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Carbonitriding
Carbonitriding is a metallurgical surface modification technique that is used to increase the surface hardness of a metal, thereby reducing wear. During the process, atoms of carbon and nitrogen diffuse interstitially into the metal, creating barriers to slip, increasing the hardness and modulus near the surface. Carbonitriding is often applied to inexpensive, easily machined low carbon steel to impart the surface properties of more expensive and difficult to work grades of steel. Surface hardness of carbonitrided parts ranges from 55 to 62 HRC. Certain pre-industrial case hardening processes include not only carbon-rich materials such as charcoal, but nitrogen-rich materials such as urea, which implies that traditional surface hardening techniques were a form of carbonitriding. Process Carbonitriding is similar to gas carburization with the addition of ammonia to the carburizing atmosphere, which provides a source of nitrogen. Nitrogen is absorbed at the surface and diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Case Hardening
Case-hardening or surface hardening is the process of hardening the surface of a metal object while allowing the metal deeper underneath to remain soft, thus forming a thin layer of harder metal at the surface. For iron or steel with low carbon content, which has poor to no hardenability of its own, the case-hardening process involves infusing additional carbon or nitrogen into the surface layer. Case-hardening is usually done after the part has been formed into its final shape, but can also be done to increase the hardening element content of bars to be used in a pattern welding or similar process. The term face hardening is also used to describe this technique, when discussing modern armour. Hardening is desirable for metal components that are subject to sliding contact with hard or abrasive materials, as the hardened metal is more resistant to surface wear. However, because hardened metal is usually more brittle than softer metal, through-hardening (that is, hardening the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitridization
Nitriding is a heat treating process that diffuses nitrogen into the surface of a metal to create a case-hardened surface. These processes are most commonly used on low-alloy steels. They are also used on titanium, aluminium and molybdenum. Typical applications include gears, crankshafts, camshafts, cam followers, valve parts, extruder screws, die-casting tools, forging dies, extrusion dies, firearm components, injectors and plastic-mold tools. Processes The processes are named after the medium used to donate. The three main methods used are: ''gas nitriding'', ''salt bath nitriding'', and ''plasma nitriding''. Gas nitriding In gas nitriding the donor is a nitrogen-rich gas, usually ammonia (NH3), which is why it is sometimes known as ''ammonia nitriding''. When ammonia comes into contact with the heated work piece it dissociates into nitrogen and hydrogen. The nitrogen then diffuses onto the surface of the material creating a nitride layer. This process has existed for nea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carburizing
Carburising, carburizing (chiefly American English), or carburisation is a heat treatment process in which iron or steel absorbs carbon while the metal is heated in the presence of a carbon-bearing material, such as charcoal or carbon monoxide. The intent is to make the metal harder. Depending on the amount of time and temperature, the affected area can vary in carbon content. Longer carburizing times and higher temperatures typically increase the depth of carbon diffusion. When the iron or steel is cooled rapidly by quenching, the higher carbon content on the outer surface becomes hard due to the transformation from austenite to martensite, while the core remains soft and tough as a ferritic and/or pearlite microstructure.Oberg, E., Jones, F., and Ryffel, H. (1989) ''Machinery's Handbook 23rd Edition.'' New York: Industrial Press Inc. This manufacturing process can be characterized by the following key points: It is applied to low-carbon workpieces; workpieces are in contact w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitriding
Nitriding is a heat treating process that diffuses nitrogen into the surface of a metal to create a case-hardened surface. These processes are most commonly used on low-alloy steels. They are also used on titanium, aluminium and molybdenum. Typical applications include gears, crankshafts, camshafts, cam followers, valve parts, extruder screws, die-casting tools, forging dies, extrusion dies, firearm components, injectors and plastic-mold tools. Processes The processes are named after the medium used to donate. The three main methods used are: ''gas nitriding'', ''salt bath nitriding'', and ''plasma nitriding''. Gas nitriding In gas nitriding the donor is a nitrogen-rich gas, usually ammonia (NH3), which is why it is sometimes known as ''ammonia nitriding''. When ammonia comes into contact with the heated work piece it dissociates into nitrogen and hydrogen. The nitrogen then diffuses onto the surface of the material creating a nitride layer. This process has existed for nearly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computerised Heat Treatment Furnance
Computerize may refer to: * Computerization: equipping something with or the usage of and associated automation by computers and software * Business process reengineering that converts a manual process into one done by a computer * Digital transformation of a service or business * Equipping with a general purpose computer, embedded computer, or computer system * Inputting data (computing) into computers * Digitizing DigitizationTech Target. (2011, April). Definition: digitization. ''WhatIs.com''. Retrieved December 15, 2021, from https://whatis.techtarget.com/definition/digitization is the process of converting information into a digital (i.e. computer- ... information for computers * Creating computer-generated content See also * * {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatigue (material)
In materials science, fatigue is the initiation and propagation of cracks in a material due to cyclic loading. Once a fatigue crack has initiated, it grows a small amount with each loading cycle, typically producing striations on some parts of the fracture surface. The crack will continue to grow until it reaches a critical size, which occurs when the stress intensity factor of the crack exceeds the fracture toughness of the material, producing rapid propagation and typically complete fracture of the structure. Fatigue has traditionally been associated with the failure of metal components which led to the term metal fatigue. In the nineteenth century, the sudden failing of metal railway axles was thought to be caused by the metal ''crystallising'' because of the brittle appearance of the fracture surface, but this has since been disproved. Most materials, such as composites, plastics and ceramics, seem to experience some sort of fatigue-related failure. To aid in predicting t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Engineering
