基本信息
| 标准名称： | 金属氟塑料衬套 |
| 英文名称： | Bush for metal fluoroplastics |
| 中标分类： |
航空、航天 >>
航空器与航天器零部件 >>
管件、卡箍、密封件 |
| 发布日期： | 2003-02-24 |
| 实施日期： | 2003-02-24 |
| 首发日期： | 1900-01-01 |
| 作废日期： | 1900-01-01 |
| 出版日期： | 1900-01-01 |
| 页数： | 9页 |
适用范围
没有内容
前言
没有内容
目录
没有内容
引用标准
没有内容
所属分类： 航空 航天 航空器与航天器零部件 管件 卡箍 密封件
【英文标准名称】:StandardGuideforDevelopmentandUseofaGalvanicSeriesforPredictingGalvanicCorrosionPerformance
【原文标准名称】:预测电流腐蚀特性用电流系列的制定和使用的标准指南
【标准号】:ASTMG82-1998(2009)
【标准状态】:现行
【国别】:美国
【发布日期】:1998
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:G01.11
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:
【英文主题词】:active;corrosionpotential;galvaniccorrosion;GalvanicSeries;noble;passive;Acceleratedaging/testing--corrosion;Aluminum;Aluminumalloys--corrosiontesting;Austeniticsteel;Brass;Bronze;Cadmiummetals/alloys;Conductanceandconductivity(el
【摘要】:Whentwodissimilarmetalsinelectricalcontactareexposedtoacommonelectrolyte,oneofthemetalscanundergoincreasedcorrosionwhiletheothercanshowdecreasedcorrosion.Thistypeofacceleratedcorrosionisreferredtoasgalvaniccorrosion.Becausegalvaniccorrosioncanoccuratahighrate,itisimportantthatameansbeavailabletoalerttheuserofproductsorequipmentthatinvolvetheuseofdissimilarmetalcombinationsinanelectrolyteofthepossibleeffectsofgalvaniccorrosion.Onemethodthatisusedtopredicttheeffectsofgalvaniccorrosionistodevelopagalvanicseriesbyarrangingalistofthematerialsofinterestinorderofobservedcorrosionpotentialsintheenvironmentandconditionsofinterest.Themetalthatwillsufferincreasedcorrosioninagalvaniccoupleinthatenvironmentcanthenbepredictedfromtherelativepositionofthetwometalsintheseries.TypesofGalvanicSeries:OetypeofGalvanicSeriesliststhemetalsofinterestinorderoftheircorrosionpotentials,startingwiththemostactive(electronegative)andproceedinginordertothemostnoble(electropositive).Thepotentialsthemselves(versusanappropriatereferencehalf-cell)arelistedsothatthepotentialdifferencebetweenmetalsintheseriescanbedetermined.ThistypeofGalvanicSerieshasbeenputingraphicalformasaseriesofbarsdisplayingtherangeofpotentialsexhibitedbythemetallistedoppositeeachbar.SuchaseriesisillustratedinFig.1.Thesecondtypeofgalvanicseriesissimilartothefirstinthatitliststhemetalsofinterestinorderoftheircorrosionpotentials.Theactualpotentialsthemselvesarenotspecified,however.Thus,onlytherelativepositionofmaterialsintheseriesisknownandnotthemagnitudeoftheirpotentialdifference.SuchaseriesisshowninFig.2.UseofaGalvanicSeries:Generally,uponcouplingtwometalsintheGalvanicSeries,themoreactive(electronegative)metalwillhaveatendencytoundergoincreasedcorrosionwhilethemorenoble(electropositive)metalwillhaveatendencytoundergoreducedcorrosion.Usually,thefurtheraparttwometalsareintheseries,andthusthegreaterthepotentialdifferencebetweenthem,thegreateristhedrivingforceforgalvaniccorrosion.Allotherfactorsbeingequal,andsubjecttotheprecautionsinSection5,thisincreaseddrivingforcefrequently,althoughnotalways,resultsinagreaterdegreeofgalvaniccorrosion.Note8212;Darkboxesindicateactivebehaviorofactive-passivealloys.FIG.1GalvanicSeriesofVariousMetalsinFlowingSeawaterat2.4to4.0m/sfor5to15Daysat5to30x00B0;C(RedrawnfromOriginal)(seeFootnote5)ACTIVEEND
Magnesium
(x2212;)
MagnesiumAlloys
x2191;
Zinc
brvbar;
GalvanizedSteel
brvbar;
Aluminum1100
brvbar;
Aluminum6053
brvbar;
Alclad