Electron beam fusion (EBM) is a rapid manufacturing method that uses an electron beam in a vacuum to fuse layers of powder to create complex parts with high density and desirable physical characteristics. EBM is suitable for use with metals, ceramics, and metal-ceramic composites and is often used to produce high-performance parts such as turbine […]
Electron beam machining uses concentrated heat to melt metal in a vacuum, producing smoother surfaces and precise results. It is mainly used in the electronics industry due to equipment costs and limitations. It can cut various metals and alloys and is used for welding and annealing. Non-vacuum EBM reduces power and thickness of metals machined. […]
Electron capture occurs when a proton in an atom’s nucleus attracts an orbiting electron, causing the atom to decay and become a different element with the same atomic mass. This process requires less energy than other types of radioactivity and usually involves electrons from the K or L electron shells. The captured electron is absorbed […]
Electron configuration is the arrangement of electrons around an atom’s nucleus in its ground state. Shells are designated by integers and contain orbitals, which are designated s, p, d, and f. Each shell can hold a maximum of 2n2 electrons. Lower energy shells and orbitals are filled before higher ones. Electron configuration is important in […]
Electrons are negatively charged subatomic particles that, along with protons and neutrons, make up atoms. They are involved in chemical bonding, electricity, and the solidity of objects. Electrons can behave like waves and are arranged in shells around atoms. Chemical elements’ properties depend on the number and arrangement of electrons. Atoms combine to form molecules […]
Electron beam welding uses high-energy electrons to melt metal and create a weld without a filler wire. It requires a vacuum and is expensive, but produces high-quality, deep welds with minimal distortion. It can join dissimilar and reactive metals, but is limited by equipment cost and size constraints. Electron beam welding (EBW) is a fusion […]
Transmission electron microscopy (TEM) uses beams of electrons to image very thinly sectioned samples at high resolutions. TEMs have played important roles in virology, cancer research, materials study, and microelectronics R&D. The first TEM prototype was built in 1931, and the technology was refined over the following decades. Scanning transmission electron microscopy (STEM) was developed […]
Electron capture detectors emit beta particles and gases to detect chemical compounds in samples. They generate a current by scattering electrons and detecting changes in electrical current. Modern detectors use plasma and operate in DC or pulsed mode. They are used in gas chromatography and require careful handling and regulatory compliance. Only authorized professionals may […]
Auger electron spectroscopy (AES) identifies the chemical composition of a surface layer using electrons or X-rays. The energy of emitted particles is unique to the element, and peaks on a graph identify compounds. The technique is used in physical and chemical applications, but can damage the surface. Auger electron spectroscopy (AES) is often used to […]
Electron volts (eV) are a small unit of energy used in physics research, derived from the energy required to move a single electron through an electrical potential of one volt. They are used in fields such as nuclear and particle physics, astronomy, and chemistry. While not a standard metric unit, they can be used to […]
The scanning electron microscope uses high-energy electron beams to create accurate, three-dimensional images of small specimens, such as viruses. Proper sample preparation is crucial, and images are always in black and white. The scanning electron microscope is a piece of equipment that uses high-energy electron beams to generate information about a microscopy sample. The generated […]
Electron beams can be used for welding, manufacturing precision parts, sterilizing medical supplies and food, and eliminating microbial organisms. Advantages include a narrow weld zone and the absence of a filler material, but there are downsides such as x-ray production and high costs. Electron Beam Freeform Fabrication (EBF3) can fabricate parts from raw materials, saving […]
Electron affinity is the energy released when an atom absorbs an electron. Attracting an electron requires energy, and elements in groups 6 and 7 are more likely to attract electrons. Heavier atoms have lower electron affinity, and oxygen and sulfur can attract two more electrons. Atoms have protons, neutrons, and electrons, with the number of […]
Electron microscopes use electrons instead of photons for imaging, providing much greater magnification due to their smaller wavelength. There are four types, with the transmission and scanning electron microscopes being the most common. They offer high resolution and can observe individual atoms on a surface, but are expensive to purchase and maintain. Samples must be […]
An electron gun inside a CRT produces a beam of electrons that illuminates a phosphor coating on the inside surface of a TV or computer monitor. The beam must hit each pixel about 70 times per second to produce a particular color on the screen. Modern flat screens do not use an electron gun. An […]
Electron spin resonance (ESR) is a spectroscopy used on paramagnetic materials with unpaired electrons. ESR has applications in chemistry, biology, and quantum computing. ESR detects free radicals and can be used to date teeth. ESR is also used in artificial photosynthesis and quantum computing. Electron spin resonance (ESR) is a form of spectroscopy used on […]
Electric current is the flow of electrons, powered by the electromagnetic force. Alternating current (AC) and direct current (DC) are the two main types of electron flow used to power electronic devices. Amps are the standard unit of measure for electron flow. A stream of electrons is an electric current, the same thing that powers […]
