TY - JOUR
T1 - Continuous in‐line chromium coating thickness measurement methodologies
T2 - An investigation of current and potential technology
AU - Jones, Adam
AU - Uggalla, Leshan
AU - Li, Kang
AU - Fan, Yuanlong
AU - Willow, Ashley
AU - Mills, Christopher A.
AU - Copner, Nigel
N1 - Funding Information:
Funding: Knowledge Economy Skills Scholarships (KESS) is a pan‐Wales higher‐level skills initia‐ tive led by Bangor University on behalf of the HE sectors in Wales. It is part funded by the Welsh Government’s European Social Fund (ESF) program for East Wales.
Funding Information:
Knowledge Economy Skills Scholarships (KESS) is a pan?Wales higher?level skills initiative led by Bangor University on behalf of the HE sectors in Wales. It is part funded by the Welsh Government?s European Social Fund (ESF) program for East Wales.
Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/5/11
Y1 - 2021/5/11
N2 - Coatings or films are applied to a substrate for several applications, such as waterproofing, corrosion resistance, adhesion performance, cosmetic effects, and optical coatings. When applying a coating to a substrate, it is vital to monitor the coating thickness during the coating process to achieve a product to the desired specification via real time production control. There are several different coating thickness measurement methods that can be used, either in‐line or off‐line, which can determine the coating thickness relative to the material of the coating and the substrate. In‐line coating thickness measurement methods are often very difficult to design and implement due to the nature of the harsh environmental conditions of typical production processes and the speed at which the process is run. This paper addresses the current and novel coating thickness methodologies for application to chromium coatings on a ferro‐magnetic steel substrate with their advantages and limitations regarding in‐line measurement. The most common in‐line coating thickness measurement method utilized within the steel packaging industry is the X‐ray Fluorescence (XRF) method, but these systems can become costly when implemented for a wide packaging product and pose health and safety concerns due to its ionizing radiation. As technology advances, nanometer-scale coatings are becoming more common, and here three methods are highlighted, which have been used extensively in other industries (with several variants in their design) which can poten-tially measure coatings of nanometer thickness in a production line, precisely, safely, and do so in a non‐contact and non‐destructive manner. These methods are optical reflectometry, ellipsometry and interferometry.
AB - Coatings or films are applied to a substrate for several applications, such as waterproofing, corrosion resistance, adhesion performance, cosmetic effects, and optical coatings. When applying a coating to a substrate, it is vital to monitor the coating thickness during the coating process to achieve a product to the desired specification via real time production control. There are several different coating thickness measurement methods that can be used, either in‐line or off‐line, which can determine the coating thickness relative to the material of the coating and the substrate. In‐line coating thickness measurement methods are often very difficult to design and implement due to the nature of the harsh environmental conditions of typical production processes and the speed at which the process is run. This paper addresses the current and novel coating thickness methodologies for application to chromium coatings on a ferro‐magnetic steel substrate with their advantages and limitations regarding in‐line measurement. The most common in‐line coating thickness measurement method utilized within the steel packaging industry is the X‐ray Fluorescence (XRF) method, but these systems can become costly when implemented for a wide packaging product and pose health and safety concerns due to its ionizing radiation. As technology advances, nanometer-scale coatings are becoming more common, and here three methods are highlighted, which have been used extensively in other industries (with several variants in their design) which can poten-tially measure coatings of nanometer thickness in a production line, precisely, safely, and do so in a non‐contact and non‐destructive manner. These methods are optical reflectometry, ellipsometry and interferometry.
KW - Chromium
KW - Coating thickness measurement
KW - Optical metrology
KW - Steel substrate
UR - http://www.scopus.com/inward/record.url?scp=85105702770&partnerID=8YFLogxK
U2 - 10.3390/s21103340
DO - 10.3390/s21103340
M3 - Review Article
C2 - 34064984
AN - SCOPUS:85105702770
SN - 1424-8220
VL - 21
JO - Sensors
JF - Sensors
IS - 10
M1 - 3340
ER -