1、Designation: D6110 17D6110 18Standard Test Method forDetermining the Charpy Impact Resistance of NotchedSpecimens of Plastics1This standard is issued under the fixed designation D6110; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, 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. Scope*1.1 This test method is used to determine the resistance of plastics to breakage by flexural shock as indic
3、ated by the energyextracted from standardized (see Note 1) pendulum-type hammers, mounted in standardized machines, in breaking standardspecimens with one pendulum swing. This test method requires specimens to be made with a milled notch (see Note 2). The notchproduces a stress concentration which p
4、romotes a brittle, rather than a ductile, fracture. The results of this test method are reportedin terms of energy absorbed per unit of specimen width (see Note 3).NOTE 1The machines with pendulum-type hammers have been standardized in that they must comply with certain requirements including a fixe
5、dheight of hammer fall, which results in a substantially fixed velocity of the hammer at the moment of impact. Hammers of different initial energies(produced by varying their effective weights), however, are recommended for use with specimens of different impact resistance. Moreover, manufacturersof
6、 the equipment are permitted to use different lengths and constructions of pendulums with possible differences in pendulum rigidities resulting (seeSection 5). Be aware that other differences in machine design do exist.NOTE 2The specimens are standardized in that they have a fixed length and fixed d
7、epth, however, the width of the specimens is permitted to varybetween limits. One design of milled notch is allowed. The notch in the specimen serves to concentrate the stress, minimize plastic deformation, and directthe fracture to the part of the specimen behind the notch. Scatter in energy-to-bre
8、ak is thus reduced. Because of differences in the elastic and viscoelasticproperties of plastics, however, response to a given notch varies among materials.NOTE 3Caution must be exercised in interpreting the results of this test method. The following testing parameters have been shown to affect test
9、results significantly: method of specimen fabrication, including but not limited to processing technology, molding conditions, mold design, and thermaltreatment; method of notching; speed of notching tool; design of notching apparatus; quality of the notch; time between notching and test; test speci
10、menthickness; test specimen width under notch; and environmental conditioning.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety, health, and environmental pra
11、ctices and determine the applicability ofregulatory limitations prior to use.NOTE 4This standard resembles ISO 179 in title only. The content is significantly different.1.3 This international standard was developed in accordance with internationally recognized principles on standardizationestablishe
12、d in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD647 Practice for
13、 Design of Molds for Test Specimens of Plastic Molding Materials (Withdrawn 1994)3D883 Terminology Relating to PlasticsD4000 Classification System for Specifying Plastic MaterialsD4066 Classification System for Nylon Injection and Extrusion Materials (PA)D5947 Test Methods for Physical Dimensions of
14、 Solid Plastics SpecimensE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method3. Terminology3.1 DefinitionsFor definitions related to plastics, see Terminology D883.1 This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the d
15、irect responsibility of Subcommittee D20.10 on Mechanical Properties.Current edition approved Dec. 1, 2017April 1, 2018. Published January 2018April 2018. Originally approved in 1997. Last previous edition approved in 20102017 asD6110 - 10.D6110 - 17. DOI: 10.1520/D6110-17.10.1520/D6110-18.2 For ref
16、erencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced
17、on www.astm.org.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 recommends that users c
18、onsult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohock
19、en, PA 19428-2959. United States14. Summary of Test Method4.1 A notched specimen is supported as a horizontal simple beam and is broken by a single swing of the pendulum with theimpact line midway between the supports and directly opposite the notch.5. Significance and Use5.1 Before proceeding with
20、this test method, refer to the material specification for the material being tested. Any test specimenpreparation, conditioning, dimensions and testing parameters required by the materials specification shall take precedence overthose required by this test method. Table 1 of Classification D4000 lis
21、ts theASTM materials standards that currently exist. If thereis no material specification, then the requirements of this test method apply.5.2 The pendulum impact test indicates the energy to break standard test specimens of specified size under stipulated conditionsof specimen mounting, notching (s
22、tress concentration), and pendulum velocity at impact.5.3 For this test method, the energy lost by the pendulum during the breakage of the specimen is the sum of the energies requiredto initiate fracture of the specimen; to propagate the fracture across the specimen; to throw the free ends of the br
23、oken specimen(toss energy); to bend the specimen; to produce vibration in the pendulum arm; to produce vibration or horizontal movement ofthe machine frame or base; to overcome friction in the pendulum bearing and in the indicating mechanism, and to overcomewindage (pendulum air drag); to indent or
24、deform, plastically, the specimen at the line of impact; and to overcome the frictioncaused by the rubbing of the striking nose over the face of the bent specimen.NOTE 5The toss energy, or the energy used to throw the free ends of the broken specimen, is suspected to represent a very large fraction
25、of the totalenergy absorbed when testing relatively dense and brittle materials. No procedure has been established for estimating the toss energy for the Charpymethod.5.4 For tough, ductile, fiber-filled, or cloth-laminated materials, the fracture propagation energy is usually large compared to thef
26、racture initiation energy. When testing these materials, energy losses due to fracture propagation, vibration, friction between thestriking nose and the specimen has the potential to become quite significant, even when the specimen is accurately machined andpositioned, and the machine is in good con
27、dition with adequate capacity (see Note 6). Significant energy losses due to bending andindentation when testing soft materials have also been observed.NOTE 6Although the frame and the base of the machine must be sufficiently rigid and massive to handle the energies of tough specimens withoutmotion
