1、中、日、德、英、美及國際標準規(guī)定的常用金屬材料對照表中國日本國際標準美國英國德國GB1220分GB1221類GB12228GB12229Gb12230JISISO683/13ISO683/16ANSIASTMBs970Bs1449DIN17440DIN17224鑄碳1WCAG5151 SCPH1A216 WCA161Cr-430FGS-C252ZG230-450 WCBG5151 SCPH2SC41(0A216 WCB素鋼3WCCA216 WCC合4ZG20CrMoA217 Wc53100 B2金鋼5G5151 SCPH21A217 Wc41504 621E6ZG15CrMoV3100 B37

2、ZG00Cr18Ni10G5121 SCS19AA351 CF31504 304C12E8ZGOCr18Ni9TiG5121 SCS13AA351 CF81504 304C15EG-X6CrNiMo1810鑄不9CF3MG5121 SCS16AA351 CF3M1504 316C12E10ZGOCr18Ni12Mo2TiG5121 SCS14AA351 CF8M1504 316C16E銹11CF8MG5121 SCS14AA744 CF-8M3100 316C16鋼12CF8CG5121 SCS21A351 CF8C1504 347C17EG-X7CrNiNb118913CF8G5121 SC

3、S13AG5121 SCS13A744 CF-83100 304C15G-X6CrNi18914CF3G5121 SCS19AA744 CF-33100 304C1215ZGOCr17Ni4Cu4NbG5121 SCS2417-4PH161Cr18Ni9SUS30212302,S30200302S25X12CrNi188170Cr18Ni9SUS30411304,S3400304S15X5CrNi1891800Cr18Ni10SUS304L10304L,S30403304S12X2CrNi189190Cr25Ni20SUS310S310S,S31008鍛200Cr17Ni12Mo2SUS316

4、20,20316,S31600316S16X5CrNiMo1810不銹211Cr18Ni12Mo2Ti320S17X10CrNiMoTi1810鋼220Cr18Ni12Mo2Ti320S17X10CrNiMoTi18102300Cr17Ni14Mo2SUS316L19,19316L,S31603320S12X2CrNiMo1810240Cr17Ni12Mo2NSUS316N316N,S31651250Cr17Ni4Cu4Nb17-4PHX2CrNiMoN1812260Cr17Ni13Mo2NSUS316LN27 0Cr18Ni12Mo2Cu2SUS316J1X10CrNiTi189281Cr1

5、8Ni9TiX10CrNiTi189290Cr18Ni10TiSUS32115321,S32100321S21 , 321S2C301Cr13SUS4103410,S41000410S21X10Cr13310Cr13SUS410S1410S403S17X7Cr13322Cr13SUS420J14420S,S42000420S37X20Cr13333Cr13SUS420J25420S45344Cr13SUS420J25431,S43100431S29X22CrNi1735 0ICr17Ni14Cu4NbSUS630B630,S17400X7CrNiA117736O0Cr25Ni20Mn3Mo3N

6、U3370Cr17Mn14Mo2NA4380OCr2ONi25Mo4Cu2904LUB639 0)0Cr15Ni60M16W4（哈氏C）40 0)Cr20Ni30Mo2Cu3（20號合金）0Ni70Cu30Mn（蒙耐爾）F面表是另外一個版碳素結(jié)構(gòu)鋼中國國際關(guān)美國日本德國英國法國原蘇耳GB/T700ISO3573ISO GOST 53fGOST380ASTMA283MASTMA573MASTMA284MASTMA709MJISJISG3101G3131JISG3106DINEN10025BS 970Part1BSEN10025NFEN10025630Q 195HR2CT1KPCT1CPCT1PC

