Thermal and mechanical treatments are available to relieve residual stresses.

Thermal treatments

The thermal treatments are generally a more common way to relieve residual stresses than mechanical treatments. The thermal treatments usually do not induce any new residual stresses to balance existing residual stresses’ negative effects. Thermal treatments can be separated into two categories as preheating and post-heating treatments.

Preheating

Preheating is heating the component to increase its temperature to a higher degree than the room temperature and, to a close degree, to the process temperature. The degree of the temperature depends on the material and the process. …


Distortion is the unexpected, uneven change in size or shape caused by dissimilarities in manufacturing and heat treatment processes. Distortion is affected by material properties, part geometry, the component’s size, and, most importantly, the component’s residual stress state.

Residual stresses can be strong enough to exceed the yield strength of the material. Once the yield strength is exceeded, plastic deformation as a shape change will occur. Heat treatment is one of the most common methods which is applied to relieve the residual stresses. …


Line Confocal Imaging (LCI) is an optical technology for high-speed 2D and 3D topography and tomography measurements.

Working principle

Line Confocal Imaging is based on the lateral chromatic aberration principle in which different wavelengths are focused at different heights.

The LCI uses a powerful white LED containing all visible wavelengths as the light source. The generated light goes through the illumination optics and is collected by the imaging optics.

The illumination optics separate the light into different wavelengths and project horizontal lines of each wavelength at different heights onto the target’s surface.

Simultaneously, the imaging optics collect wavelength and intensity…


There are many methods to measure residual stresses. The methods are commonly grouped as non-destructive, semi-destructive, and destructive. Or diffraction-based, strain relaxation-based, and other methods. However, they all have the same common point, being indirect. Yes, there is no direct method to measure stresses; they are calculated or derived from a measured quantity such as elastic strain or displacement. Let’s briefly look at the most common methods now.

Diffraction based methods

In diffraction-based methods, the elastic strain is measured using Bragg’s law. The stress calculation is done with Hooke’s law and elastic modulus (E) and Poisson’s ratio (ν).

Bragg´s law is expressed as


Residual stress measurement is one essential way to determine if the component can withstand the demanding load and stress conditions in its service life. The possibility of distortion of the component during storage or in-service life can also be checked by measuring the residual stresses. In fact, measurement is the only way to find the sign and magnitude of residual stresses. Measurement of residual stresses is also useful for quality control purposes and verification of processes such as surface hardening, heat treatment, machining…

For some dynamically loaded critical components such as crankshafts, residual stress measurements are often made for various…


The definition of a touch gesture

A touch gesture is used for interacting with a touch-enabled device to enhance the experience with it.

The function of a touch gesture

The touch gesture allows a user to control features of touch-enabled devices such as opening an application, navigating between menus, locking, unlocking the device, taking a screenshot, running a specific task, etc.

Advantages of a touch gesture

A touch gesture is easier to learn than a traditional control mechanism. Hence, it saves time by cutting the learning curve of a new user interface and its control functions. A touch gesture also saves space on a touch user interface by completing a process without any physical button. The benefits…


Barkhausen noise is a noise-like signal, generated when a magnetic field is applied to a ferromagnet.

History of Barkhausen noise

The nature of Barkhausen noise was explained already in 1919 by Prof. Heinrich Barkhausen.

However, Barkhausen noise started to be used in industrial applications as an analysis method at the beginning of the 1980s. Today, it is a recognized nondestructive method for materials characterization and heat treatment defect testing.

How is Barkhausen noise generated?

To generate Barkhausen noise, the material must be magnetized; hence it is applicable only for ferromagnetic materials, which are steel (except Austenitic), Nickle and Cobalt, and their alloys.

Ferromagnetic materials are composed of magnetic domains


A shorter description would be; people relate themselves with statements that could apply to many people.

History

The Barnum Effect is named after Phineas Taylor Barnum, who was a circus showman. During his performances, he was using such vague statements to catch the attention of the audience, and he made them believe him as he knew specifics of their lives. He was known as a person who knew something about everybody.

The naming of the psychological phenomenon may have been attributed to Barnum by Paul Meehl, an American psychologist.

Barnum Effect is also known as the Forer Effect because Bertram…

Murat Deveci

I studied engineering and industrial management, and I have been working in technical sales and marketing positions. My personal website is murat.fi

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