28、or excessive vibration, the pendulum arm cannot be made very massive because the greater part of its mass must be concentrated near its centerof percussion at its striking nose. Locating the striking nose precisely at the center of percussion reduces the vibration of the pendulum arm when usedwith b
29、rittle specimens. Some losses due to pendulum arm vibration (the amount varying with the design of the pendulum) will occur with tough specimenseven when the striking nose is properly positioned.5.5 In a well-designed machine of sufficient rigidity and mass, the losses due to vibration and friction
30、in the pendulum bearingand in the indicating mechanism will be very small. Vibrational losses are observed when wide specimens of tough materials aretested in machines of insufficient mass, or in machines that are not securely fastened to a heavy base.5.6 Since this test method permits a variation i
31、n the width of the specimens and since the width dictates, for many materials,whether a brittle, low-energy break (as evidenced by little or no drawing down or necking and by a relatively low energyabsorption) or a ductile, high-energy break (as evidenced by considerable drawing or necking down in t
32、he region behind the notchand by a relatively high energy absorption) will occur, it is necessary that the width be stated in the specification covering thatmaterial and that the width be stated along with the impact value.5.7 This test method requires that the specimen break completely. Results obt
33、ained when testing materials with a pendulum thatdoes not have sufficient energy to complete the breaking of the extreme fibers and toss the broken pieces shall be considered adeparture from standard and shall not be reported as a standard result. Impact values cannot be directly compared for any tw
34、omaterials that experience different types of failure.5.8 The value of this impact test method lies mainly in the areas of quality control and materials specification. If two groupsof specimens of supposedly the same material show significantly different energy absorptions, critical widths, or criti
35、caltemperatures, it is permitted to assume that they were made of different materials or were exposed to different processing orconditioning environments. The fact that a material shows twice the energy absorption of another under these conditions of testdoes not indicate that this same relationship
36、 will exist under another set of test conditions.6. Apparatus6.1 Pendulum Impact MachineThe machine shall consist of a massive base on which are mounted a pair of supports forholding the specimen and to which is connected, through a rigid frame and bearings, one of a number of pendulum-type hammersh
37、aving an initial energy suitable for use with the particular specimen to be tested (or one basic pendulum designed to accept add-onweights), plus a pendulum holding and releasing mechanism and a mechanism for indicating the breaking energy of the specimen.The specimen anvil, pendulum, and frame shal
38、l be sufficiently rigid to maintain correct alignment of the striking edge andspecimen, both at the moment of impact and during the propagation of the fracture, and to minimize energy losses due to vibration.The base shall be sufficiently massive so that the impact will not cause it to move. The mac
39、hine shall be designed, constructed,D6110 182and maintained so that energy losses due to pendulum air drag (windage), friction in the pendulum bearings, and friction and inertiain the indicating mechanism are held to a minimum.6.1.1 PendulumThe simple pendulum shall consist of a single or multi-memb
40、ered arm with a bearing on one end and a head,containing the striking nose, on the other. Although a large proportion of the mass of the simple pendulum is concentrated in thehead, the arm must be sufficiently rigid to maintain the proper clearances and geometric relationships between the machine pa
41、rtsand the specimen and to minimize vibrational energy losses, which are always included in the measured impact value. A machinewith a simple pendulum design is illustrated in Fig. 1. Instruments with a compound-pendulum design also have been found tobe acceptable for use. A compound-pendulum design
42、 is illustrated in Fig. 2.6.1.1.1 The machine shall be provided with a basic pendulum capable of delivering an energy of 2.7 6 0.14 J (2.0 6 0.10 ft-lbf).This pendulum shall be used for specimens that extract less than 85 % of this energy when breaking a specimen. Heavierpendulums or additional weig
43、hts designed to attach to the basic pendulum shall be provided for specimens that require more energyto break. A series of pendulums such that each has twice the energy of the next lighter one has been found convenient.6.1.1.2 The effective length of the pendulum shall be between 0.325 and 0.406 m (
44、12.8 and 16.0 in.) so that the requiredelevation of the striking nose is obtained by raising the pendulum to an angle between 60 and 30 above the horizontal.6.1.2 Striking EdgeThe striking edge (nose) of the pendulum shall be made of hardened steel, tapered to have an includedangle of 45 6 2 and sha
45、ll be rounded to a radius of 3.17 6 0.12 mm (0.125 6 0.005 in.). The pendulum shall be aligned in sucha way that when it is in its free hanging position, the center of percussion of the pendulum shall lie within 62.54 mm (0.10 in.)of the middle of the line of contact made by the striking nose upon t
46、he face of a standard specimen of square cross section. Thedistance from the axis of support to the center of percussion is determined experimentally from the period of motion of smallamplitude oscillations of the pendulum by means of the following equation:L 5g/4pi2!p2 (1)where:L = distance from th
47、e axis of support to the center of percussion, m,g = local gravitational acceleration (known to an accuracy of one part in one thousand), m/s2pi = 3.1416 (4pi2 = 39.48), andFIG. 1 Simple Beam (Charpy-Type) Impact MachineD6110 183p = period, in s, of a single complete swing (to and fro) determined fr
48、om at least 20 consecutive and uninterrupted swings. Theangle of swing shall be less than 5 each side of center.6.1.3 Pendulum Holding and Releasing MechanismThe mechanism shall be designed, constructed, and operated so that it willrelease the pendulum without imparting acceleration or vibration to
49、the pendulum. The position of the pendulum holding andreleasing mechanism shall be such that the vertical height of fall of the striking nose shall be 610 6 2 mm (24.0 6 0.1 in.). Thiswill produce a velocity of the striking nose at the moment of impact of approximately 3.46 m (11.4 ft)/s as determined by thefollowing equation:v 5=2gh (2)where:v = velocity of the striking nose at the moment of impact,g = local gravitational acceleration, andh = vertical height of fall of the striking nose.This assumes no windage or friction.6.1.4 Specimen SupportsThe test specimen s
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