7、Gr.BSS 330(SS34)SPHCSPHD040A10Q 215AHR1CT2KP-2CT2PC-2CT2CP-2Gr.CGr.58SS 330(SS34)SPHCFe 360 C040A12Fe 360 CFe 360 CQ 215BCT2KP-3CT2PC-3CT2CP-3Gr.CGr.58Gr.CSS 330(SS34)SPHCSPHD040A12Q235AFe360 ACT3KP-2CT3PC-2CT3CP-2Gr.DSS 400(SS41)SM 400A(SM41A)Fe 360 BFe 360 C080A15Fe 360 BFe 360 CFe 360 BFe 360 CQ

8、235BFe360 DCT3KP-3CT3PC-3CT3CP-3Gr.DSS 400(SS41)SM 400A(SM41A)Fe 360 BFe 360 C080A15Fe 360 BFe 360 CFe 360 BFe 360 CQ 235CFe360 DCT3KP-4CT3PC-4CT3CP-4Gr.DGr.65Gr.DSS 400A(SS41A)SM 400B(SM41B)Fe 360 C080A15Fe 360 CFe 360 CQ 235DFe360 DCT3KP-4CT3PC-4CT3CP-4SS 400A(SS41A)Fe 360D1Fe 360D2Fe 360D1Fe 360D

9、2Fe 360D1Fe 360D2Q 255ACT4KP-2CT4PC-2CT4CP-2Gr.36250SS 400(SS41)SS 400A(SS41A)Q 255BCT4KP-3CT4PC-3CT4CP-3Gr.36250SS 400(SS41)SS 400A(SS41A)Q 275Fe430 ACT5KP-2CT5CP-2SS 490(SS50)返回優(yōu)質(zhì)碳素結(jié)構(gòu)鋼項目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocT國際ISOASTMAISISAE(1)普通含鎰量鋼組05F10051005015A0305kn08F100610061006040A0408k

10、n08S09CK(S9CK)C10(1.0301),CK10(1.1121)100810081008050A040810F101010101010040A1010kn10S10CCK10(1.1121)101010101010040A10,XC1010050A10,060A10S12C101210121012040A12,050A12,060A12XC1215F040A1515kn15S15C,S15CKC15(1.0401),CK15(1.1141),Cm15(1.1140)101510151015040A15,050A15,060A1515S17C101710171017040A17,05

11、0A17,060A17XC1820F040A2020kn20S20C,S20CK102010201020050A20,060A2020S22CC22(1.0402),CK22(1.1151)102310231023040A22,050A22,060A2225S25C1025,10261025,10261025,1026060A25,080A25XC2525R683/IC25eS28C102910291029060A27,080A2730S30C103010301030060A30,080A30,080M30XC3230R683/IC30eS33C103510351035060A32,080A3

12、235S35CC35(1.0501),CK35(1.1181),1035,10371035,10371035,1037060A35,080A35XC3535R683/IC35eCm35(1.1180)項目FPMGB,YB1日本JIS德國DIN(W-Nr.)美國英國BS法國NF刖辦聯(lián)rocT國際ISOASTMAISISAE普通含鎰量鋼組S38C103810381038060A37,080A37XC3840S40C1040,10391040,10391040,1039060A40,080A40,080M4040R683/IC40eS43C1042,10431042,10431042,1043060

13、A42,080A42XC4245S45CC45(1.0503),CK45(1.1191),Cm45(1.1201)1045,10461045,10461045,1046060A47,080A47,080M46XC4545R683/IC45eS48C1045,1046,10491045,1046,10491045,1046,1049060A47,080A47XC48501050,10531050,10531050,1053080M5050R683/IC50eS53C105510551055060A52,080A5255S55CC55(1.0535),CK55(1.1181),Cm55(1.120

14、9)105510551055070M55,060A57,080A57XC5555R683/IC55e60S58CC60(1.0601),CK60(1.1221),Cm60(1.1223)106010601060060A62,080A6260R683/IC60e65106510651065060A67,080A67XC656570107010701070060A72,070A72,080A72XC707075107410741074060A78,070A78,080A787580108010801080060A82,080A83XC808085108410841084060A86,080A868

