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Binder (material)
A binder or binding agent is any material or substance that holds or draws other materials together to form a cohesive whole mechanically, chemically, by adhesion or cohesion. More narrowly, binders are liquid or dough-like substances that harden by a chemical or physical process and bind fibres, filler powder and other particles added into it. Examples include glue, adhesive and thickening. Examples of mechanical binders are bond stones in masonry and tie beams in timber framing. Classification Binders are loosely classified as organic ( bitums, animal and plant glues, polymers) and inorganic ( lime, cement, gypsum, liquid glass, etc.). These can be either metallic or ceramic as well as polymeric depending on the nature of the main material. For example, in the compound WC-Co (Tungsten Carbide used in cutting tools) Co constitutes the binding agent for the WC particles. Based on their chemical resistance, binders are classified by the field of use: non-hydrau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion
Adhesion is the tendency of dissimilar particles or interface (matter), surfaces to cling to one another. (Cohesion (chemistry), Cohesion refers to the tendency of similar or identical particles and surfaces to cling to one another.) The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Surface energy Surface energy is conventionally defined as the work (physics), work that is required to build an area of a particular surface. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy γ of each surface is equal to h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portland Cement
Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar (masonry), mortar, stucco, and non-specialty grout. It was developed from other types of hydraulic lime in England in the early 19th century by Joseph Aspdin, and is usually made from limestone. It is a fine powder (substance), powder, produced by heating limestone and clay minerals in a kiln to form Clinker (cement), clinker, and then #Cement grinding, grinding the clinker with the addition of several percent (often around 5%) gypsum. Several types of portland cement are available. The most common, historically called ordinary portland cement (OPC), is grey, but white portland cement is also available. The cement was so named by Joseph Aspdin, who obtained a patent for it in 1824, because, once hardened, it resembled the fine, pale limestone known as Portland stone, quarried from the windswept cliffs of the Isle of Portland in Dorset. Portland stone was p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Material
A composite or composite material (also composition material) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Composite materials with more than one distinct layer are called ''composite laminates''. Typical engineered composite materials are made up of a binding agent forming the ''matrix'' and a Filler (materials), filler material (particulates or fibres) giving ''substance'', e.g.: * Concrete, reinforced concrete and masonry with cement, lime or Mortar (masonry), mortar (which is itself a composite material) as a binder * Composite wood such as glulam and plywood with wood glue as a binder * Reinforced plastics, such as fiberglass and fibre-rein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compression (physics)
In mechanics, compression is the application of balanced inward ("pushing") forces to different points on a material or Structural system, structure, that is, forces with no Net force, net sum or torque directed so as to reduce its size in one or more directions.Ferdinand Pierre Beer, Elwood Russell Johnston, John T. DeWolf (1992), "Mechanics of Materials". (Book) McGraw-Hill Professional, It is contrasted with tension (physics), tension or traction, the application of balanced outward ("pulling") forces; and with shear stress, shearing forces, directed so as to displace layers of the material parallel to each other. The compressive strength of materials and structures is an important engineering consideration. In uniaxial compression, the forces are directed along one direction only, so that they act towards decreasing the object's length along that direction. The compressive forces may also be applied in multiple directions; for example inwards along the edges of a plate or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resin
A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Common resins include amber, hashish, frankincense, myrrh and the animal-derived resin, shellac. Resins are used in varnishes, adhesives, food additives, incenses and perfumes. Resins protect plants from insects and pathogens, and are secreted in response to injury. Resins repel herbivores, insects, and pathogens, while the volatile natural phenol, phenolic compounds may attract benefactors such as predators of insects that attack the plant. Composition Most plant resins are composed of terpenes. Specific components are alpha-Pinene, alpha-pinene, pinene, beta-pinene, carene, delta-3 carene, and sabinene, the monocyclic terpenes limonene and terpinolene, and smaller amounts of the tricyclic sesquiterpenes, longifolene, caryophyllene, and cad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shear Force
In solid mechanics, shearing forces are unaligned forces acting on one part of a Rigid body, body in a specific direction, and another part of the body in the opposite direction. When the forces are Collinearity, collinear (aligned with each other), they are called ''tension forces'' or ''compression forces''. Shear force can also be defined in terms of Plane (geometry), planes: "If a plane is passed through a body, a force acting along this plane is called a ''shear force'' or ''shearing force''." Force required to shear steel This section calculates the force required to cut a piece of material with a shearing action. The relevant information is the area of the material being sheared, i.e. the area across which the shearing action takes place, and the shear strength of the material. A round bar of steel is used as an example. The shear strength is calculated from the tensile strength using a factor which relates the two strengths. In this case 0.6 applies to the example steel, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (physics)
