1、Designation: D 950 03Standard Test Method forImpact Strength of Adhesive Bonds1This standard is issued under the fixed designation D 950; 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 parent
2、heses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.INTRODUCTIONThe accuracy of the results of strength tests of adhesive bonds will
3、depend on the conditions underwhich the bonding process is carried out. Unless otherwise agreed upon between the manufacturer andthe purchaser, the bonding conditions shall be prescribed by the manufacturer of the adhesive. In orderto ensure that complete information is available to the individual c
4、onducting the tests, themanufacturer of the adhesive shall furnish numerical values and other specific information for each ofthe following variables:(1) Procedure for preparation of surfaces prior to application of the adhesive the cleaning anddrying of metal surfaces, and special surface treatment
5、s such as sanding which are not specificallylimited by the pertinent test method.(2) Complete mixing directions for the adhesive.(3) Conditions for application of the adhesive including the rate of spread or thickness of film,number of coats to be applied, whether to be applied to one or both surfac
6、es, and the conditions ofdrying where more than one coat is required.(4) Assembly conditions before application of pressure, including the room temperature, length oftime, and whether open or closed assembly is to be used.(5) Curing conditions, including the amount of pressure to be applied, the len
7、gth of time underpressure and the temperature of the assembly when under pressure. It should be stated whether thistemperature is that of the bond line, or of the atmosphere at which the assembly is to be maintained.(6) Conditioning procedure before testing, unless a standard procedure is specified,
8、 including thelength of time, temperature, and relative humidity.A range may be prescribed for any variable by the manufacturer of the adhesive if it can be assumedby the test operator that any arbitrarily chosen value within such a range or any combination of suchvalues for several variables will b
9、e acceptable to both the manufacturer and the purchaser of theadhesive.1. Scope1.1 This test method covers the determination of the com-parative impact strength of adhesive bonds in shear, whentested on standard specimens under specified conditions ofpreparation, conditioning, and testing.1.2 The va
10、lues stated in SI units are to be regarded as thestandard. The values in parentheses are for information only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safet
11、y and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:A 108 Specification for Steel Bars, Carbon, Cold-Finished,Standard Quality2B 16/B 16M Specification for Free-Cutting Brass Rod, Bar,and Shapes for Use in Screw Mac
12、hines3B 107/B 107M Specification for Magnesium-Alloy Ex-truded Bars, Rods, Shapes, Tubes, and Wire41This test method is under the jurisdiction of ASTM Committee D14 onAdhesives and is the direct responsibility of Subcommittee D14.80 on MetalBonding Adhesives.Current edition approved Oct. 1, 2003. Pu
13、blished October 2003. Originallyapproved in 1952. Withdrawn April 2003 and reinstated as D 950 03.2Annual Book of ASTM Standards, Vol 01.05.3Annual Book of ASTM Standards, Vol 02.01.4Annual Book of ASTM Standards, Vol 02.02.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Cons
14、hohocken, PA 19428-2959, United States.B 133 Specification for Copper Rod, Bar, and Shapes5B 139/B 139M Specification for Phosphor Bronze Rod,Bar, and Shapes3B 151/B 151M Specification for Copper-Nickel-Zinc Alloy(Nickel Silver) and Copper-Nickel Rod and Bar3B 211 Specification for Aluminum and Alum
15、inum-AlloyBar, Rod, and Wire4D 905 Test Method for Strength Properties of AdhesiveBonds in Shear by Compression Loading6D 907 Terminology of Adhesives6E 23 Test Methods for Notched Bar Impact Testing ofMetallic Materials73. Terminology3.1 DefinitionsMany terms in this test method are definedin Termi
16、nology D 907.3.2 Definitions of Terms Specific to This Standard:3.2.1 impact strength, nthe energy absorbed expressed injoules per square metre or foot-pounds-force (ft-lbf) per squareinch, by a specimen of standard design when impacted tofailure by a single blow of a testing-machine hammer. (Syn-on
17、ym impact value.)3.2.2 impact value, nSynonym for impact strength.4. Significance and Use4.1 Adhesives can fail under a sudden impact load and notunder a slowly applied load of the same or greater force.4.2 This test method can be used to compare the sensitivityof various adhesives to suddenly appli
18、ed loads.5. Apparatus5.1 Testing Machine:5.1.1 A pendulum-type impact machine with a hand veloc-ity of 3.4 m/s (11 ft/s), comprising essentially the following:5.1.1.1 Impact Head equipped with a flat striking faceslightly wider than the test specimen, aligned to strike thespecimen full-face.5.1.1.2
19、Jig to hold the test specimen, as shown in Fig. 1.The jig illustrated is not suitable for use with all impactmachines and vises. Vary the dimensions and design of the jigas required for adaptation to machines and vises available,provided the following general requirements are met: Machinethe jig fro
20、m a solid piece of steel and bolt it solidly to the baseof the testing machine. Drill the corners to ensure that the testspecimen sets flush against the retaining end of the jig.Minimize the dirt collection at the drilled corners which couldhold the end of the specimen away from the face of the jig.
