techniques such as plasma spraying. To date the knowledge of the bonding processes and the structure of the particles within thermal spray coatings is very subjective. The aim of this research is to improve our understanding of these materials through the use of IBA techniques in conjunction with other materials analysis techniques. Samples were prepared by spraying a widely used commercial NiCr powder onto substrates using a HVAF (high velocity air fuel) thermal spraying technique. Detailed analysis of the composition and structure of the power particles revealed two distinct types of particles. The majority was NiCr particles with a significant minority of particles composing of SiO 2/ CrO 3. When the particles were investigated both as raw powder and in the sprayed coating, it was surprising to find that the composition of the coating meterial remained unchanged during the coating process despite the high velocity application.

scholarly journals An Investigation on Splat and Flattening Behavior of Thermally Sprayed Copper on A Rough Surface: A New Approach

2020 ◽  
Vol 2 (1) ◽  
pp. 37-42
Author(s):  
SATISH TAILOR ◽  
◽  
N Vashishtha ◽  
Ankur Modi ◽  
SC Modi ◽  
...  
Keyword(s):  
Rough Surface ◽  
Thermal Spraying ◽  
Thermal Spray Coatings ◽  
Polished Surface ◽  
Spray Parameters ◽  
Splat Formation ◽  
New Approach ◽  
Spray Coatings ◽  
Optimization Study ◽  
Thermally Sprayed

All thermal spray coatings are finally deposited on a rough and active grit-blasted surface of the job. But, available literatures are reporting splat and flattening behavior on a polished surface. There is a gap in thermal spraying to understand actual solidification on a rough surface. Therefore, in the present work an attempt has been made to study of splat formation of thermally sprayed copper onto grit-blasted rough surface. An optimization study is done to collect rounded/semi-rounded disk like splats to set spray parameters. Optimized parameters were also tested at four different gun traverse speeds to fabricate thin Cu coatings (30-50µm).

Thermal Spraying of Wear and Corrosion Resistant Surfaces

2008 ◽  
Vol 384 ◽  
pp. 75-98 ◽  
Author(s):  
Bernhard Wielage ◽  
Thomas Lampke ◽  
Thomas Grund
Keyword(s):  
Thermal Spray ◽  
Thermal Spraying ◽  
Base Material ◽  
Thermal Spray Coatings ◽  
Selective Coating ◽  
Spray Coatings ◽  
Wear And Corrosion ◽  
Parameter Field ◽  
Thermal Spray Processes ◽  
Sprayed Coatings

Thermal spraying is one of the most variable and diverse surface coating techniques concerning materials to be processed as well as possible geometries to be coated. The group of thermal spray processes covers a large parameter field to combine nearly each coating with each base material. Thermally sprayed coatings can be applied very evenly and therefore allow to be applied on final-shaped components. Otherwise, if further treatment or finishing is necessary, thermal spray coatings can be processed by grinding or even milling. Masking during the coating process permits the selective coating of specific surface parts or the application of required geometrically structures, e. q. conductor structures. The main application field of thermal spray coatings is the (combined) wear and corrosion protection of selected component parts.

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