1、Designation: A644 09aA644 13Standard Terminology Relating toIron Castings1This standard is issued under the fixed designation A644; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses
2、indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.ausferrite, na cast iron matrix microstructure, produced by a controlled thermal process
3、, which consists of predominantlyacicular ferrite and high carbon austenite. (See austempered ductile iron.)austempered ductile iron, na ductile cast iron that has been produced by a controlled thermal process which results in a matrixmicrostructure consisting of predominately acicular ferrite and h
4、igh carbon austenite.austenitize, vtto convert the matrix of a ferrous alloy to austenite by heating above the transformation temperature.batch, nthe component raw materials properly weighed, proportioned, and mixed for delivery to a processing unit. Also, theproduct output from a processing unit in
5、 which there is essentially no product output until all component materials are chargedand processed.brittle fracture, nfracture that occurs without appreciable plastic deformation of the material.brittle fracture area, nThe fraction or percent of the fracture surface that formed by brittle fracture
6、. (When observed with noor low magnification, brittle fracture appears whiter and shinier than ductile fracture.)capability index (Cp),nfor a stable process, the specification range divided by six times the standard deviation.Cp 5USL2 LSL!63scapability index (Cpk),nfor a stable process, the smaller
7、of the upper capability index (CPU) or the lower capability index (CPL).carbide, primary, ncarbide precipitated in cast iron during solidification.cast iron, na generic term for a series of alloys primarily of iron, carbon, and silicon in which the carbon is in excess of theamount which can be retai
8、ned in solid solution in austenite at the eutectic temperature.cementite, na very hard and brittle compound of iron and carbon corresponding to the empirical formula Fe3C, commonlyknown as iron carbide.cementite, primary, ncementite precipitated in cast iron during solidification.Also known as prima
9、ry carbide. (See cementite.)certification, nA document supplied by the maker or manufacturer of a product which testifies to the factuality or truth ofstatements made that the requirements of a product standard have been met.chill, nan object, usually metal, imbedded in a portion of the mold to acce
10、lerate the local rate of heat removal from the metalbeing cast.chill, vto accelerate the freezing rate of cast iron, usually in a localized region, to refine the graphite structure or cause formationof primary carbides.chill, microstructural, na localized region of primary carbides in a casting made
11、 from a cast iron that would normally solidifyfree of primary carbides.chilled iron, na cast iron that would normally solidify free of primary carbide which is purposely caused to solidify as whitecast iron, locally or entirely, by accelerated cooling.1 This terminology is under the jurisdiction of
12、ASTM Committee A04 on Iron Castings and is the direct responsibility of Subcommittee A04.91 on Editorial Matters andNomenclature.Current edition approved July 1, 2009May 1, 2013. Published July 2009May 2013. Originally approved in 1971. Last previous edition approved in 2009 asA644 - 09.A644 - 09a.
13、DOI: 10.1520/A0644-09A.10.1520/A0644-13.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM
14、 recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1compacte
15、d graphite iron, na cast iron that has been treated in the liquid state so as to cause its graphitic carbon to occur inthe compacted graphite shape in the as-cast condition. (See graphite, compacted and graphite, spheroidal.)compound, nan intimate mixture of all the ingredients necessary for a finis
16、hed material or pression gasket, na gasket designed to be used under pression seal, na seal that is attained by a compressive force on the sealing material.confidence level, nthe probability, or expected percent of the times, that the selected percent (P %) of the actual population lieswithin the to
17、lerance interval calculated from the data sample.direct reduced iron, niron ores that have been reduced to essentially metallic iron by heat and reducing agents, but withoutmelting, and processed into suitable shapes (typically pellets) for use as a charge material in a melting operation.dual metal,
18、 ntwo metals of different composition that are fusion bonded at all interfacial surfaces by casting metal of onecomposition against metal of a second composition.ductile fracture, nfracture that occurs with appreciable plastic deformation of the material.ductile fracture area, nThe fraction or perce
