ASTM C1326-2003 Standard Test Method for Knoop Indentation Hardness of Advanced Ceramics《高级陶瓷的努普压痕硬度的标准试验方法》.pdf
《ASTM C1326-2003 Standard Test Method for Knoop Indentation Hardness of Advanced Ceramics《高级陶瓷的努普压痕硬度的标准试验方法》.pdf》由会员分享,可在线阅读,更多相关《ASTM C1326-2003 Standard Test Method for Knoop Indentation Hardness of Advanced Ceramics《高级陶瓷的努普压痕硬度的标准试验方法》.pdf(9页珍藏版)》请在麦多课文档分享上搜索。
1、Designation: C 1326 03Standard Test Method forKnoop Indentation Hardness of Advanced Ceramics1This standard is issued under the fixed designation C 1326; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the Knoopindentation hardness of advanced ceramics.1.2 This standard does not purport to
3、address all of thesafety concerns, if any, associated with its use. It is theresponsibility 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:2C 730 Test
4、 Method for Knoop Indentation Hardness ofGlassC 849 Test Method for Knoop Indentation Hardness ofCeramic WhitewaresE 4 Practices for Force Verification of Testing MachinesE 177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE 380 Practice for Use of the International System of U
5、nits(SI) (the Modernized Metric System)E 384 Test Method for Microhardness of MaterialsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 European Standard:CEN ENV 843-4 Advanced Technical Ceramics, Mono-lithic Ceramics, Mechanical Properties at Room
6、 Tempera-ture, Part 4: Vickers, Knoop, and Rockwell SuperficialHardness Tests32.3 ISO Standard:ISO 9385 Glass and Glass CeramicsKnoop HardnessTest43. Terminology3.1 Definition:3.1.1 Knoop hardness number (HK), nan expression ofhardness obtained by dividing the force applied to the Knoopindenter by t
7、he projected area of the permanent impressionmade by the indenter.3.1.2 Knoop indenter, na rhombic-based pyramidal-shaped diamond indenter with edge angles of 172 308 and130 008.4. Summary of Test Method4.1 This test method describes an indentation hardness testusing a calibrated machine to force a
8、pointed, rhombic base,pyramidal diamond indenter having specified face angles,under a predetermined load, into the surface of the materialunder test and measures the surface projection of the longdiagonal of the resulting impression after removal of the load.NOTE 1A general description of the Knoop
9、indentation hardness testis given in Test Method E 384. The present test method differs from thisdescription only in areas required by the special nature of advancedceramics.NOTE 2This test method is similar to Test Methods C 730 and C 849,but differs primarily in the choice of load and the rate of
10、loading. Inaddition, the length correction factor for the resolution limits of opticalmicroscopes is not utilized.5. Significance and Use5.1 For advanced ceramics, Knoop indenters are used tocreate indentations. The surface projection of the long diagonalis measured with optical microscopes.5.2 The
11、Knoop indentation hardness is one of many prop-erties that is used to characterize advanced ceramics. Attemptshave been made to relate Knoop indentation hardness to otherhardness scales, but no generally accepted methods are avail-able. Such conversions are limited in scope and should be usedwith ca
12、ution, except for special cases where a reliable basis forthe conversion has been obtained by comparison tests.5.3 For advanced ceramics, the Knoop indentation is oftenpreferred to the Vickers indentation since the Knoop longdiagonal length is 2.8 times longer than the Vickers diagonalfor the same l
13、oad, and cracking is much less of a problem (1).5On the other hand, the long slender tip of the Knoop indenta-tion is more difficult to precisely discern, especially in mate-rials with low contrast. The indentation loads chosen in this test1This test method is under the jurisdiction of ASTM Committe
14、e C28 onAdvanced Ceramics and is the direct responsibility of Subcommittee C28.01 onProperties and Performance.Current edition approved October 1, 2003. Published November 2003. Originallyapproved in 1996. Last previous edition approved in 1999 as C 1326 99.2For referenced ASTM standards, visit the
15、ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from European Committee for Standardization, Brussels, Belgium.4Available from International
16、 Standards Organization, Geneva, Switzerland.5The boldface numbers in parentheses refer to the list of references at the end ofthis test method.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.method are designed to produce indentatio
17、ns as large as may bepossible with conventional microhardness equipment, yet notso large as to cause cracking.5.4 The Knoop indentation is shallower than Vickers inden-tations made at the same load. Knoop indents may be useful inevaluating coating hardnesses.5.5 Knoop hardness is calculated from the
18、 ratio of theapplied load divided by the projected indentation area on thespecimen surface. It is assumed that the elastic springback ofthe narrow diagonal is negligible. (Vickers indenters are alsoused to measure hardness, but Vickers hardness is calculatedfrom the ratio of applied load to the area
19、 of contact of the fourfaces of the undeformed indenter.)5.6 A full hardness characterization includes measurementsover a broad range of indentation loads. Knoop hardness ofceramics usually decreases with increasing indentation size orindentation force (load). The trend is known as the indentationsi
20、ze effect (ISE). Hardness approaches a plateau constanthardness at sufficiently large indentation size or forces (loads).The test forces or loads that are needed to achieve a constanthardness vary with the ceramic. The test force specified in thisstandard is intended to be sufficiently large that ha
21、rdness iseither close to or on the plateau, but not so large as to introduceexcessive cracking. A comprehensive characterization of theISE is recommended but is beyond the scope of this testmethod which measures hardness at a single, designated load.6. Interferences6.1 Cracking from the indentation
22、tips can interfere withinterpretation of the exact tip location. The loads chosen forthis test method are sufficiently low that tip cracking, if itoccurs, will cause tiny, rather tight cracks at the indentation tipsin advanced ceramics. Such cracks will have a negligibleinterference on measurements
23、of the long diagonal length (2)(unlike Vickers indentations in ceramics).6.2 Cracking or spalling from the sides of the Knoopimpression may also occur, possibly in a time-dependentmanner (minutes or hours) after the impression is made. Smallamounts of such lateral cracking have little or no influenc
24、eupon measured hardness, provided that the tip impressions arestill readable and the tips are not dislodged (2).6.3 Porosity (either on or just below the surface) mayinterfere with measuring Knoop hardness, especially if theindentation falls directly onto a large pore or if the indentationtip falls
- 1.请仔细阅读文档,确保文档完整性,对于不预览、不比对内容而直接下载带来的问题本站不予受理。
- 2.下载的文档,不会出现我们的网址水印。
- 3、该文档所得收入(下载+内容+预览)归上传者、原创作者;如果您是本文档原作者,请点此认领!既往收益都归您。
本资源只提供5页预览,全部文档请下载后查看!喜欢就下载吧,查找使用更方便
10000 积分 0人已下载
下载 | 加入VIP,交流精品资源 |
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- ASTMC13262003STANDARDTESTMETHODFORKNOOPINDENTATIONHARDNESSOFADVANCEDCERAMICS 高级 陶瓷 压痕 硬度 标准 试验 方法 PDF

链接地址:http://www.mydoc123.com/p-464240.html