Surface engineering is the sub-discipline of materials science which deals with the surface of solid matter. It has applications to chemistry, mechanical engineering, and electrical engineering (particularly in relation to semiconductor manufacturing). Solids are composed of a bulk material covered by a surface. The surface which bounds the bulk material is called the surface phase. It acts as an interface to the surrounding environment. The bulk material in a solid is called the bulk phase. The surface phase of a solid interacts with the surrounding environment. This interaction can degrade the surface phase over time. Environmental degradation of the surface phase over time can be caused by wear, corrosion, fatigue and creep. Surface engineering involves altering the properties of the surface phase in order to reduce the degradation over time. This is accomplished by making the surface robust to the environment in which it will be used. It provides a cost-effective mater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quench Polish Quench
Quench polish quench (QPQ) is a specialized type of nitrocarburizing case hardening that increases corrosion resistance. It is sometimes known by the brand name of Tufftride, Tenifer or Melonite. Three steps are involved: nitrocarburize ("quench"), polish, and post-oxidize ("quench"). This process is often used when two or more of the following properties are required in a workpiece: * wear resistance * corrosion resistance * lubricity * fatigue strength Common applications of the process are for piston rods of shock absorbers, cylinders and rods for hydraulic systems, pumps, axles, spindle (tool), spindles, firearm slides and barrels and valves. Process The process starts with a standard salt bath nitrocarburizing cycle, which produces a layer of ε iron nitride. Next, the workpiece is mechanically polished; typical polishing processes include vibratory finishing, lapping, and centerless grinding. Finally, the workpiece is re-immersed into the salt quench bath for 20 to 30 mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Differential Hardening
Differential heat treatment (also called selective heat treatment or local heat treatment) is a technique used during heat treating to harden or soften certain areas of a steel object, creating a difference in hardness between these areas. There are many techniques for creating a difference in properties, but most can be defined as either ''differential hardening'' or ''differential tempering''. These were common heat treating techniques used historically in Europe and Asia, with possibly the most widely known example being from Japanese swordsmithing. Some modern varieties were developed in the twentieth century as metallurgical knowledge and technology rapidly increased. Differential hardening consists of either two methods. It can involve heating the metal evenly to a red-hot temperature and then cooling it at different rates, turning part of the object into very hard martensite while the rest cools slower and becomes softer pearlite. It may also consist of heating only a part of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Die (manufacturing)
A die is a specialized machine tool used in manufacturing industries to cut and/or form material to a desired shape or profile. Stamping dies are used with a press, as opposed to drawing dies (used in the manufacture of wire) and casting dies (used in molding) which are not. Like molds, dies are generally customized to the item they are used to create. Products made with dies range from simple paper clips to complex pieces used in advanced technology. Continuous-feed laser cutting may displace the analogous die-based process in the automotive industry, among others. Die stamping Blanking and piercing are two die cutting operations, and bending is an example of a die forming operation. Die forming Forming operations work by deforming materials like sheet metal or plastic using force (compression, tension, or both) and rely on the material's mechanical properties. Forming dies are typically made by tool and die makers and put into production after mounting into a press. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tool
A tool is an object that can extend an individual's ability to modify features of the surrounding environment or help them accomplish a particular task. Although many animals use simple tools, only human beings, whose use of stone tools dates back hundreds of millennia, have been observed using tools to make other tools. Early human tools, made of such materials as stone, bone, and wood, were used for preparation of food, hunting, manufacture of weapons, and working of materials to produce clothing and useful artifacts. The development of metalworking made additional types of tools possible. Harnessing energy sources, such as animal power, wind, or steam, allowed increasingly complex tools to produce an even larger range of items, with the Industrial Revolution marking an inflection point in the use of tools. The introduction of widespread automation in the 19th and 20th centuries allowed tools to operate with minimal human supervision, further increasing the productivity of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Machinery
Hydraulic machines use liquid fluid power to perform work. Heavy construction vehicles are a common example. In this type of machine, hydraulic fluid is pumped to various hydraulic motors and hydraulic cylinders throughout the machine and becomes pressurized according to the resistance present. The fluid is controlled directly or automatically by control valves and distributed through hoses, tubes, or pipes. Hydraulic systems, like pneumatic systems, are based on Pascal's law which states that any pressure applied to a fluid inside a closed system will transmit that pressure equally everywhere and in all directions. A hydraulic system uses an incompressible liquid as its fluid, rather than a compressible gas. The popularity of hydraulic machinery is due to the very large amount of power that can be transferred through small tubes and flexible hoses, the high power density and a wide array of actuators that can make use of this power, and the huge multiplication of forces t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