19、nt of the fracture surface that formed by ductile fracture. (When observed with noor low magnification, ductile fracture appears grayer and duller than brittle fracture.)ductile iron, na cast iron that has been treated in the liquid state so as to cause substantially all of its graphitic carbon to o
20、ccuras spheroids or nodules in the as-cast condition.durometer(1) an instrument for measuring the hardness of rubber-like materials. (2) a term used to identify the relative hardnessof rubber-like materials, for example: “low durometer” (relatively soft) or “high durometer” (relatively hard).elastom
21、er, na macromolecular material that returns rapidly to approximately its original dimensions and shape after substantialdeformation by a weak force and release of the force.DISCUSSION(a) Elastomers are divided into two major polymer systems: thermoset and thermoplastic. (b) In standards for rubber,
22、the word elastomer is not to beused interchangeably for the term “rubber”.elastomeric, adjhaving the characteristics of an elastomer.elongation, nextension produced by a tensile stress.ferritize, vtto increase the quantity of ferrite in the matrix of a ferrous casting through an appropriate heat tre
23、atment.ferritizing anneal, nthe process of producing a predominantly ferritic matrix in cast iron through an appropriate heat treatment.gasket, nany preformed, deformable device designed to be placed between two adjoining parts to provide a seal.graphite, compacted, na graphite shape that is interme
24、diate between flake graphite and nodular graphite that typically appearsin a polished section as thick flakes with blunt (compacted) ends.graphite flake, nan irregularly shaped particle of graphite, usually appearing in a polished section as curved plates, such as foundin gray cast irons.graphite, n
25、odular, nspheroidal shaped graphite typically found in ductile irons and compact clusters of graphite typically foundin malleable irons. (See graphite, spheroidal , and temper carbon.)graphite, primary, ngraphite precipitated in cast iron during solidification.graphite rosette, narrangement of graph
26、ite flakes in which the flakes extend radially from centers of crystallization in gray castiron.graphite, spheroidal, nspheroidal shaped graphite having a polycrystalline radial structure, usually found in ductile iron and toa controlled, limited extent in compacted graphite iron.graphitize, vtto pr
27、ecipitate graphite in an iron-carbon alloy.gray iron, ncast iron that has a relatively large proportion of the graphitic carbon present in the form of flake graphite. The metalhas a gray fracture.hardness, nthe resistance to indentation as measured under specified conditions.A644 132heat, nthe total
28、 molten metal output from a single heating in a batch melting process or the total molten metal output fromessentially a single heating in a continuous melting operation using basically constant charge and processing conditions andtargeted at a fixed metal chemistry at the furnace spout.Aheat can al
29、so be defined as a fixed time period for a continuous meltingoperation provided that it is shorter than the time period covered by the above definition.hydrostatic pressure, na state of stress in which all the principal stresses are equal (and there is no shear stress), as in a liquidat rest; the pr
30、oduct of the unit weight of the liquid and the difference in elevation between the given point and the free liquidelevation.inoculated iron, ncast iron, either liquid or solid, to which one or more inoculating alloys have been added while the iron wasin the molten state.inoculated iron, fully, ncast
31、 iron, either liquid or solid, to which all molten metal additions, including all inoculating alloys, havebeen added.inoculating alloy, nan alloy added to molten iron for the principle purpose of nucleating a primary phase such as graphite.Inoculating alloys are frequently used to avoid the formatio
32、n of primary carbide by enhancing the nucleation of graphite.lot, na finite quantity of a given product manufactured under production conditions that are considered uniform.lower capability index (CPL), nthe difference between the sample mean (x) and the lower specification limit divided by threetim
33、es the standard deviation.CPL5x 2 LSL!33sCPL5x 2 LSL!33slower specification limit (LSL), n the lowest specified value.M, nthe number of standard deviations, mutually concurred by the supplier and purchaser, to be used for calculations ofstatistical conformance to such items as minimums, maximums, sp
34、ecification ranges, and process capability indices.DISCUSSIONM values of three or less were used in establishing initial ASTM specification limits; higher values of M result in reduced allowable variability foractual values when the property of interest is bounded on both sides; in the case of a min
