Welcome to the Surface Roughness Analysis Blog
Why do brakes squeak? When will a gasket leak? What caused the haziness in my painted finish?
Surface texture and function are tightly linked. Understanding the relationship between texture and function, and sharing that information with engineers and quality professionals, is what Michigan Metrology is all about.
The articles in this blog explore the concepts of surface texture analysis and measurement. We show how you can apply these concepts to solve problems related to leaks, squeaks, appearance, wear, noise, fit, friction, vibration, adhesion, and many other functions.
Looking for more information on specific surface texture parameters? Visit our Surface Texture Parameters Glossary for an introduction to dozens of 3D surface roughness analysis parameters.
And, if you want to learn much more about surface texture consider attending our online and in-person classes for an immersive introduction to the many concepts in surface analysis.
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Analyzing steel clutch reaction plates
July 15, 2020Applying the Material Ratio parameters — case study In our post of a few weeks ago we discussed the Stylus (X,Y) parameters, which are derived from the 2D Bearing Ratio
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Surface texture measurement – Ra, Rz, Rmax, Rz1max, Maximum Height
June 22, 2020This article discusses several key surface texture measurement parameters: average roughness (Ra), average maximum surface height (Rz), maximum of all per-sampling-length peak-to-valley heights (RMax), and the Maximum Height (Rz1max). We
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Surface finish for medical devices
June 14, 2020Artificial medical devices prolong life and preserve quality of living. To design devices that will function reliably and safely for decades requires careful attention to materials and surface finish. Accurately
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Parameters Primer: Stylus(X,Y) Parameters
May 12, 2020The Stylus (X, Y) parameters (Rk, Rpk and Rvk) are derived from the Bearing Area Curve, based on the ISO 13565-2:1996 standard. The Bearing Area Curve, (also called the Bearing Ratio Curve, or
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Nanometer-scale roughness
April 11, 2020“Nanometer-scale” surface roughness may seem rare and specialized. But, in fact, many components and common products require nanometer-scale, or sub-nanometer-scale, average roughness (Sa) in order to function properly. The ability to
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How many measurements?
March 3, 2020Multiple surface texture measurements made in different locations over a surface will generally demonstrate some variation in the texture parameter being assessed, such as average roughness (Ra) or peak-to-valley height
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What wear measurement may and may not show you
March 10, 2019One of the great challenges of product design is accurately assessing how a component will wear in order to maximize its useful lifetime. Wear is, of course, caused by a
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Parameter Primer: Sds (Summit Density)
February 9, 2019Sds, the Summit Density, is one of the so-called “Hybrid” surface texture parameters. Sds counts the number of summits per unit area of the surface. The summits are derived from
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Surface texture measurement – did you set the cutoff lengths properly?
January 21, 2019Along with specifying the surface roughness with Ra (average roughness), one must establish the cutoff lengths used to measure the surface. A specification of Ra alone is inadequate, since measurement
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Take a hike! Understanding form, waviness and roughness in terms of a good walk
January 8, 2019The terms “roughness,” “waviness” and “form” are used everywhere in discussions of surface texture. But do we really understand how they are defined? For many years I have used an
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If you need less sliding friction, should you make the surface rougher or smoother?
July 6, 2018How is sliding friction affected by the surface texture of two dry parallel sliding surfaces? The relationship of dry (sliding) friction to surface texture is linked to the notion of
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Patent attorneys and surface texture
March 3, 2018When an invention is in an esoteric field, such as tribology or surface metrology, it is especially important for the inventor to assist the patent attorney in understanding the novel