1、Designation: E209 00 (Reapproved 2010)Standard Practice forCompression Tests of Metallic Materials at ElevatedTemperatures with Conventional or Rapid Heating Ratesand Strain Rates1This standard is issued under the fixed designation E209; the number immediately following the designation indicates the
2、 year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers compression test in which thes
3、pecimen is heated to a constant and uniform temperature andheld at temperature while an axial force is applied at acontrolled rate of strain.NOTE 1In metals with extremely high elastic limit or low modulus ofelasticity it is conceivable that 1.5 percent total strain under load could bereached before
4、 the 0.2 percent-offset yield strength is reached. In thisevent the 0.2 percent-offset yield strength will be the end point of the testunless rupture occurs before that point.NOTE 2For acceptable compression tests it is imperative that thespecimens not buckle before the end point is reached. For thi
5、s reason theequipment and procedures, as discussed in this recommended practice,must be designed to maintain uniform loading and axial alignment.1.2 Preferred conditions of testing are recommended so thatdata from different sources conducting the tests will becomparable.1.3 The values stated in inch
6、-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is th
7、eresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing MachinesE9 Test Methods of Compression
8、Testing of Metallic Ma-terials at Room TemperatureE21 Test Methods for Elevated Temperature Tension Testsof Metallic MaterialsE83 Practice for Verification and Classification of Exten-someter Systems3. Apparatus3.1 Testing MachinesMachines used for compression test-ing shall conform to the requireme
9、nts of Practices E4.3.2 Bearing Blocks and Loading AdaptersLoad both endsof the compression specimens through bearing blocks orthrough pin-type adapters that are part of the compression-testing assembly. Bearing blocks may be designed with flatbearing faces for sheet- or bar-type specimens. Sheet sp
10、eci-mens may also be loaded through pin-type adapters that areclamped rigidly to the grip sections of specimens designed forthese adapters (1).3The main requirement is that the method ofapplying the force be consistent with maintaining axial align-ment and uniform loading on the specimen throughout
11、the test.When bearing blocks with flat faces are used, the load-bearingsurfaces should be smooth and parallel within very close limits.The tolerance for parallelism for these surfaces should be equalto or closer than that specified for the loaded ends of thespecimens. The design of the equipment sho
12、uld provideadequate rigidity so that parallelism is maintained duringheating and loading. The bearing blocks or pin-type adaptersshould be made of a material that is sufficiently hard at thetesting temperature to resist plastic indentation at maximumforce. They should also be of a material or coated
13、 with amaterial that is sufficiently oxidation resistant at the maximumtesting temperature to prevent the formation of an oxidecoating that would cause misalignment. In any compressiontest it is important that the specimen be carefully centered withrespect to the bearing blocks, which in turn should
14、 be centeredwith respect to the testing machine heads.NOTE 3Bearing blocks with straight cylindrical or threaded holesdepending on specimen design may be used for bar-type specimensproviding the apparatus qualifies in accordance with Section 9.NOTE 4Bearing blocks of an adjustable type to provide pa
15、rallelloading surfaces are discussed in Test Methods E9. Bearing blocks with a1This practice is under the jurisdiction ofASTM Committee E28 on MechanicalTesting and is the direct responsibility of Subcommittee E28.04 on Uniaxial Testing.Current edition approved Sept. 1, 2010 Published November 2010.