35、imum or maximum, a high value of M can result in the needfor excessively high or low mean property values (x ).malleable, ferritic, na ferrous alloy that is cast as white iron but which is converted by an appropriate heat treatment to amicrostructure of temper carbon embedded in a ferritic matrix es
36、sentially free of pearlite and carbide.malleable iron, na cast iron of such composition that it solidifies as white iron, which upon proper heat treatment is convertedto a metallic matrix with nodules of temper carbon.malleable, pearlitic, na ferrous alloy that is cast as white iron but which is con
37、verted by an appropriate heat treatment to amicrostructure of temper carbon embedded in a matrix containing a controlled quantity, form, and distribution of pearlite ortempered martensite.malleableize, vtto convert white iron into malleable iron through an appropriate graphitizing heat treatment.man
38、ufacturer, castings, nthe entity that directly controls the melting and pouring of metal, and casting it into a product coveredby the standard.maximum (non-statistical), nthe highest acceptable actual test result; any valid individual test result above the maximum iscause for rejection of the compon
39、ent or material lot being tested.All xi#Maximum5USLmaximum (statistical), nthe highest acceptable statistical test result; for compliance, the sample mean (x) plus M standarddeviations(s), where M is a matter of agreement between the supplier and purchaser, must be less than, or equal to, the uppers
40、pecification limit.x1M 3s#Maximum5USLx1M 3s#Maximum5USLDISCUSSIONA644 1331A normal data distribution is assumed for the population from which the data sample was drawn.DISCUSSION2M values of three or less were used in establishing initial ASTM specifications limits. Higher values of Mresult in reduc
41、ed allowable variabilityfor actual values when the property of interest is bounded on both sides. In the case of a minimum or maximum, a high value of M can result in theneed for excessively high or low mean property values (x).mean (x ),nthe sum of the individual data points (xs) divided by the num
42、ber of data points ( n).x 5(xinx 5(xinmelt, nthe total molten metal produced in a single heat.merchant pig iron, npig iron produced for commercial sale to foundries.minimum (non-statistical), nthe lowest acceptable actual test result; any valid individual test result below the minimum is causefor re
43、jection of the component or material lot being tested.All xi$Minimum5LSLminimum (statistical), nthe lowest acceptable statistical test result; for compliance, the sample mean (x) minus M standarddeviation(s), where M is a matter of agreement between the supplier and purchaser, must be greater than,
44、or equal to, the lowerspecification limit (LSL).x 2M 3s$Minimum5LSLx 2M 3s$Minimum5LSLDISCUSSION1A normal data distribution is assumed for the population from which the data sample was drawn.DISCUSSION2M values of three or less were used in establishing initial ASTM specification limits; higher valu
45、es of M result in reduced allowable variabilityfor actual values when the property of interest is bounded on both sides; in the case of a minimum or maximum, a high value of M can result in theneed for excessively high or low mean property values (x ).mottled iron, na cast iron containing a mixed st
46、ructure of gray iron and white iron of variable proportions. The fracture has amottled appearance.nodular graphite, ngraphite in the form of nodules or spheroids in iron castings.nodularity, nthe volumetric proportion of spheroidal or nodular graphite to total graphite in a ductile iron or a compact
47、edgraphite iron matrix (see Test Method A247, for Evaluating the Microstructure of Graphite in Iron Castings,2 Types I and II).nodularity, degree of, nthe volumetric proportion of spheroidal or nodular graphite to total graphite in a ductile iron matrix (seeTest Method A247, Types I and II).nodulizi
48、ng alloy, nan alloy added to molten iron for the primary purpose of causing the formation of spheroidal graphite duringsolidification.pig iron, nthe high carbon iron product obtained by the reduction of iron ores, typically in a blast furnace or an electric furnace,and cast into uniform shapes (pigs
49、) having physical and chemical characteristics suitable for end use as foundry melting stock.range, data, nthe absolute value of the difference between the highest and lowest values in a set of data.range, specification (non-statistical), nthe absolute value of the difference between the highest (USL) and lowest (LSL)specified values; for compliance with a non-statistical range, each valid individual test result must lie at, or within, thespecification limit