Tension is the pulling or stretching force transmitted axially along an object such as a string, rope, chain, rod, truss member, or other object, so as to stretch or pull apart the object. In terms of force, it is the opposite of ''compression''. Tension might also be described as the action-reaction pair of forces acting at each end of an object. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitting tension will exert forces on the objects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rebar
Rebar (short for reinforcement bar or reinforcing bar), known when massed as reinforcing steel or steel reinforcement, is a tension device added to concrete to form ''reinforced concrete'' and reinforced masonry structures to strengthen and aid the concrete under tension. Concrete is strong under compression, but has low tensile strength. Rebar usually consists of steel bars which significantly increase the tensile strength of the structure. Rebar surfaces feature a continuous series of ribs, lugs or indentations to promote a better bond with the concrete and reduce the risk of slippage. The most common type of rebar is carbon steel, typically consisting of hot-rolled round bars with deformation patterns embossed into its surface. Steel and concrete have similar coefficients of thermal expansion, so a concrete structural member reinforced with steel will experience minimal differential stress as the temperature changes. Other readily available types of rebar are manufacture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tensile Strength
Ultimate tensile strength (also called UTS, tensile strength, TS, ultimate strength or F_\text in notation) is the maximum stress that a material can withstand while being stretched or pulled before breaking. In brittle materials, the ultimate tensile strength is close to the yield point, whereas in ductile materials, the ultimate tensile strength can be higher. The ultimate tensile strength is usually found by performing a tensile test and recording the engineering stress versus strain. The highest point of the stress–strain curve is the ultimate tensile strength and has units of stress. The equivalent point for the case of compression, instead of tension, is called the compressive strength. Tensile strengths are rarely of any consequence in the design of ductile members, but they are important with brittle members. They are tabulated for common materials such as alloys, composite materials, ceramics, plastics, and wood. Definition The ultimate tensile strength ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compressive Strength
In mechanics, compressive strength (or compression strength) is the capacity of a material or Structural system, structure to withstand Structural load, loads tending to reduce size (Compression (physics), compression). It is opposed to ''tensile strength'' which withstands loads tending to elongate, resisting Tension (physics), tension (being pulled apart). In the study of strength of materials, compressive strength, tensile strength, and shear strength can be analyzed independently. Some materials fracture at their compressive strength limit; others Plasticity (physics), deform irreversibly, so a given amount of Deformation (engineering), deformation may be considered as the limit for compressive load. Compressive strength is a key value for Structural engineering, design of structures. Compressive strength is often measured on a universal testing machine. Measurements of compressive strength are affected by the specific test method and conditions of measurement. Compressive s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Silicate
Calcium silicate can refer to several silicates of calcium including: *CaO·SiO2, wollastonite (CaSiO3) *2CaO·SiO2, larnite (Ca2SiO4) *3CaO·SiO2, alite or (Ca3SiO5) *3CaO·2SiO2, (Ca3Si2O7). This article focuses on Ca2SiO4, also known as calcium orthosilicate, or by the shortened trade name Cal-Sil/Calsil. All calcium silicates are white free-flowing powders. Being strong, cheap and nontoxic, they are components of important structural materials. Production and occurrence Calcium silicates are produced by treating calcium oxide and silicon dioxide, silica in various ratios. Their formation is relevant to Portland cement. Calcium silicate is a byproduct of the Pidgeon process, a major route to magnesium metal. The process converts a mixture of magnesium and calcium oxides as represented by the following simplified equation: : The calcium oxide combines with silicon as the oxygen scavenger, yielding the very stable calcium silicate and releasing volatile (at high temperatures) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autoclave
An autoclave is a machine used to carry out industrial and scientific processes requiring elevated temperature and pressure in relation to ambient pressure and/or temperature. Autoclaves are used before surgical procedures to perform sterilization and in the chemical industry to cure coatings and vulcanize rubber and for hydrothermal synthesis. Industrial autoclaves are used in industrial applications, especially in the manufacturing of composites. Many autoclaves are used to sterilize equipment and supplies by subjecting them to pressurized saturated steam at for 30–60 minutes at a gauge pressure of 103 kPa depending on the size of the load and the contents. The autoclave was invented by Charles Chamberland in 1879, although a precursor known as the steam digester was created by Denis Papin in 1679. The name comes from Greek ''auto-'', ultimately meaning self, and Latin ''clavis'' meaning key, thus a self-locking device. Uses Sterilization autoclaves are widely us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
