Change in the resistance of metals with the introduction of impurities. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Power Supplies
Comments on the article
The introduction of impurities into metals always increases their resistivity. But it is curious that some impurities practically do not affect the resistivity, while others, even in small quantities, change it dramatically.
Figure 1 shows how the resistivity of iron changes when impurities of various elements are introduced into it. Silicon (Si) has the most dramatic effect. That is why electrical steels contain a high percentage of silicon. It is necessary to increase the resistivity of steel in order to reduce eddy current losses in the cores of transformers.
In Fig. 2, the same diagram is given for aluminum.
Here, manganese (Mn) most strongly affects the resistivity, for silver (Fig. 3) such an impurity is antimony (Sb).
Finally, let's turn to copper (Fig. 4).
Phosphorus (P), silicon (Si) and iron (Fe) most affect the resistivity of copper. But let's pay attention to the modest contribution of nickel (Ni). Let's expand the chart to 100% (Fig. 5).
From left to right in the diagram, the nickel content increases and the copper content decreases. It can be seen from the diagram that the highest resistivity of the nickel-copper alloy is observed at a ratio of 58% copper and 42% nickel. This alloy has unique properties: when the temperature changes over a wide range, its resistivity practically does not change. For this, the alloy was named constantan (from the Latin constantis - constant). This alloy wire is used for high stability precision resistors and other applications where high stability is required.
See other articles Section Power Supplies.
Read and write useful comments on this article.
<< Back
Latest news of science and technology, new electronics:
Traffic noise delays the growth of chicks
06.05.2024
The sounds that surround us in modern cities are becoming increasingly piercing. However, few people think about how this noise affects the animal world, especially such delicate creatures as chicks that have not yet hatched from their eggs. Recent research is shedding light on this issue, indicating serious consequences for their development and survival. Scientists have found that exposure of zebra diamondback chicks to traffic noise can cause serious disruption to their development. Experiments have shown that noise pollution can significantly delay their hatching, and those chicks that do emerge face a number of health-promoting problems. The researchers also found that the negative effects of noise pollution extend into the adult birds. Reduced chances of reproduction and decreased fertility indicate the long-term effects that traffic noise has on wildlife. The study results highlight the need ... >>
Wireless speaker Samsung Music Frame HW-LS60D
06.05.2024
In the world of modern audio technology, manufacturers strive not only for impeccable sound quality, but also for combining functionality with aesthetics. One of the latest innovative steps in this direction is the new Samsung Music Frame HW-LS60D wireless speaker system, presented at the 2024 World of Samsung event. The Samsung HW-LS60D is more than just a speaker system, it's the art of frame-style sound. The combination of a 6-speaker system with Dolby Atmos support and a stylish photo frame design makes this product the perfect addition to any interior. The new Samsung Music Frame features advanced technologies including Adaptive Audio that delivers clear dialogue at any volume level, and automatic room optimization for rich audio reproduction. With support for Spotify, Tidal Hi-Fi and Bluetooth 5.2 connections, as well as smart assistant integration, this speaker is ready to satisfy your ... >>
A New Way to Control and Manipulate Optical Signals
05.05.2024
The modern world of science and technology is developing rapidly, and every day new methods and technologies appear that open up new prospects for us in various fields. One such innovation is the development by German scientists of a new way to control optical signals, which could lead to significant progress in the field of photonics. Recent research has allowed German scientists to create a tunable waveplate inside a fused silica waveguide. This method, based on the use of a liquid crystal layer, allows one to effectively change the polarization of light passing through a waveguide. This technological breakthrough opens up new prospects for the development of compact and efficient photonic devices capable of processing large volumes of data. The electro-optical control of polarization provided by the new method could provide the basis for a new class of integrated photonic devices. This opens up great opportunities for ... >>
| Random news from the Archive Remote Parent Meeting
25.01.2014
"I was not at the meeting due to problems with the Internet." It is quite possible that some parents who did not get to the parent meeting will soon name just such a reason. This spring, the Department of Education and the Department of Information Technology will begin the 2nd phase of the School of New Technologies project.
The head of the Department of Information Technologies (DIT) Artem Ermolaev spoke about new technologies used in the field of primary education during the awards ceremony for the schools that became winners of the first stage.
The city authorities are going to select this year 200 schools that have shown the best results in the competitive selection process, and, in addition, will present the most interesting applications.
The head of the Department of Information Technologies recalled that the status of "school of new technologies" will give the educational institution certain advantages, and first of all, technological and financial support from the city.
For example, this year 20 Moscow schools that won the first stage will receive an Internet channel providing a connection speed of 100 Mbps, technical support for the development of distance learning, as well as additional computing power, including access to the city's web conferencing system. for the purpose of holding parent-teacher meetings online. The finished terms of reference will appear by April 1, after which 20 schools will begin to connect to the city's IT infrastructure. Also, a new course "Useful Internet" will appear in these schools, and internships will be held from the partner companies of the project.
Artem Ermolaev recalled what kind of applications the authorities expect from future project participants. "It is very important that this is a real project, and we can see what effect you want to achieve," said the head of DIT.
The School of New Technologies project was launched last year. Its main focus is to encourage schools to more actively use modern technologies in the educational process. The project is carried out in the form of competitive selection, which consists of several stages. During these stages, the level of development of educational institutions in terms of technology is assessed. Professional participants in the telecommunications and information technology market participate in the selection of winners. The first stage was completed last year. 20 schools became its winners.
|
Other interesting news:
▪ X-ray for communication in space
▪ The car will not hit a pedestrian
▪ Slippers with car parking
▪ The first Soviet meteorological satellite deorbited 43 years after launch
▪ Children lengthen your life
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ section of the site for the Musician. Selection of articles
▪ article Two-story breadbasket. Tips for the home master
▪ article Why the brick from which the walls of the Kremlin are built, Aristotle? Detailed answer
▪ Tulip article. Legends, cultivation, methods of application
▪ article Fluorescent lamps. Directory
▪ article Protection device for a three-phase motor against phase failure. Encyclopedia of radio electronics and electrical engineering
Leave your comment on this article:
All languages of this page
Home page | Library | Articles | Website map | Site Reviews
www.diagram.com.ua
2000-2024
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese