Foundry process term

Time：2022-03-27 19:38:42 Source：未知 Click：second

Alloy	A metal made by combining two or more metallic elements. The addition of certain chemical elements impart properties into the base metal such as greater tensile strength.
Annealing	Annealing is a heat treatment process that changes the physical properties of a material to and sometimes also the chemical properties to increase ductility and reduce the hardness to make it more workable. involving heating and slow cooling in a controlled manner in order to alter mechanical or physical properties, particularly hardness softening and stress relief.
Blasting	Cleaning a metal object by striking it with high velocity media, some common media used in the blast process are sand or hard metal shot.
Brinell Hardness	Test used to determine the hardness of metals. The test is conducted by applying a known load to a steel ball of known diameter to the surface of the metal that's being tested. The diameter of the resulting impression that's made on the test piece is measured. This measurement is cross referenced to obtain the Brinell hardness value.
Burned on sand	A defect caused by metal penetration into mold or core sand. This results in a mixture of sand and metal on the surface of the casting.
Cast Iron	A series of ferrous alloys that contain over 1.74% carbon.
Case hardening:	Process for hardening ferrous alloys so that surface layers are made substantially harder than interior or core materials.
Casting drawing:	Engineering drawing that shows the final shape of a part to be cast. It includes all information related to dimensions, tolerances, machining and any other data necessary to determine foundry procedures.
Chaplet	Metal support or spacer used in molds to help hold cores in proper position.
Chemical analysis	The measurement and reporting of the different elements and also their concentration by percentage, that are found within a material sample.
Chill	A metal insert that's placed in a sand mold, it's used to produce local chilling and equalize the rate of solidification in the casting.
Cope	Top half of a pattern, flask, mold or core.
Core	A molded sand insert that is used to form the interior of a casting and occasionally external features Insert used to create mold cavities and openings that cannot be formed using a pattern on its own. Cores are often formed from molding sand to ensure adequate strength, hardenability and removability during shakeout. Cores will increase the cost of a casting and should be used only when necessary.
Core Box	Enclosed mold in which sand can be packed to form a core. Box made of wood metal or plastic, the cavity of which forms the external shape of the core
Core wash	A liquid solution that's applied to cores then dried. The refractory material in the solution is used to prevent metal penetration into the core sand.
Coreprint	A projection on a pattern that leaves an impression in the mold for supporting the core.
Crush	The deformation of a mold through the displacement of sand at mold joints
Cure	To harden.
Draft	The taper on the vertical sides of a pattern or corebox that permits the core or sand mold to be removed without distorting or tearing the sand. Taper applied to a pattern’s vertical surfaces. The taper facilitates clean and easy removal of a pattern from a mold. Minimum section thicknesses should be maintained when including drafts in pattern designs.
Drag	Lower or bottom section of a mold, pattern or flask. In many molding systems the cope is rotated until it is downward facing and the "drag mold" is dragged underneath it for closing the two halves of the mold. Bottom half of a pattern, flask, mold or core.
Degassing:	Process for removing unwanted gasses from casting materials, typically by pumping a neutral gas through molten metal. Unwanted gases form in metal castings through mechanical entrapment or by chemical reactions within liquid metal. If not removed, unwanted gases can create porosity in metals, which can compromise strength and integrity.
Ductile Iron	Iron in which the carbon is in the form of spherical nodules. This form of iron has a greater ductility and toughness and is less likely to promulgate cracks than other cast irons. Ductile iron has a good machinability, excellent impact properties, and a high modulus of elasticity.
Feeder	Often times referred to as a riser, it is part of the gating system that supplies the reservoir of molten metal that's necessary to compensate for the losses due to shrinkage as the metal solidifies.
Finish Allowance	The amount of stock left on the surface of a casting for machining, typically between 3 and 4 mm.
Flashing:	Excess material formed on an object during the casting process, typically resulting from gaps formed within a parting line.
Flask	A metal box that's used to hold the mold sand while the sand is being pressed against the pattern, usually consists of a top and bottom, "cope and drag". Container, comprised of two halves, a cope and drag, used to form sand molds. A pattern is placed inside the flask, typically fastened to a match plate, and packed with sand. The cope and drag are separated, the pattern is removed and the two parts are reassembled to form the mold cavity.
Gas porosity	Small voids in a casting that are formed by gas that was trapped when the molten metal was poured into the mold. The intial source of the gas varies. When encountered this defect will usually appear as a smooth spherical void.
Gate	The portion of a gating system where the molten metal enters the mold cavity. Channel that carries molten metal between mold cavities that would be otherwise separated. Gates are formed into a mold extraneous of the desired final product and must be removed by machining once a casting has cooled.
Gating System	The complete assembly of sprues, runners and gates in the mold, all of which supply the mold with molten metal Network of connected channels that carries molten metal into the mold cavity. Excess material solidified in the gating system, called gates, must be removed by machining once casting has cooled.
Gray Iron	Cast iron whose graphite is contained in flakes spread throughout its matrix. Gray iron has excellent castability and good machinability.
Green sand	Moist clay-bonded sand that is used for molding.
Green sand casting	Type of sand casting characterized by the use of a wet sand mixture to create a mold. Dry sand molds are limited in the amount of weight they can support; green sand molds can support a much higher mass. In addition to water, bentonite, clay, and anthracite are normal components of green sand mixtures.
Guide Pin	An alignment pin that projects from a flask and is contained by a bushing on the opposite flask. This insures that the cope and drag molds are properly aligned.
Heat	A single furnace charge of metal.
Heat Treatment	A controlled process of heating and cooling operations that are applied to a casting that's in a solid state. This process is used to alter the casting in a way that produces the desired mechanical properties. Various heat treating processes are used to attain different objectives. Annealing is generally used for softening and stress relieving while most other processes are used to harden the casting either locally or all the way through.
Inclusions	Slag particles, refractory materials, sand or deoxidation prdoucts trapped in the casting during the solidification process.
Inoculent	Materials that are added to the molten metal to modify the structure, and thereby alter the physical and mechanical properties.
Loose pattern:	Pattern free from any mounting plate, which results in castings with minimal gates and risers. Loose, or unmounted, patterns are rarely used by foundries, except for prototypes and very large castings.
Ladle	Metal vessel lined with refractory material that is used to transport or pour molten metal.
Machining:	Process of mechanically removing excess material by cutting, drilling, grinding or sanding. Many sand-casted products require machining to achieve smooth surfaces free from any gates and risers.
Machining allowance	Amount of additional material intentionally cast to provide excess stock for machining.
Mechanical Properties	Physical properties which describe the behavior of a metal when it's subjected to types of mechanical usage. Some examples of mechanical properties are tensile strength, elongation, and hardness.
Mold	The complete sand container formed by the union of the cope and drag halves. This "sand box" contains the internal cavity which will become the casting once poured. Also inside the mold are the various risers, runners, chills, filters, cores, and ingate. Structure into which molten metal is poured to form a casting. Molds can be reusable (as in die casting) or disposable (as in sand and investment casting).
Mold Cavity	The impression in a mold produced by the removal of the pattern. This cavity is filled with molten metal to form the casting.
Mold wash	Solution that is used to coat the cavity walls, helps prevent metal penetration into the mold sand.
Mounted pattern:	Pattern fastened to a board or match plate, which can then be fixed into a flask. Mounted patterns allow for quicker and better-quality mold making, while also allowing groups, or sets, of parts to be formed in a single mold.
Minimum section thickness:	Minimum thickness a section can be cast, based on material fluidity, desired quality and the area and complexity of a casting’s surface.
Mulling	The mixing of sand, water, and binding agents in preparation for use in molding or coremaking
Parting Line	The line showing the separation of the two halves of the mold. Seam formed between cope and drag portions of a mold, where additional material may accumulate and show as a raised line, called flashing, on a casting. Machining can be used to minimize or remove the appearance of a parting line.
Pattern	The wood, metal, or plastic shape used to form the cavity in the sand. A pattern may conisist of one or more impressions and is normally mounted to a board or plate along with a runner system. Object made in the shape of the object to be cast. Patterns are used to form the mold cavities into which molten metal will be poured. They can be made into a single piece or split patterns comprising upper and lower sections.
Physical properties	The distinguishing characteristics or qualities used to describe a metal, i.e. Tensile Strength, Yield Strength, Elongation.
Precipitation hardening	Form of heat treatment involving precipitation from a solid solution, used to improve certain mechanical properties.
Pig Iron	Blocks of iron with known chemical makeup that are used for melting for the production of ferrous castings.
Pour cup	The pattern piece where the molten iron enters the mold.
Quenching:	Hardening method achieved through rapid cooling, typically by immersing in water, oil or other solution.
Returns	Metal in the form of gates, sprues, risers, or defective castings which are put back into the furnace for melting.
Riser	A reservoir of molten metal used to supply a contracting, cooling casting with additional material, risers are used to pervent internal or external voids caused by shrinkage. Also referred to as a feeder. Reservoir cavity included in the design of a mold to counteract the effects of material shrinkage during cooling. As casting materials shrink they draw additional material from risers to prevent cavity formation. Risers should cool and solidify with the slowest components of a casting—usually the thickest and largest part—and should contain enough material to compensate shrinkage.
Runner	Part of the gating system which carries molten metal from the sprue to the gates.
Sand inclusion	Cavities or surface imperfections on a casting caused by sand washing into the mold cavity.
Seacoal	Finely ground coal which is mixed with mold sand.
Shakeout	The process of separating the solidified casting from the mold material.
Shell cores	Cores that have a shell-like structure, made from a mixture of sand and a heat activated resin that serves as a binder. The boxes that produce these cores are heated.
Shrinkage	Contraction of metal in the mold during the solidification (cooling). This term also applies to a type of casting defect. The defect is a void or voids of various geometries that are formed by the insufficient flow of feed metal into the casting during solidification. Amount of contraction that occurs when casting materials harden and cool to room temperature. Pattern and mold design should account for shrinkage according to properties of the casting material.
Slag	Nonmetallic impurities that float to the top of the molten iron during melting and pouring.
Soundness:	Measure of impurities and/or discontinuities such as sand inclusions, slag inclusions, macro porosity (pores greater than 50 nm in diameter) and shrinkage.
Sprue	The channel through which the molten metal enters into the gating system for distribution to the risers and gates. Also referred to as downsprue. Passage through which molten metal is poured to fill the mold cavity. A sprue also refers to the excess material solidified in the passageway that must be removed once cooled.
Test bar	Bar poured for determining the mechanical properties of the heat lot. These properties are assessed by way of destructive testing.
Tempering:	Form of heat treatment, where hardened steel is reheated to a temperature below the critical range to soften it and improve impact strength.
Tolerance:	Permissible range of variation, given in nominal dimensions, for a finished product. Accepted tolerances are typically agreed upon by both supplier and customer, and should be indicated in casting drawings.
Vent	An opening or passage in a mold or core that allow gases to escape when the mold is poured.