ISO 24688:2022

INTERNATIONAL ISO
STANDARD 24688
First edition
2022-07
Determination of modulation period
of nano-multilayer coatings by low-
angle X-ray methods
Reference number
ISO 24688:2022(E)
© ISO 2022

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ISO 24688:2022(E)
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© ISO 2022
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Published in Switzerland
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ISO 24688:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Substrate conditions .1
5 Testing of modulation period . 1
5.1 Principle for low-angle X-ray methods . 1
5.1.1 General . 1
5.1.2 XRR method . 1
5.1.3 GIXRD method . 2
5.1.4 Calculating formula. 3
5.2 Specifications concerning the coated sample . 4
5.2.1 Size specifications for the coated sample. 4
5.2.2 Periods specifications for the coated sample . 4
5.2.3 Surface roughness requirements of the coated sample . 4
5.3 Specifications for X-ray measuring apparatus . 5
5.3.1 Apparatus configuration . 5
5.3.2 Beam conversion device . 5
5.3.3 Radiation sources and filters . 5
5.4 Calibrating of apparatus . 5
5.5 Testing conditions . 6
5.6 Test and calculation procedure . 6
Annex A (informative) Process of determination of modulation period by XRR .7
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ISO 24688:2022(E)
Foreword
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This document was prepared by Technical Committee ISO/TC 107, Metallic and other inorganic coatings,
Subcommittee SC 9, Physical vapor deposition coatings.
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ISO 24688:2022(E)
Introduction
Nano-multilayer coatings by physical vapor deposition (PVD), which possess high coating-substrate
adhesion, high hardness and good wear resistance, corrosion resistance and conductive resistance,
have been widely applied on tools, moulds, microelectronics and other important parts to improve their
service life. Nano-multilayers formed by depositing two materials alternately at nanometer scale have
attracted considerable interest due to their superior physical and chemical properties. The modulation
period refers to the thickness of these two alternate layers.
Based on the chemical compositions, the main nano-multilayer coatings involve metal/metal, metal/
ceramic and ceramic/ceramic systems such as Cu/Ni, Cu/W, Cu/Ag, Ti/TiN, Cr/CrN, Zr/ZrN, TiN/CrN,
CrN/AlCrN, TiC/TiCN and CrAlN/AlCrTiSiN. The key factor influencing the properties of nano-multilayer
coatings was previously the modulation period, which has an important effect on properties including
hardness, toughness, electromagnetic and optical property. For example, as the modulation period
decreases, the hardness of the nano-multilayer coatings increases. At present, the high-resolution
projection electron microscope (HR-TEM) and the X-ray methods including the X-ray reflectivity (XRR)
and glancing incident X-ray diffraction (GIXRD) are the two common methods for determining the
modulation period of the nano-multilayer coatings. X-ray methods are more suitable for determination
of the modulation period due to the advantages of being non-destructive, statistical, convenient and
accurate compared with HR-TEM.
However, there is not yet any standard to qualify the modulation period of these nano-multilayer
coatings, which limits their further development.
Thus, the motivation of this document is to prescribe the calculation of the modulation period of the
nano-multilayer hard coatings and the measurement conditions of X-ray methods. The modulation
period is an important technical indicator of the nano-multilayer coatings, which can also provide the
communication bridge for customers who want to use the coatings, tool coater and analytic service
provider. This document can be used for quality assurance of products with nano-multilayer coatings.
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INTERNATIONAL STANDARD ISO 24688:2022(E)
Determination of modulation period of nano-multilayer
coatings by low-angle X-ray methods
1 Scope
This document specifies the substrate conditions and testing of the modulation period (including
the principles for low-angle X-ray methods, the requirements of the coatings, the requirements for
X-ray measuring apparatus, the calibration of apparatus and samples, and the testing conditions and
calculation process) of nano-multilayer coatings by low-angle X-ray methods including X-ray reflectivity
(XRR) and glancing incident X-ray dif
...