16、 Originallyapproved in 1963. Last previous edition, approved in 2005 as E20905. DOI:10.1520/E0209-00R10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standard
17、s Document Summary page onthe ASTM website.3Boldface numbers in parentheses refer to references at the end of this practice.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.spherical seat for the upper block are also shown.3.3 Subpres
18、sesA subpress or other alignment device isnecessary in order to maintain suitable alignment when testingspecimens that are not laterally supported, unless the testingmachine has been designed specifically for axial alignment anduniform application of force in elevated-temperature compres-sion testin
19、g. A subpress for room-temperature testing is shownin Test Methods E9. For elevated-temperature compressiontesting, the subpress must accommodate the heating andloading devices and the temperature-sensing elements. Thedesign of the subpress is largely dependent on the size andstrength of the specime
20、ns, the temperatures to be used, theenvironment, and other factors. It must be designed so the ramdoes not jam or tilt the frame as a result of heating orapplication of force. If the bearing faces of the subpress, theopposite faces of both bearing blocks, and the ends of thespecimen are respectively
21、 plane and parallel within very closelimits, it is unnecessary to use adjustable or spherical seats. Inany case, the specimen should be properly centered in thesubpress.3.4 Compression Testing JigsWhen testing sheet material,buckling of the specimen during application of compessiveforces must be pre
22、vented. This may be accomplished by usinga jig containing side-support plates that bear against the facesof the specimen. The jig must afford a suitable combination oflateral-support pressure and spring constant to prevent buck-ling without interfering with axial deformation of the specimen(1). Alth
23、ough suitable combinations vary somewhat withvariations in specimen material and thickness, testing tempera-ture, and accuracy of alignment, acceptable results can beobtained with rather wide ranges of lateral-support pressureand spring constant for any given test conditions. Generally,the higher th
24、e spring constant of the jig, the lower thelateral-support pressure that is required. Proper adjustment ofthese test variables may be established in preliminary verifi-cation tests for the equipment (Section 9).3.4.1 This practice does not intend to designate specificcompression jigs for testing she
25、et metals, but merely to providea few illustrations and references to jigs that have been usedsuccessfully. Many other jigs are acceptable provided theyprevent buckling and pass the qualification tests set forth inSection 9. Satisfactory results have been obtained in room-temperature testing using t
26、he jigs illustrated in Test MethodsE9. These jigs usually require that the specimen be lubricatedto permit normal compression on loading. For elevated-temperature testing, modified jigs that accommodate the heat-ing and strain-measuring equipment as well as the temperature-sensing elements must be u
27、sed. A number of compression-testing jigs have been evaluated specifically for performance inelevated-temperature tests (2, 3). The preferred type dependson the material, its thickness, and the temperatures involved.For moderately elevated temperatures, one of the room-temperature designs may be use
28、d in an oven in which the air iscirculated to provide uniform heating. One design for side-support plates that has been found satisfactory for use attemperatures up to 1000F (538C) when lubricated withgraphite is shown in Fig. 1( a) (4). Longitudinal grooves are cutin each plate with the grooves off
29、set across the thickness of thespecimen. These plates are made of titanium carbide.Atype ofside-support plate that has been used in compression jigs to1800F (982C) is shown in Fig. 1(b) (4). This is an assemblyof small titanium carbide balls backed up by a titanium carbideplate. The balls protrude t
30、hrough holes in the front retainingplate. The holes for the balls are large enough to allow rotationand translation of each ball while at the same time retaining theballs in the plate assembly. The spacing of the balls, which isnormally about18 in. (3.2 mm), determines the minimumspecimen thickness
31、that can be tested without buckling be-tween the balls. Rational values of the ball spacing can beobtained from calculations based upon the plastic buckling ofsimply supported plates where the plate width can be taken asthe ball spacing. Another type of jig has a number of leaf-spring supports on ea
32、ch side of the specimen (3, 5). This designis limited to a temperature range in which the metal leaf-springelements can support the specimen satisfactorily. Jigs for usewith specimens that are heated by self resistance are discussedin Ref 1, 6 and 7, which also provide quantitative informationon the
33、 effects of lubrication, lateral-support pressure, springconstant, and misalignment.3.4.2 The side-support plates are assembled in a frame thatis part of the jig. A typical frame and jig assembly is shown inFig. 2.Afurnace is placed around the jig after the specimen andextensometer are assembled in
