Periodic Tables Material Tables Chemical Elements Common Materials Materials Science What is material? A material is defined as a substance (most often a solid, but other condensed phases can be included) that is intended to be used for certain applications. There are a myriad of materials around us – they can be found in anything from buildings to spacecraft. On the basis of chemistry and atomic structure, materials are classified into three general categories: Metals (metallic elements), Ceramics (compounds between metallic and nonmetallic elements), Polymers (compounds composed of carbon, hydrogen, and other nonmetallic elements). Metals (metallic elements), Ceramics (compounds between metallic and nonmetallic elements), Polymers (compounds composed of carbon, hydrogen, and other nonmetallic elements). Real materials are never perfect . Classification of crystallographic defects ( microscopic defects ) is frequently made according to the geometry or dimensionality of the defect. Key mechanical design properties are: Stiffness . Stiffness is the ability of an object to resist deformation in response to an applied force. Strength . Strength is the ability of a material to resist deformation. Hardness . Hardness is the ability to withstand surface indentation and scratching. Ductility . Ductility is the ability of a material to deform under tensile load (% elongation). Toughness . Toughness is the ability of a material to absorb energy (or withstand shock) and plastically deform without fracturing. Stiffness . Stiffness is the ability of an object to resist deformation in response to an applied force. Strength . Strength is the ability of a material to resist deformation. Hardness . Hardness is the ability to withstand surface indentation and scratching. Ductility . Ductility is the ability of a material to deform under tensile load (% elongation). Toughness . Toughness is the ability of a material to absorb energy (or withstand shock) and plastically deform without fracturing. Metal is a material (usually solid) comprising one or more metallic elements (e.g., iron, aluminium, copper, chromium, titanium, gol d , nickel). Steels are iron–carbon alloys that may contain appreciable concentrations of other alloying elements. Adding a small amount of non-metallic carbon to iron trades its great ductility for the greater strength . An alloy is a mixture of two or more materials, at least one of which is a metal. Alloys can have a microstructure consisting of solid solutions, where secondary atoms are introduced as substitutionals or interstitials in a crystal lattice. Non-destructive testing , NDT, is a very broad group of structural or material inspections and as the name implies, these inspections do not destroy the material/structure being examined. Key mechanical design properties are: Stiffness . Stiffness is the ability of an object to resist deformation in response to an applied force. Strength . Strength is the ability of a material to resist deformation. Hardness . Hardness is the ability to withstand surface indentation and scratching. Ductility . Ductility is the ability of a material to deform under tensile load (% elongation). Toughness . Toughness is the ability of a material to absorb energy (or withstand shock) and plastically deform without fracturing. Pure metal is a material (usually solid) comprising one metallic element (e.g., iron, aluminum, copper, chromium, titanium, gold, nickel). An alloy is a mixture of two or more materials, at least one of which is a metal. Alloys can have a microstructure consisting of solid solutions, where secondary atoms are introduced as substitutionals or interstitials in a crystal lattice. Steels are iron–carbon alloys that may contain appreciable concentrations of other alloying elements. This question has no answer. There is no material perfect for all purposes. In most cases, engineers must take into account all their mechanical and thermal properties. Some materials must withstand high temperatures, some not. There are some advanced materials like titanium alloys, but these materials are so expensive that can be used only in reasonable cases. Basis of Materials Science What are atoms?

The atoms are defined as the smallest constituents of ordinary matter, which can be divided without the release of electrically charged particles. The atoms consist of two parts. An atomic nucleus and an electron cloud . The physical world is composed of combinations of various subatomic or fundamental particles . These are the smallest building blocks of matter. The atoms consist of two parts. An atomic nucleus and an electron cloud . The number of electrons and their arrangement in the electron cloud is responsible for the chemical behavior of atoms. The nuclear properties (atomic mass, nuclear cross-sections) of the element are determined by the number of protons (atomic number) and number of neutrons (neutron number). Nuclear stability is a concept that helps to identify the stability of an isotope. To identify the stability of an isotope it is needed to find the ratio of neutrons to protons. To determine the stability of an isotope you can use the ratio neutron/proton (N/Z). There are only certain combinations of neutrons and protons, which forms stable nuclei . Unstable nuclei must undergo nuclear decay (radioactive decay) to stabilize itself, it is a random and natural process. The number of atoms in 1 mole (e.g. 12 grams of carbon) of a substance is equal to the Avogadro’s constant , which is equal to 6.022 x 10 23 . The atoms are about 10 – 10 meters (or 10 – 8 centimeters) in size, which corresponds to the angstrom. The ångström is not a part of the SI system of units, but it can be considered part of the metric system in general. The volume of an atom is about 15 orders of magnitude larger than the volume of a nucleus. For uranium atom , the Van der Waals radius is about 186 pm = 1.86 ×10 −10 m . It must be noted, atoms lack a well-defined outer boundary. The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus. However, this assumes the atom to exhibit a spherical shape, which is only obeyed for atoms in vacuum or free space. Therefore, there are various non-equivalent definitions of atomic radius. Van der Waals radius. In principle, Vana der Waals radius is half the minimum distance between the nuclei of two atoms of the element that are not bound to the same molecule. Ionic radius. An ionic radius is one-half the distance between the nuclei of two ions in an ionic bond. Covalent radius. Covalent radius is the nominal radius of the atoms of an element when covalently bound to other atoms. Metallic radius. A metallic radius is one-half the distance between the nuclei of two adjacent atoms in a