Smart Magnet Application as an Anti-radar Material

Smart Magnet Application as an Antiradar Material

By

I Gusti Agung Putra Adnyana, S.Si., M.Si.

Department  of  Physics,  Faculty  of  Mathematics  and  Natural  Sciences,  Udayana University

igaadnyana@unud.ac.id

adio Detection and Ranging better known as Radar is a detection system that utilizes electromagnetic waves to determine the presence, type, distance, movement and speed of an object. Perhaps many people do not know that the term radar itself was first used in 1941, the term radar is used to replace the term Radio Direction Finding (RDF). But actually detecting the existence of an object using electromagnetic waves was applied in 1904.That is, the use of electromagnetic wave reflection to detect the presence of an object has been done long before the term known Radar.

Physicists who played an important role in the existence of Radar, namely James Clerk Maxwell with electromagnetic theory, Heinrich Rudolf Hertz who succeeded in proving the existence of electromagnetic waves, Christian Hülsmeyer scientists who succeeded in using electromagnetic waves to detect the presence of objects, and Robert Watson-Watt scientists from Scotland, who began developing research on the embryo of radar in 1915.

Basically, the working principle of Radar is to measure the distance of the wave travel from the sensor to the target. By emitting electromagnetic waves and recapturing the reflected waves, the distance travelled from the sensor on the radar to the target can be calculated. The trick is to measure the time it takes for electromagnetic waves to propagate from the sensor to the target and back to the sensor.

In its development, radar is utilized in various joints of human life, such as: weather radar, radar for shipping and aviation, radar mitigation and early warning, and so forth.

In the field of defense and security, radar has a very important and very strategic role as one of the technologies that can assist in the security of a country's territory. The first Indonesian-made radar produced was named INDRA. There are two Radar products made by the children of the nation, namely the Beach Supervisor Radar and the Ship Navigation Radar.

In line with the existence and development of radar, the development of Antiradar is also advancing rapidly. Until now this technology continues to be developed to achieve optimal results. The principle of antiradar work is to capture electromagnetic waves as much as possible so that almost nothing is reflected back to the radar. In other words; the existence, type, distance, movement and speed of an object are not detected or disguised. Based on these working principles, antiradar technology is developed, both done by form engineering (shape) and material engineering (Radar Absorbant Material).

Radar Absorbing Material (RAM) is a material used as material that can absorb and weaken reflected electromagnetic waves. One material that is used as RAM is a magnetic material. Engineering materials made from magnets is material engineering and material composition to produce a composition of smart magnets with the desired characteristics.

Smart Magnets are magnetic materials that are made with their characteristics tailored to their uses and uses. Smart Magnet application has entered into all lines of human life such as the use of magnets in the health or medical fields, one of which is MRI (Magnetic Resonance Imaging) which makes it easy for doctors to diagnose diseases in the body. Another very strategic use is in the field of defense and security, namely, smart magnets as anti-radar materials.

How can smart magnets be used as anti-radar materials? An interesting question to know the answer to. Antiradar smart magnets, made and developed from magnetic materials based on Barium Hexa-ferrite based materials. Barium Hexa-ferrite has material parameters whose characteristics can affect the amount of electromagnetic wave absorption. With the advantages possessed, it is possible to obtain smart magnets that have the potential to be good absorbents of electromagnetic waves.

In its application, the basic ingredients of Barium Hexa-ferrite are further modified by the addition of other ingredients (doping) to find the right material composition (mixture of ingredients) and as expected. Magnetic materials whose modified magnetic structure must have a maximum absorption capacity.

The result material which is as an absorber and in the form of smart magnet powder will then be combined with a paint material with a certain ratio so that the resulting paint or coating for antiradar.

The application for developing an anti-radar paint prototype as a result of the innovation of the nation's children has been successfully tested on one of the Indonesian Navy's defense equipment, namely the Patkamla SADARIN ship. So, this Smart Magnet material is a very strategic product especially for the National Defense Sector. Barium Hexa-ferrite-based Smart Magnet material is dominated by raw materials with a very large iron oxide content. While iron oxide is found in many iron sand minerals. Bali has abundant iron sand mineral deposits stretching along the coast. This is an opportunity for Indonesia as one of the countries that have abundant iron sand resource potential and if the reserves are known, it can be developed into a commercial industrial scale.

Research on Barium Hexa-ferrite based magnets will continue to grow along with the use of smart magnets which is increasingly widespread in the 4.0 era which is thirsty for technological innovation, as has been done in the FMIPA Physics Study Program at Udayana University, especially in the field of Material Physics competence.  In addition to developing superconductors, some of his research has led to magnetic materials. Research on permanent magnets begins with research on the mineral content of iron in sand found in several sand beaches in Bali. This study aims to see how much potential the metal content of iron minerals in Bali.

At present, research on permanent magnets in the Physics Study Program is at the stage of using rare earth as doping. This aims to improve the characteristics and quality of the magnet, which ultimately hopes to produce a product with quality that can continuously be improved.