34、the jig. The holes in the supportblocks are for auxiliary cartridge-type heaters.4. Heating Apparatus4.1 The apparatus and method for heating the specimens arenot specified, but in present practice the following are mainlyused.4.1.1 The resistance of the specimen gage length to thepassage of an elec
35、tric current,4.1.2 Resistance heating supplemented by radiant heating,4.1.3 Radiant heating,4.1.4 Induction heating, or4.1.5 Convection heating with circulating-air furnace.4.2 The apparatus must be suitable for heating the specimenunder the conditions specified in Section 5.5. Test Specimen5.1 The
36、size and shape of the test specimen should be basedon three requirements as follows:FIG. 1 Specimen Side Support Plates (Ref 4)E209 00 (2010)25.1.1 The specimen should be representative of the materialbeing investigated and should be taken from the materialproduced in the form and condition in which
37、 it will be used,5.1.2 The specimen should be adapted to meet the require-ments on temperature control and rates of heating and strain-ing, and5.1.3 The specimen should be conducive to the maintenanceof axial alignment uniform application of force, and freedomfrom buckling when loaded to the end poi
38、nt in the apparatusused.5.2 The specimens are divided into two general classifica-tions: those with rectangular cross sections and those withround cross sections. The dimensions of the specimens areoptional. The specimen must be long enough to be compressedto the required deformation without interfe
39、rence from a sup-porting jig but not long enough to permit buckling where it isunsupported. The end allowance (dimension between the gagepoints and the adjacent end of the uniform section) should bea minimum of one half the width of rectangular specimens orone half the diameter of round specimens. T
40、ypical acceptablespecimens are illustrated in Fig. 3 and Fig. 4.5.3 When the dimensions of the test material permit, roundspecimens should be used. Round specimens should be de-signed to be free from buckling up to the end point of the testwithout lateral support. Rectangular specimens up to 0.250 i
41、n.(6.35 mm) thick normally require lateral support; with greaterthicknesses lateral support may not be required in well-alignedequipment. The methods covered by this specification arenormally satisfactory for testing sheet specimens down to0.020 in. (0.51 mm) thick. With smaller thicknesses inaccura
42、-cies resulting from buckling and nonuniform straining tend toincrease; consequently, extra care in the design, construction,and use of the test equipment is required to obtain valid resultsfor specimens in this thickness range. All compression speci-mens should be examined after they are tested; an
43、y evidence ofbuckling invalidates the results for that specimen.5.4 The width and thickness of rectangular specimens anddiameter of round specimens at any point in the gage lengthshould not vary from the average by more than 0.001 in. (0.025mm) for dimensions up to 1 in. (25.4 mm) or by more than 0.
44、1percent for dimensions above 1 in.5.5 The ends of end-loaded specimens should be parallelwithin 0.00025 in. (0.0064 mm) for widths, thicknesses, anddiameters up to12 in. (12.7 mm) and within 0.05 percent forwidths, thicknesses, and diameters above12 in. The ends ofend-loaded specimens should be per
45、pendicular to the sideswithin14 of a degree. All machined surfaces should have anaverage surface finish of 63 in. or better. RectangularFIG. 2 Typical Compression Testing Jig for Sheet SpecimensMounted on Support Jig (Ref 3)DimensionsSpecimen 1 Specimen 2 Specimen 3G.L.Gage Length, in. (mm) 1.000 6
46、0.005(25.46 0.13)2.000 6 0.005(50.86 0.13)2.000 6 0.005(50.86 0.13)LUniform Section, in. (mm) 2.500 6 0.005(63.56 0.13)3.000 6 0.005(76.26 0.13)2.50 min(63.5)WWidth, in. (mm) 0.625 6 0.010(15.96 0.25)1.000 6 0.010(25.46 0.25)0.500 6 0.010(12.76 0.25)E.A.End Allowance, in. (mm) 0.75 (19) 0.50 (12.7)
47、0.25 min (6.35)FIG. 3 Dimensions of Typical Rectangular SpecimensE209 00 (2010)3specimens should have a width of material, equal to at least thethickness of the specimen, machined from all sheared orstamped edges.5.6 Shouldered specimens may be used in lieu of specimenswith uniform width or diameter
48、, provided the method ofapplying force is consistent with requirements of axial align-ment, uniform application of force, and freedom from buck-ling.5.7 The surfaces of the rectangular specimens in contactwith the supporting jig should be lubricated to reduce friction.The lubricant should have negli
49、gible reaction with the surfaceof the specimen for the test temperature and time chosen andshould retain its lubricating properties for the duration of thetest. Molybdenum disulfide and graphite are examples oflubricants that are used.5.8 Specimen dimensions above 0.100 (2.54 mm) in. shouldbe measured to the nearest 0.001 in. (0.025 mm) or less;dimensions under 0.100 in. should be measured to the nearest1 percent or less. The average cross-sectional area of the gagelength should be used for calculation of stress.6. Temperature Control6.1 Conventional HeatingW