crystalline structure, when joined to other atoms by metallic bonds. Why are atoms radioactive? Atomic nuclei consist of protons and neutrons, which attract each other through the nuclear force , while protons repel each other via the ele c tric force due to their positive charge. These two forces compete, leading to various stability of nuclei. There are only certain combinations of neutrons and protons, which forms stable nuclei . Neutrons stabilize the nucleus , because they attract each other and protons , which helps offset the electrical repulsion between protons. As a result, as the number of protons increases, an increasing ratio of neutrons to protons is needed to form a stable nucleus. If there are too many or too few neutrons for a given number of protons, the resulting nucleus is not stable and it undergoes radioactive decay. Unstable isotopes decay through various radioactive decay pathways, most commonly alpha decay, beta decay, or electron capture. Many other rare types of decay, such as spontaneous fission or neutron emission are known. It should be noted that all of these decay pathways may be accompanied by the subsequent emission of gamma radiation . Pure alpha or beta decays are very rare. What are the 4 types of radiation? Ionizing radiation has different ionization mechanisms, and may be grouped as: Directly ionizing . Charged particles ( atomic nuclei, electrons, positrons, protons, muons, etc. ) can ionize atoms directly by fundamental interaction through the Coulomb force if it carries sufficient kinetic energy. Alpha radiation . Alpha radiation consist of alpha particles at high energy/speed. The production of alpha particles is termed alpha decay . Beta radiation . Beta radiation consist of free electrons or positrons at relativistic speeds. The production of beta particles is termed beta decay . Indirectly ionizing . Indirect ionizing radiation is electrically neutral particles and therefore does not interact strongly with matter. Photon radiation ( Gamma rays or X-rays ). Photon radiation consist of high energy photons . According to the currently valid definition, X-rays are emitted by electrons outside the nucleus, while gamma rays are emitted by the nucleus . The production of gamma rays is termed gamma decay . Neutron radiation . Neutron radiation consist of free neutrons at any energies/speeds. This type of radiation can be produced by nuclear reactors or in flight, neutrons contribute 40 – 80% of the equivalent dose. Directly ionizing . Charged particles ( atomic nuclei, electrons, positrons, protons, muons, etc. ) can ionize atoms directly by fundamental interaction through the Coulomb force if it carries sufficient kinetic energy. Alpha radiation . Alpha radiation consist of alpha particles at high energy/speed. The production of alpha particles is termed alpha decay . Beta radiation . Beta radiation consist of free electrons or positrons at relativistic speeds. The production of beta particles is termed beta decay . Alpha radiation . Alpha radiation consist of alpha particles at high energy/speed. The production of alpha particles is termed alpha decay . Beta radiation . Beta radiation consist of free electrons or positrons at relativistic speeds. The production of beta particles is termed beta decay . Indirectly ionizing . Indirect ionizing radiation is electrically neutral particles and therefore does not interact strongly with matter. Photon radiation ( Gamma rays or X-rays ). Photon radiation consist of high energy photons . According to the currently valid definition, X-rays are emitted by electrons outside the nucleus, while gamma rays are emitted by the nucleus . The production of gamma rays is termed gamma decay . Neutron radiation . Neutron radiation consist of free neutrons at any energies/speeds. This type of radiation can be produced by nuclear reactors or in flight, neutrons contribute 40 – 80% of the equivalent dose. Photon radiation ( Gamma rays or X-rays ). Photon radiation consist of high energy photons . According to the currently valid definition, X-rays are emitted by electrons outside the nucleus, while gamma rays are emitted by the nucleus . The production of gamma rays is termed gamma decay . Neutron radiation . Neutron radiation consist of free neutrons at any energies/speeds. This type of radiation can be produced by nuclear reactors or in flight, neutrons contribute 40 – 80% of the equivalent dose. About Materials Properties Materials science and engineering is interdisciplinar and very important branch of study, which deals with the design and discovery of new materials, particularly solids. Materials science is one of the oldest forms of engineering and applied science and The material of choice of a given era is often a defining point (e.g. Stone Age, Bronze Age, Iron Age). The intellectual origins of materials science stem from the Enlightenment, when researchers began to use analytical thinking from chemistry, physics, and engineering to understand ancient, phenomenological observations in metallurgy and mineralogy. Sometimes it is useful to subdivide the discipline of materials science and engineering into materials science and materials engineering subdisciplines. The discipline of materials science involves investigating the relationships that exist between the structures and properties of materials. In contrast, materials engineering is, on the basis of these structure–property correlations, designing or engineering the structure of a material to produce a predetermined set of properties. Material properties are intensive properties , that means they are independent of the amount of mass and may vary from place to place within the system at any moment. The basis of materials science involves studying the structure of materials, and relating them to their properties (mechanical, electrical etc.). Once a materials scientist knows about this structure-property correlation, they can then go on to study the relative performance of a material in a given application. The major determinants of the structure of a material and thus of its properties are its constituent chemical elements and the way in which it has been processed into its final form. About This Project Main purpose of this project is to help the public to learn some interesting and important information about chemical elements and many common materials. We realize that the basics in the materials science can help people to understand many common problems. Anyone can be able to come here, learn the basics of materials science , material properties and to compare these properties. Feel free to ask a question, leave feedback or take a look at one of our articles. Properties of chemical elements Periodic Table in 8K resolution