Allowance (Tolerance): The clearance specified by the foundry, the difference of limit dimensions, such as the maximum or minimum interference between mating parts calculated by arithmetic.
Alloy: A metal substance composed of two or more chemical elements, containing at least one metal element, usually different from the characteristics of the components.
Alloy Steel: In addition to carbon, steel also contains a large number of alloying elements, as well as recognized content of phosphorus, sulfur, manganese, and silicon.
Alpha – ferrite: Body-centered cubic pure iron with stable properties below 1670°F (910°C).
Alpha Martensite: A form of martensite. In general, it may represent the most twisted and the least developed phase of the transformation from austenite to martensitic at room temperature.
Ambient Temperature: The temperature of the ambient air.
Annealing: The parts are heated to and maintained at a suitable temperature, then cooled at an appropriate rate, so as to change the physical or chemical properties of the parts and reduce the hardness.
Anticarburizing Compounds: Anti-carbonization compounds applied to metal surface.
Acceptable Quality Level.
The level of quality established on a pre-arranged inspection system using randomly selected samples.
Argon Oxygen Decarburization (AOD): A process that can improve the cleanliness of metals and obtain excellent mechanical properties. The principle is to inject argon, oxygen, and nitrogen into molten steel for secondary refining.
Artificial Aging: An aging treatment carried out above normal temperature.
As Cast (as-cast, u.m.): It refers to the metal without surface treatment (except sandblasting or gate removal) or any type of treatment (including post-casting heat treatment).
ASM: American Society for Metals.
ASNT: American Society for Nondestructive Testing.
Austenite: Known as gamma iron, it is the face-centered cubic stage of steel and iron. It represents a solid solution in steel, and gamma iron is the solvent.
Austenite Steel: Any steel containing adequate alloy that can generate a steady austenitic (gamma iron) crystal structure at normal temperature.
Reverse taper in the design direction of extraction from the pattern or core box;
Prevents removal of the pattern from the mold without damaging the mold.
A large amount of sand in a long-necked vase. The sand is compacted onto the face sand that covers the pattern.
Batch: The amount or quantity of core or mold sand or any other material prepared at one time.
Batch Oven: Oven used to bake a bulk number of cores at one time.
Bead: Half-round cavity in a mold, or half-round projection or molding on a casting, a single deposit of weld metal produced by fusion.
BHN: Brinell Hardness Number.
Bimetal: Casting, usually centrifugal casting, made of two different metals, then fused together.
A binder used as an additive to molded or core sand to impart strength or plasticity in the “green” or dry state.
Blacking Carbon: Carbonaceous materials such as plumbago, graphite or powdered coke usually mixed with a binder and frequently carried in suspension in water or other liquid; used as an additive in the mold flux to improved casting finish.
Blasting (Blast Cleaning): The finishing process for cleaning ornamental objects by an air blast or centrifugal wheel that removes abrasive particles against the surface of the workpieces. Small, irregular parts of steel or iron are used as the abrasive in grit blasting, and steel or iron balls in shot blasting.
The riser is not in contact with the atmosphere or does not reach the outside of the mold.
Blister: Blisters, the variant of blowholes, are the shallow blow with a thin film of the metal over it.
Casting defects caused by gas trapped in molten or partially molten metal.
Boil: Agitation of a bath of metal caused by the liberation of a gas beneath its surface. May be deliberately induced by the addition of oxidizing material to a bath containing excess carbon. In the later case it is called a carbon boil and CO or CO2 are liberated.
Bond: Bonding substance or bonding agents – any material other than water, which, when added to foundry sands, imparts bond strength.The overlapping of brick to give both longitudinal and transverse strength.
Bond Strength: Property of a foundry sand to offer deformation resistance. In chemistry, as the strength with which a chemical bond holds two atoms together.
Boring: A machining method uses a stationary, non-rotating cutting tool to remove material from a workpiece.
Boss (Pad): Integral features added to a casting, for a number of potential functions, like mounting. Usually intended for drilling and tapping for attaching parts.
Bottom Running or Pouring: Filling the mold cavity from the bottom by means of gates from the runner.
Bright Annealing: A heat treatment process carried out under a nitrogen-hydrogen atmosphere, so surface does not oxidize, remaining bright.
Brinell Hardness: It indicates the ability of a metal to resist permanent indentation deformation. The value of hardness of a metal on an arbitrary scale representing kg/mm², calculated by measuring the diameter of the impression made by a ball of given diameter applied under a known load. Values are expressed in Brinell Hardness Numbers, BHN.
Brittle Fracture: Fracture of a metallic object or other material without appreciable prior plastic deformation.
Indentation in the casting due to expansion of the sand, which can be called the beginning of expansion defects.
Bulk Density: The ratio of the weight of a material to its total volume (including any inherent porosity).
Burnt-On-Sand: A misnomer usually indicating the mixture of sand and metal on the surface of a casting due to metal penetration of the sand mold. It mainly occurs in think-walled, heavy castings or at the points with the highest temperatures.
Burnishing: Developing a smooth finish and micro-hardness by tumbling or rubbing metal with a small hard tool to compact the surface.
CAE: Computer Aided Engineering.
Carbide: A carbide is a compound composed of carbon and a less electronegative element.
Carbon: Element in the form of diamond and graphite. When heated together with the latter, carbon can reduce many metals from oxides, and a small amount of carbon can greatly affect the properties of iron. It is nonmetallic and tetravalent–making four electrons available to form covalent chemical bonds. Though classed as a nonmetallic, metallurgically, like boron, it is treated as a metal.
Carbonitriding (Nicarbing) : A process of surface hardening of an iron alloy by heating the alloy in a gas atmosphere that simultaneously absorbs carbon and nitrogen, and then cooling it at a rate that can produce the required properties.
Carburizing: A form of surface hardening in which an inward carbon gradient is generated from the surface, and the surface layer is hardened by directly quenching from the carbonization temperature or cooling to room temperature, and then re-austenitizing and quenching.
Case Hardening: The process of hardening the iron alloy makes the surface or case much harder than the inside or core. Typical surface hardening process are carburizing, carbonitriding and nitriding.
Casting Layout: The dimensions are checked against applicable drawings and specifications.
Cavitation: The formation and collapse of cavities or bubbles within a liquid.
Cementite: A compound of iron and carbon, usually called iron carbide, has a similar chemical structure, Fe3C. The characteristic of cementite is the orthorhombic structure.
Centrifugal Casting: Castings made in rotating molds generate centrifugal force in the molten metal.
Chaplet: A small metal insert or spacer used to support a mold core during the casting process.
Charge: A certain weight of metal injected into the furnace.
Charpy Impact Test: A pendulum single-click impact test. In this test, the sample is usually notched, and the two ends are supported as simple beams and broken by a falling pendulum.
The energy absorbed during fracture, such as impact strength or notch toughness.
Chill (External): Add metal, graphite or carbon blocks to the mold or core to locally increase the heat dissipation rate during the solidification process and reduce shrinkage defects.
Chill (Internal): A metal device/insert located on the surface of the casting or in the mold or core inside the mold to increase the heat dissipation rate, including directional solidification and reduction of shrinkage defects.The internal cooling may become part of the casting.
Choke: A restriction in the pouring system that controls the flow of metal into the mold cavity.
Cleaning: Remove runners, risers, burrs, excess metal and sand from the casting.
Close Over: The operation of lowering a part of the mold over some protruding part (such as a core).
CMM: Coordinate Measuring Machine.
CNC: Computer Numerical Controlled Machine Tools.
Coefficient of Expansion: An increase in unit size due to an increase in unit temperature. Measurement is in inches per degree Fahrenheit (in/in/1/2°F) or millimeters per millimeter per Celsius (mm/mm/1/2°C).
Cohesion: The force that brings similar particles together. It varies for different metals and depends on the molecular arrangement after heat treatment.
Coining: Straighten and sizing castings by molding method. A process for shaping metal.
Cold Box Process:
Cold Cracking: Cracks in cold or near-cold metal due to excessive internal stress caused by shrinkage.
It is often caused by too hard mold or inappropriate casting design.
Cold Lap: Wrinkles on the surface of ingots or castings due to initial freezing.
Cold Shot: A small ball of metal embedded in a casting but not completely melted.
Cold Shut: Casting defects are caused by incomplete melting or discontinuity due to the accumulation of molten metal in the mold from the opposite direction or due to surface folding. It may have the appearance of cracks or seams, with smooth and rounded edges.
Cold Work: Plastic deformation of metals at room temperature. Strength and hardness may increase substantially.
Cold-Box Process: Any core binder process that uses gas or vaporization catalyst to cure coated sand at room temperature.
Collapsibility: In the casting process, the sand mixture is required to decompose under pressure and temperature in order to avoid thermal cracking or promote the separation of sand and castings.
Color Etching: A kind of micro-etching produced by forming a thin film from a certain metal compound.
Columnar Structure: A coarse structure of parallel crystal columns caused by highly directional solidification.
Compression Test: A static load is applied to the small cylindrical test piece to determine its compressive strength in pounds per sq.in.
Compressive Strength (Yield): The maximum stress that can be withstood without plastic deformation or damage.
Conduction: The transfer of heat, sound, etc., is transferred from one particle to another through energy.
Conductivity (Thermal): The amount of heat that passes through a material, measured per unit time, unit cross-sectional area, and unit length, (electricity) is the amount of electricity transferred through a material with a known cross-sectional area and length.
Constituent: The distinguishable part of the microscopic image of the alloy or mixture.
Contamination: The presence of a small amount of harmful elements in the alloy adversely affects the mechanical properties of the alloy or the integrity of the casting.
Contraction: The volume change of metals (except antimony and bismuth) and alloys when they solidify and cool to room temperature.
Contraction Cracks: Cracks caused by the restriction of metal shrinkage in the mold. It may occur after solidification (called hot tearing) or a short time after the casting is removed from the mold.
Controlled Atmosphere: Any gas or mixture of gases that prevents or retards oxidation and decarburization.
Convection: The movement of the fluid occurs due to the difference in density. In heat transfer, this meaning has been extended to include forced and natural movement or circulation.
Converter: A furnace in which a gas, usually air, is blown through a molten pool or coarse metal to oxidize impurities.
A curve showing the relationship between time and temperature of a metal sample during solidification and cooling.
Since most phase transitions involve the evolution or absorption of heat, the slope of the curve may have abrupt changes.
Cooling, Controlled: The cooling process from a predetermined temperature is used to produce the required tissue to avoid hardening, cracking or internal damage.
Cope: The upper or top part of a flask, mold, or pattern.
Core: A kind of finished sand, embedded in the mold, used to mold the inside of the casting or the part that cannot be molded by the mold.
Core assembly: A collection of many cores.
Core Binder: Any material used to hold the core sand particles together.
Core Blow: The air pockets in the casting near the core cavity are caused by gas trapped in the core cavity.
Core Box, Combination: The pattern of the core box and the core dryer are the same. Half of them are used as half-core boxes and half-core dryers.
Core Compound: A commercial mixture used as a core sand binder.
Core Fin: Casting defects, depressions in the cast, caused by fins not being removed from the cast before the cast is set, or by paste oozing from the joint.
Core Float: A casting defect caused by the buoyancy of a steel core in steel water causing the core to move toward the shell surface of the mold, resulting in a deviation from the intended wall thickness.
Core Hardness: The core’s ability to resist scratches or abrasion.
Coreprint: The projection on the pattern that leaves the impression of the support core on the mold.
Core Sand: The sand used to make the core is added with binding material to make it have good cohesion and permeability after drying. Usually the clay content is low.
Core Shift: Due to changes in the position of the core or misalignment of the core during assembly, the specified size of the core segment changes.
Core Vents: In a core blowing machine, a metal mesh or slotted piece used to form the vent of the core box.
Core wash: A liquid suspension made of refractory material, applied to the core and dried (for improving the surface of the casting).
The composition changes due to the solidification characteristics of the alloy.
Usually these compositional differences occur on the microscopic scale, and the distance between the extreme compositions is controlled by the solidified structure of the alloy.
Corrosion: The chemical attack of the furnace lining by gases, slag, ash or other fluxes generated in various smelting processes.
Corrosion Index: A number representing the maximum depth of corrosion breakdown within a year, in mils, based on a linear extrapolation of the breakdown that occurred during a given test or service life.
Corrosion Wear: Wear that reacts chemically or electrochemically with the environment.
Cover: A protective layer laid on the melt to exclude the oxidizing atmosphere and prevent its ignition in the case of magnesium. The neutral cover simply protects the metal from the atmosphere; The reaction cover layer contains an agent such as a deoxidizer.
Cover Core: A core set in the process of stamping the mold to cover and complete the cavity formed by retracting the loose part of the mold. It is also used to form part or all of the concave surface of the mold cavity. Place the core on top of another core to create a flat parting line.
Crack, Hot Tear: When the casting is at the solidification temperature or slightly lower than the solidification temperature, the soft metal is pulled due to the thermal shrinkage stress and the crack occurs.
Cracking Strip: Metal fins are cast on the surface of the casting to prevent cracking.
Creep: The flow or plastic deformation of a metal that is maintained for a long time under a stress lower than the normal yield strength. This effect is particularly important when the stress temperature is close to the recrystallization temperature of the metal.
Creep Limit: The maximum stress that causes the creep rate to be lower than the specified rate.
Critical Cooling Rate: The minimum rate of continuous cooling is just enough to prevent undesired switching.
Cross Section: An internal view of an object cut in half, and the cut surface shows the cross section of the object.
Crucible: A ceramic pot or container, made of graphite or silicon carbide and other materials, with high thermal conductivity, combined with clay or carbon, used to melt metal. Sometimes suitable for pots made of cast iron, steel or forged steel.
Crucible Furnace: A furnace made of coke, oil, gas, or electricity in which metal is melted in a refractory crucible.
Crush: Displacement of sand at the mold joints.
Crystal: A physically uniform solid in which atoms, ions, or molecules are arranged in a three-dimensional repeating pattern.
Crystal Lattice: The arrangement of atoms in a crystal. In space, there are only 14 different lattices.
Crystalline Fracture: The fracture of brittle metals shows a certain crystal plane on the fracture surface.
Cupola: A cylindrical, straight vertical furnace (usually lined with refractory material) that melts metal in direct contact with coke by passing air under pressure through an opening near the bottom of the furnace.
Cure: To harden.
Curing Time (No Bake): The period of time before the sand body reaches its maximum hardness.
Cutoff Machine, Abrasive: A device that uses a thin grinding wheel rotating at high speed to cut off gates and risers from castings, or in similar operations.
Decarburization: The carbon is heated in the medium, the medium reacts with the carbon, and the carbon on the surface of the iron alloy is lost.
Deep Etching: Macroscopic corrosion; In the etching inspection under low magnification (less than 10X), the corrosion degree of the metal in the reagent is far greater than the normal degree of microscopic inspection. General characteristics can be developed; For example, abnormal grain size, segregation, cracks or grain flow.
Defect: The severity of the discontinuity of the product is determined to be unacceptable according to the applicable product specifications.
Deformation Test: The AGS test uses an instrument, such as Dieter Universal Sand Strength Tester (with deformation attachment), to determine the number of inches that a sand sample is compressed before it ruptures.
Degasser: A material that removes gas from molten metals and alloys.
Degassing Flux: A flux for removing gas from the melt.
Dendrite: A crystal of branched appearance, formed during solidification of alloys, a habit of branching controlled by a specific crystal orientation.
Density: The mass per unit volume of a substance, often referred in grams per cubic centimeter or pounds per cubic foot.
Deoxidation: The removal of excess oxygen from molten metal is usually done by adding substances that have a high affinity for oxygen. The oxides of these substances are either gaseous or easily form slag.
Dephosphorization: Phosphorus removal from molten steel.
Descale: Remove the fire scale from the casting surface.
Desulfurization: The sulfur is removed from the molten metal by adding appropriate compounds.
The process of melting consumable wax molds from investment molds by heating, usually at temperatures below 250°F (121°C).
Diameters: In microscopy, an indication of magnification. 1000 diameter equals 1000 times the original size.
Die: The metal block used to form the material by casting, molding, stamping, threading or extrusion.
Die Assembly: The part of the die or die used to fix the die and position it on the punch.
Die Casting (Brit. Pressure Die Casting): A fast water-cooled permanent casting process for non-ferrous metals.
Differential Heat Treatment: A heating process through which the temperature inside the object changes, so that after cooling, different parts can have different properties as required.
Diffuser: X-ray equipment, part of the condensation and focusing system, allows the energy to be evenly distributed.
Dimensional Tolerance Grades: A classification system of tolerance tightness, the purpose is to accurately define the tolerances involved, and to simplify the communication process between the customer and the manufacturer about what is needed and what is possible.
Dip Coat: In solid and shell investment casting, a fine ceramic coating is applied as a slurry to the mold to produce the greatest surface finish, and then a cheaper traditional investment is made.
Direct Casting: Pour the mold from the ladle without using the tundish.
Direct-Arc Furnace: An electric arc furnace in which the molten metal is one of the poles.
Dirt: Indefinite term for any foreign material entering the mold cavity, usually forming defects on the casting surface.
Dirt Trap: Well employed in pouring systems to capture the first poured metal, which may contain dirt or unwanted particles (invalid).
Dispersed Shrinkage: Small shrinkage holes are scattered throughout the casting, which is not necessarily the reason for the scrap.
Disruptive Strength: The maximum strength when a metal is subjected to three principal tensile stresses at right angles to each other and of equal magnitude.
Dissolved Carbon: Carbon is dissolved in steel in liquid or solid form.
Double Annealing: For hypoeutectoid steel, it refers to the process of heating to above the upper critical point (AC3) and keeping it at this temperature until the carbides are completely dissolved, then rapidly cooling, immediately reheating to above A3 and slowly cooling.
Double Tempering: A retempering operation sometimes necessary for steel containing retained austenite which breaks down during cooling from the first tempering to form a new, and hence, untempered martensite.
Dowel: A pin used for parting or die parting surfaces to ensure proper scaling.
Draft: Gradual thinning on the vertical sides of the sample or core box so that the sample or sand pattern is removed without distorting or tearing the sand.
Drag: A mold or pattern lower or bottom section.
Draw: A term used for removing pattern from mold.
A substance, such as alcoholic ammonium nitrate, sodium perborate, and manganese oleate, added to the core or mold mixture to remove or reduce water.
Dry Sand Casting: The process of drying the sand mold at a temperature higher than 212°F (100°C) before use.
Dry Sand Mold: A mold that removes moisture by heating.
Dry Strength, or Dry Bond Strength: The maximum compressive, shear, tensile, or transverse strength of a sand-gravel mixture dried at 220 to 230°F (105 to 110°C) and cooled to room temperature.
Dual Metal Centrifugal Casting: Centrifugal casting is made by pouring another metal into a rotating mold after casting the first metal.
Dye Penetrant: Penetrant is used for crack detection and it has a dye added to make it easier to detect under normal or black light condition. Under normal lighting, the dye is usually red and non-fluorescent. Under black light, the dye is fluorescent and yellow-green in color.
Ejector pins: Removable pins on the mold to help remove the pattern from the mold.
Elastic Limit: The maximum stress that a material can withstand without permanent deformation.
Elasticity: After the deformation force is eliminated, the characteristics of the original shape and size recover original.
Electrode: Compressed graphite or carbon cylinders or rods used in electric arc furnaces, arc lamps, carbon arc welding, etc.
Elongation: The permanent elongation near the interruption of the tensile test; usually expressed as a percentage of the original gauge length.
Engineering Strain (e): The average linear strain is obtained by dividing the elongation of the specimen length by the original strain gauge length.
Engineering Stress (s): Divide the load by the original area.
Equilibrium: The dynamic state of balance between atomic motions. In this state, the result is zero, and this state seems to be static rather than changing.
Exothermic: Formed by or characterized by a thermal reaction, as in oxidation.
Expansion, Sand: When the temperature increases, the size of the sand increases.
Facing Sand: A specially formulated sand mixture is used for the adjacent patterns of the mold to produce a smooth casting surface.
Fatigue: Compared with a single load, the material’s bearing capacity is lost under repeated loads.
Fatigue Crack or Failure: Fracture starting from a core with abnormal cyclic stress concentration. The fracture surface is smooth and often shows concentric (sea shell) marks centered on the nucleus.
Fatigue Limit (Endurance Limit): The maximum stress that a material can withstand in an unlimited number of load cycles.
Feeder: Sometimes referred to as a “riser,” it is part of the gating system that forms the reservoir of molten metal necessary to compensate for losses due to shrinkage as the metal solidifies.
Feeding: The process of supplying molten metal to compensate for volume shrinkage during the solidification of the casting.
Ferritic Steels: Steel with ferrite as the main phase. These steels are magnetic.
Fillet: Recessed corner pieces used for casting patterns, with radius joints instead of sharp inner corners.
Filter: In the pouring part of the casting, unwanted gases are filtered out from the casting.
Fin: A thin metal projection on a casting due to imperfections in the mold or core joint.
Finish Allowance: The margin left for machining on the surface of the casting.
Finish mark: The symbols (f, fl, f2, etc.) appearing on the drawing line indicate the edges of the casting surface to be machined or otherwise finished.
Finish Welding: Welding carried out to ensure the agreed casting quality.
Flash: In castings, metal flakes formed at the mold, core or die joint or parting due to the incomplete matching of the blank holder and the drag, or the mismatch between the blank holder and the blank holder.
Flask: Sand mold is used to make or fix the metal frame of the sand mold. The upper part is cope and the lower part is drag.
Fluidity: The ability of molten metal to flow. Commonly used fluidity measuring devices are: spiral casting and Chinese puzzles.
Fluidize: To make powder or sand (such as fluidized bed) have fluid properties.
Flux: Any substance used to promote fusion. It also means any substance that reduces, oxidizes, or breaks down impurities so that they are carried away as slag or gas.
Foundry Ladle: A container that holds molten metal and transports it from the cupola to the mold.
Foundry Returns: Metals with gates, gates, runners, risers and discarded castings with known chemical composition are returned to the furnace to be remelted. Sometimes called “revert”.
Frictional Wear: The metal particles are displaced or separated from the surface due to contacting with another moving part.
Gas porosity: A state that exists in a casting due to the retention of gases in the molten metal or crystallizer gases generated during the casting pouring process.
Green Sand: A naturally bonded sand, or a mixed molding sand mixture, used for tempering with water when wet or humid.
Grinding: Remove sprue stubs, fins and other protrusions from the casting with a grinding wheel.
Hardenability: In ferrous alloys, it is the property that determines the depth and distribution of hardness after quenching.
Hot Tear: Cracks or fractures formed before the solidification of the metal is complete due to hindered shrinkage. Hot tearing often occurs on the surface of castings, which is usually related to design constraints.
Horizontal Axis Casting Machine : A centrifugal casting machine in which the rotation axis of the mold is horizontal.
Hollow Drill Test (Trepanning): Take a cylindrical sample from the metal slice or structure to determine the integrity of the slice.
High-Alloy Steel: Ferrous alloy containing more than 12% by weight of non-carbon additives.
Heat Treatment: A combination of heating and cooling, which is performed on the metal or alloy to produce the required properties and microstructure.
Heat: The total amount of metal that can be represented by an analytical sample and a set of mechanical tests.
Hardness: Indentation resistance of materials measured by methods such as Brinell, Rockwell and Vickers. The term hardness also refers to the stiffiness of a material, or its ability to resist scratches, abrasion, or cutting.
Hard Sand Match (Match Plate): A sand body which is shaped to conform to the parting line at the beginning of the mold making process. The sand is hardened with linseed oil, mineral sand, silicate cement, etc.
Hotbox process: The resin-based process uses a heated metal core cartridge to produce the core.
ID Grinding: Internal dimension grinding.
Impact Strength: Resistance to impact loads; usually expressed as foot-pounds of energy absorbed by breaking a standard sample.
Impact Value: Under standard conditions, the total energy required to break the standard sample with one blow; for example, Charpy impact test.
Impregnation: The casting is treated with a sealing medium to prevent pressure leakage, such as immersion under pressure with or without prior evacuation, and immersion in hot or cold applications. The media used include sodium silicate, dry oil with or without styrene, plastics and proprietary compounds.
An element that is unintentionally allowed to be added to a metal or alloy.
Some impurities have little impact on performance; others will seriously damage the alloy.
Inclusions: Non-metallic materials in a metal matrix. Sources include reoxidation, refractory materials, slag and deoxidation products.
Indentation Hardness: The resistance of the material to indentation. It is the common hardness test, in which a pointed or rounded indenter is processed into a surface under a substantially static load.
Indirect-Arc Furnace: An alternating current (alternating current) electric arc furnace in which the metal is not in one of the poles.
Induction Furnace: An AC melting furnace using electric induction heat.
Induction Hardening: A surface hardening process that includes heating locally using a pulsating magnetic current to reach the austenite transformation temperature Ac3 and then quenching.
Induction Heating: The heating process of resistance and hysteresis loss caused by metal being placed in a changing magnetic field around a coil with alternating current.
Inert Gas: A gas that cannot support combustion or sustain any chemical reaction; for example, argon or helium.
Ingot: An ingot is a piece of relatively pure material, usually metal, that is cast into a shape suitable for further processing.
Insert: A part usually made of metal that can become an integral part of the casting when placed in a mold.
Insulating Pads and Sleeves: Relative to low temperature, insulating materials, such as gypsum, diatomaceous earth, etc., are used to reduce the curing rate. As the sleeves on the open risers, they are used to maintain the metal liquid, thereby improving the feeding efficiency.
Intergranular Corrosion: Corrosion in metals preferentially occurs along grain boundaries.
Internal Shrinkage: The voids or void network in the casting are caused by insufficient feed of this part during the solidification process.
Internal Stresses (or Thermal Stresses): It is usually the stress generated during the cooling of the part.
Interrupted Quench: The casting is removed from the quenching tank before it reaches the temperature of the quenching tank.
Investment Casting: Castings produced in a mold obtained by casting a shell on a consumable mold with refractory materials. The consumable template can be composed of wax, plastic, or other materials, which are removed before filling the mold with liquid metal.
Iron: Irons not falling into the steel categories, as Gray Iron, Ductile Iron, Malleable Iron, White Iron, Ingot, and Wrought Iron.
Iron, Malleable: A mixture of carbide iron and carbon, including a small amount of silicon, manganese, phosphorus and sulfur, after casting (white iron, a combination of carbides) is transformed into a structure containing tempered carbon (graphite) nodules by heat treatment Ferrite matrix.
ISO: International Standards Organization.
Isocure: The proprietary name of the adhesive system developed for the Ashland (cold box) process. It is a proprietary process in itself.
Isothermal: Used to modify or explain changes or other phenomena that occur at a constant temperature.
Joint Welding: Production welding is used to weld castings together to obtain a whole.
NBS: National Bureau of Standards. Changed to NIST in 1988.
Necking: The cross-sectional area of the metal is reduced by stretching.
Needles: The slender needle-like crystals gradually become thinner at both ends, such as martensite.
Negative Quenching (Negative Hardening): The cooling is accelerated in water or oil when the temperature is below the critical range.
NFFS: Non-Ferrous Founder’s Society.
Nimonic: A nickel-based casting alloy that is resistant to stress and high temperature oxidation.
NISA: National Industrial Sand Association.
NIST: National Institute of Standards and Technology.
Nital: A solution of nitric acid in alcohol is used as an etchant in iron metallography.
Nitriding: A surface hardening process that involves heating in ammonia gas or contacting with nitrogen-containing materials to promote nitrogen absorption.
Nitrogen Flush: The nitrogen is passed through the metal melt (such as valve bronze) under vacuum to improve the tensile properties and pressure tightness.
Nobake Binder: A synthetic liquid resin sand binder that is completely hardened at room temperature and generally does not require baking. It is used in the cold-setting process.
Nodular Iron: A type of iron usually gray cast iron, properly treated with a nodularizing agent, so that all or most of the graphitic carbon is in the form of nodular or nodular graphite during casting. It is usually called ductile iron.
Nondestructive Testing (Inspection): Testing or inspection that does not destroy the object being tested or inspected.
Nonferrous: It refers to alloy in which the predominate metal or solvent is not iron.
Normal Segregation: The concentration of alloy components with a low melting point solidifies in those parts of the casting.
Normalizing: The iron alloy is heated to an appropriate temperature higher than the transformation temperature Ac3, and then cooled at an appropriate speed, usually in still air to a temperature much lower than the transformation range.
Nucleation: In the absence of external interference, solid crystals start from the liquid phase, or solid crystals start from the liquid phase, or new phases in the solid rarely occur.
Open Grain Structure: Coarse crystals and porous defects appear in the castings during processing or fracture.
Open Riser: A riser whose top is open to the atmosphere through the top of the mold.
Optimum Moisture: The moisture content that results in the maximum nature of the sand-gravel mixture.
Orange Peel: A pebble-like surface formed during the mechanical forming of coarse-grained metal plates.
Oven, Drying: A furnace or oven used for drying molds or cores.
Overaging: Aging of precipitation hardening alloys under conditions greater than the time and temperature required to obtain maximum strength or hardness.
A term that refers to the undesirable coarse-grained structure of metal after exposure to excessively high temperature, but it is not necessarily permanently damaged.
Unlike the combustion structure, the structure produced by overheating can be corrected by proper heat treatment, machining, or a combination of the two.’
Overstressing: The metal is permanently deformed by applying stress that exceeds the elastic limit.
Oxidation: Any reaction of an element with oxygen. In a narrow sense, oxidation refers to the process in which an element or compound absorbs oxygen. According to the theory of electrons, it is a process in which an element loses electrons.
Oxide: A compound of oxygen with another element.
Oxidizing Atmosphere: The combustion of fuels in an atmosphere where excess oxygen exists leads to the atmosphere. In this process, there is no unburned fuel lost.
Padding: The process of adding metal to the cross section of the cast wall. It is usually extended from the riser to ensure that there is enough feed to the local area. If there is no added metal, it will shrink.
Parted Pattern: A pattern made in two or more parts.
Parting: Seams, split lines, are separated in this mold to allow removal of the pattern.
Parting Line: The line on the template or casting corresponds to the separation between the barrel and the drag part of the sand mold.
Passivity: Passivate the property of certain metals to become abnormally inactive to certain reagents.
Pattern: A form of wood, plastic, metal, or other materials. A mold material is placed around it to make a mold.
Pattern Draft: The taper of the vertical elements in the pattern which makes it easy to separate the pattern from the compacted sand mixture.
A full-scale drawing showing the pattern arrangement and structural features.
A craftsman who uses wood, plastic, or metals (such as aluminum, brass, etc.) to make casting patterns.
The blasting action produced by the impact of metal projectiles is often used to put the surface in compression to improve fatigue performance.It also has the small end of a castwork hammer.
Perlite: A kind of high siliceous volcanic rock that can be expanded into porous particle clusters by heating. Perlite can be used as an insulating material for foundry sand mixtures. Not to be confused with pearlite.
Permanent Mold: The metal mold is composed of two or more parts; not an ingot mold. It is repeatedly used to produce many castings of the same form.
Permeability: Characteristics of the mold material that allows the passage of gas. The property of the sand mold that allows gas to pass through.
Phase Diagram: Graphical representation of the equilibrium temperature and composition limits of the phase field reaction in an alloy system. In a binary star system, the temperature is usually the ordinate, and the component is usually the abscissa. Ternary and more complex systems require several two-dimensional graphs to fully show the temperature-composition variables. In alloy systems, pressure is usually considered constant, although it may be treated as an additional variable.
Photomicrograph: The photo of the metal particle structure observed when the optical magnification is over 10 times. The term photomicrography can be used.
Physical Metallurgy: The science of studying the physical and mechanical properties of metals and alloys.
Pitting: A form of wear characterized by the existence of cavities on the surface, the formation of which is attributed to processes such as fatigue, local adhesion, cavitation or corrosion.
Plane Strain: A state of stress in linear elastic fracture mechanics, that is, the strain in the direction perpendicular to the axis of applied tensile stress and the direction of crack propagation is zero. Under plane strain conditions, the fracture failure surface is perpendicular to the main tensile stress axis.
Plastic Deformation: The permanent deformation of a material under applied pressure.
Porosity: The casting appears unsound with pores and shrinkage.
Postheating: A process used immediately after welding to temper or provide a controlled cooling rate by applying heat to the welded area to avoid the formation of hard or brittle structures.
Pouring: Transfer the molten metal from the furnace to the ladle, from the ladle to the ladle, or from the ladle to the mold.
Pouring Cup: The bell mouth part at the top of the lower gate. It can be manually formed in the groove, or it can be used to form a molded part of in the lower gate; the baking cup can also be placed on the top of the cylinder, above the lower gate.
Precipitation Hardening: The hardening process of an alloy in which components are precipitated from a supersaturated solid solution.
Precipitation Heat Treatment: Various aging treatments that carried out at high temperatures to improve certain mechanical properties by separating out from the solid solution.
Preheating: The general term for heating materials, such as the mold in die casting, as a preparation for operation to reduce thermal shock and prevent adhesion of molten metal.
Primary Choke: The part of the gating system that can most restrict or regulate the flow of metal into the cavity.
Process Capability: The amount of change in the output of a controlled manufacturing process is a range defined by plus or minus three standard deviations.
Proeutectoid: A component separated from a solid solution before the eutectoid is formed.
Profile Tolerance: Aiming at the problem of positioning and tolerance control of rough parts in machine tool fixtures, a positioning and tolerance control system was developed. Starting from the positioning points on the casting, a “perfect profile” of all surfaces and features is established. The tolerance envelope around this profile defines the limits of acceptable parts.
PSI: Pounds per square inch.
Purging: Remove air and other undesirable gases from the furnace or heating box.