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Nowadays there is an increasing interest in innovative techniques used to inspect the internal part of materials to check if some flaws are present inside it, to have a quantitative measure of its mechanical properties. The main goal of these innovative techniques is to test the material without destroying it and for this reason these techniques are called non-destructive inspection techniques (NDT). Thermography is an NDT technique that allows detecting flaws inside a material by mean of observing it with a thermal camera. It is largely diffusing among industries and it's becoming a must in the quality checks and inspection phase. There are applications also in the medical field, for illness (like diabetes and vascular disorder) and tumour detection. In this article I will describe the working principle of thermography, providing some examples of real applications. How thermography works Thermography is based on the observation of a body using a thermal camera , exploiting ...

A thermal camera is an electronic device that allows transforming the infrared radiation emitted by any kind of body in a coloured image. Indeed, any body whose temperature is greater than 0 K (the absolute zero) emits radiation in the infrared spectrum. This is what we call heat . The infrared radiation is not visible to the human eye, so we need a particular device to visualize it. And here the thermal camera comes. But how does a thermal camera works? And how does it allow us to transform this infrared radiation, that is not visible, into a coloured image that we can see on a screen? Let see it more in detail. How a thermal camera works The scheme describing how a thermal camera works is the following: A sensitive element transforms the infrared radiation, namely, the heat emitted by a body into an electrical charge. This is possible also if the observed body is at a certain distance and really near to the thermal camera; This electrical charge is collected on an electron...

The importance of materials for Space applications Space is a really harsh environment, not only for astronauts but also for materials. Radiations, atomic oxygen, outgassing, debris and micrometeorites, high and low temperatures are the main problems materials for Space applications have to deal with. For this reason, a structure that wants to stay in Space has to be made with some specific materials, such that it can guarantee mechanical and functional properties and protect astronauts. Let's describe all these problems more in detail and see which are the main adopted solutions. Radiation Radiations represent the most famous problem in Space related to astronauts health. In fact, materials for Space applications have to be able to protect astronauts but also to maintain their mechanical and functional properties. Radiations are divided into two main categories: UV radiations and ionizing radiations .  UV radiation UV radiation has a really detrimental effect on polymeric...

What is Metal Additive Manufacturing Additive Manufacturing is a technology that allows creating objects adding material layer by layer. In Metal Additive Manufacturing the material involved is metal. There are different types of Metal Additive Manufacturing. Here the most important are reported. Directed Energy Deposition (DED) Metal Additive Manufacturing   Directed Energy Deposition is composed of a head from where a laser, or an electron or a plasma ray exits. On the head, a pressurized system is installed, from where metal powder is ejected in a way that hits the ray and melting occurs. Both the head and component can move. It is possible to use, instead of powder, a filament, cheaper but that gives lower quality. Powder Bed Fusion Metal Additive Manufacturing In Powder Bed Fusion , a bed of powder is deposited and material is melted only where necessary. Once the material is melted, another layer of powder is deposited, and so on. Depend...