ASTM E2661 E2661M-20e1 用于航空航天应用的板状和平板复合结构的声发射检查标准实践.pdf

E2661/E2661M-201 NAS-410 NAS Certification and Qualification of Nonde- damage,growing flawsand friction-based sources.For addi structive Personnel(Quality Assurance Committee) tional information, see X1.3. SNT-TC-1A RemendedforPersonnel Qualification and 4.2 This practice provides an approach to determine the Certification of Nondestructive TestingPersonnel3 localregions of origin of the AE sources andany potential local 3. Terminology regions of large accumulation(s) of AE sources. 3.1 Definitions-See Terminology E1316 for general termi- 4.3 This practice can provide an approach to use AE-based nology applicable to this practice. criteria to determine the significance of flaws. 3.2 Definitions of Terms Specific to This Standard: 5. Significance and Use 3.2.1 characteristic damage state,n-transverse matrix cracking during the virgin loading of a posite;often 5.1 This AE examination is useful to detect micro-damage resulting in reaching a limit of the crack density prior to generation,accumulation,and growth of new orexisting faws. reaching failure. The examination is also used to detect significant existing 3.2.1.1 Discussion-Results in a reduction of stiffness of the damage from friction-based AE generated during loading or posite. For additional information, see X1.2. unloading of these regions. The damage mechanisms that can be detected include matrix cracking, fiber splitting,fiber 3.2.2fat panel posite,nany fiber reinforced pos- breakage,erpull-utbondingandlamination.During ite lay-up consisting of laminas (plies) with one or more loading,unloading,and load holding,damage that does not orientations with respect to some reference direction that result in a two-dimensionallyfat article of finite thickness (typically emit AE energy will not be detected. relatively thin). 5.2When the detected signals from AE sources are sufi- 3.2.3 plate-like posite,nany fiber-reinforced pos- ciently spaced in time so as not to be classified as continuous AE,this practiceis useful ...