21、Provide the jig with a screw to tighten the specimen in the jig,in order to minimize the tendency of the specimen to overturnwhen struck. Locate the jig so that the specimen will be struckat the point of maximum head velocity.5.1.1.3 Vise or Bolts to hold the jig rigid and immobileunder the stress o
22、f the testing machine hammer with the totalheight of the vise, jig, and test specimen such that the loweredge of the striking face of the impact head strikes thespecimen as near the adhesive line as possible, preferablywithin 0.79 mm (132 in.). Ordinarily the distance between thetop of the jaws of t
23、he vise of the machine and the bottom of thestriking face of the head is 22 mm (0.866 in.), and properheight of the specimen may be obtained by adjusting its heightin the jig.5.1.2 See Test Methods E 23 for additional information onimpact testing machines and their calibration.5.2 Conditioning Room
24、or DesiccatorsA conditioningroom capable of maintaining a relative humidity of 50 6 2%at 23 6 1.1C (73.4 6 2F), or desiccators filled with asaturated salt solution (Note 1) to give a relative humidity of 506 2 % at 23 6 1.1C.NOTE 1A saturated salt solution of calcium nitrate will give approxi-mately
25、 51 % relative humidity at the test temperature.6. Test Specimens6.1 Metal-to-Metal Specimens:6.1.1 MaterialMetals conforming to the following speci-fications are recommended:Metal DesignationBrass ASTM B 16, C36000; half-hard temperCopper ASTM B 133, C11000; hard temperAluminum ASTM B 211, A92024;
26、G-3Steel AISI 1020, G10200; cold-finished barPhosphor bronze ASTM B 139, C54400Magnesium ASTM B 107, AZ61A or M1A-FNickel silver ASTM B 151, C77000; quarter-hard6.1.1.1 Run tests on adhesives with high-impact strengthpreferably on steel to minimize deformation. The reuse ofspecimens is allowed, prov
27、ided that the face receiving theimpact is not deformed.6.1.2 Specimen Size, Shape, and AssemblyUse the testspecimen dimensions for metal-to-metal adhesives given inFig. 2(a), whenever possible. In cases where this specimencannot be fractured in the testing machine available, the squaredimensions of
28、the 25.4 by 25.4-mm (1 by 1-in.) block may bereduced to a smaller square, keeping the dimensions of the 25.4by 44.5-mm (1 by 134-in.) block constant. Clearly state thedimensions of the specimen and bonded area in the report(Section 9). In any case, it is desirable that the specimen sizebe such as to
29、 give impact strengths that fall somewhere near themiddle range of the testing machine, since readings in thehighest and lowest ranges are often unreliable. Assemble thespecimen so the face receiving the impact load is at the pointof maximum velocity of the impact head. The impact face ofthe specime
30、n is to be square and flat, perpendicular to the planeof the bond line, and parallel to the striking face of thependulum.6.1.3 BondingApply adhesive and pressure in accordancewith the procedure outlined by the manufacturer of theadhesive.6.1.3.1 Prepare areas that are to be bonded in accordancewith
31、the recommendations of the manufacturer of the adhesive.6.1.4 ConditioningPreconditioning is not required formetal-to-metal bonds. The adhesive is ready for test purposeswhen it has been applied in accordance with 6.1.3 unlessotherwise specified by the manufacturer or the purchaser.6.1.5 Number of T
32、est Specimens, Metal-to-Metal:5Withdrawn; see1995 Annual Book of ASTM Standards, Vol 02.01.6Annual Book of ASTM Standards, Vol 15.06.7Annual Book of ASTM Standards, Vol 03.01.D9500326.1.5.1 Test ten test specimens for each adhesive in the caseof metal-to-metal specimens.6.1.5.2 Discard specimens tha
33、t break at a flaw remote fromthe bond line. Retest unless such flaws constitute a variable theeffect of which it is desired to study.7. Testing Procedure7.1 Place the specimen in the jig in the vise of the impactmachine so that the specimen butts squarely against theretaining end of the jig. Rest th
34、e impact head of the machinegently against the specimen and adjust the jig so that the headfits squarely against the impact face of the specimen.7.2 Raise the impact head to a predetermined height andrelease the safety catch. The impact energy absorbed by thespecimen may then be read directly.7.3 Re
35、cord the following information:7.3.1 Record joules or foot pound-force of energy absorbedin producing failure of the specimen.7.3.2 Record bonded area of specimen.7.3.3 Record the percentages of cohesion, adhesion, andcontact failures (Note 2). This will be based on visual inspec-tion.NOTE 2Cohesion
36、 failure may be obtained by observing how much ofthe failure has occurred in the adhesive itself. That is, if the adhesive hasFIG. 1 Adapter Jig for Impact MachinesD950033adhered to the metal test pieces and no voids are visible, it represents a100 % cohesion failure. Adhesion failure refers to the
37、lack of adhering tometals being fastened. Contact failure refers to lack of bond lines being incontact due to uneven surfaces, poor pressure distribution, etc.8. Calculation8.1 Calculate the impact strength of the specimen as theenergy absorbed in producing failure of the specimen dividedby the bond
38、ed area of the specimen, and express in joules persquare metre or foot pound-force per square inch. Report thevalues to the nearest 100 J/m2(0.1 ftlbf/in.2). Unit resultscannot be extended to different areas than those tested.9. Report9.1 Report the following information:9.1.1 Complete identificatio
39、n of the adhesive tested, includ-ing type, source, manufacturers code numbers, form, etc.,9.1.2 Method of preparing test specimens, dimensions ofspecimens, and materials bonded,9.1.3 Average thickness of adhesive layer after formation ofthe joint, within 0.03 mm (0.001 in.). Describe the method ofob
40、taining the thickness of the adhesive layer including proce-dure, location of measurements, and range of measurements.9.1.4 Conditioning procedure used,9.1.5 Atmosphere conditions in test room,9.1.6 Number of specimens tested,9.1.7 Actual bonded area, and9.1.8 Maximum, minimum, and average value of
41、impactstrength, or the cohesion, adhesion, and contact failures for themetal specimens.10. Precision and Bias10.1 Precision and bias for this test is being determined andwill be available by September 2007.11. Keywords11.1 adhesive bonding; impact head; impact machine; im-pact strength; impact value
42、ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are
43、 entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standar
44、dsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committ
45、ee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).FIG. 2 Block Shear Impact Test SpecimensD950034