15、5項目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocT國際ISOASTMAISISAE(2)較局含鎰量鋼組15Mn17Mn4(1.8044)1016,10191016,10191016,1019080A15,080A1715r20Mn1021,10221021,10221021,1022080A20,070M20XC1820 r25MnS28C102610261026070M2625 r30MnS30C103010301030080A30,080A32XC3230 r35MnS35C103710371037080A3535 r40MnS40C40Mn4(1.5

16、038)1039,10401039,10401039,1040080A4040 r45MnS45C1043,10461043,10461043,1046080A4745 r50MnS53C1050,10531050,10531050,1053080A52,080M50XC4850 r60M6460 r65Mn15661566(1066)65 r70Mn1572157270 r返回碳素工具鋼項目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocT國際isoASTMAISISAET7SK7,SK6W1-71204Y275,1304Y375Y7

17、T8SK6,SK5W1-71/2Y8T8MnSK5Y8rT9SK4,SK5W2-81/2,W1-81/2WB1AY9T10SK3,SK4W2-91/2,W1-91/2BW1B1203Y290,1303Y390Y10T11SK3W1-101/21202Y2105Y11T12SK2W1-111/2BW1C1201Y2120Y12T13SK1W2-13,W1-121/21200Y2135Y13T7A1105Y165Y7AT8AC80W1(1.1525)(VDEh)1104Y175Y8AT8MnAC85WS(1.1830)(VDEh)Y8r AT9A1103Y1909YAT10AC105W1(1.15

18、45)(VDEh)Y10AT11A1102Y1105Y11AT12A1101Y1120Y12AT13AY13A返回合金結(jié)構(gòu)鋼項目中國日本德國美國英國法國 前蘇聯(lián)國際GB,YBJISDIN(W-Nr.)ASTMAISISAEBSNFrocTISO鎰鋼組09Mn209 r 210Mn21513151310 r 215Mn215 r 220Mn2SMn420(SMn21)102410241524(1024)150M1920 r 230Mn2SMn433(SMn1)28Mn6(1.5065),30Mn5(1.5066)133013301330150M2830 r 235Mn2SMn438(SMn2)3

19、6Mn5(1.5067)133513351335150M3635 r 240Mn2Smn443 (SMn3)13401340134040 r 245Mn2Smn443 (SMn3)13451345134545 r 250Mn2105210521552(1052)50 r(2)硅鎰鋼組27SiMn27Cr35SiMn37MnSi5(1.5122)35Cr42SiMn46MnSi4(1.5121)43Cr15MnV15MnV5(1.5213)(3)鎰鈕鋼組42Mn2V42MnVT(1.5223)(4)銘鋼組15CrSCr415 (SCr21 )5115511512C315X20CrSCr240 (

20、SCr22 )512051205120527A19,527M2018C320XR683/ 幻 430CrSCr430 (SCr2 )5130,51325130,51325130,5132530A30,530A3232C430X35CrSCr435 (SCr3 )34Cr4(1.7033),37Cr4(1.7034)513551355135530A3638C435XR683/ W 240CrSCr440 (SCr4)41Cr4(1.7035)514051405140530A40,530M4042C440XR683/ W 345CrSCr445 (SCr5)5147,51455147,514551

21、47,514545C445X50Cr51505150515050X(5)銘硅鋼組38CrSi38XC40CrSi40XC(6)銘鎰鋼組138CrMn16MC15Xr ,18Xr15CrMn20MnCr4(1.7147)20MC20 xr40CrMn40 xr項目中國GB,YB巳本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocT國際ISOASTMAISISAE7)銘鎰硅鋼組20CrMnSi20 xr c25CrMnSi25Xr C30CrMnSi30 xr c35CrMnSi35X r CA(8)銘鈕鋼組20CrV22CrV4(1.7513)20XA40CrV42CrV6(1.7

22、561)40XA A50CrVSUF1050CrV4(1.8159)615061506150735A5050CV450XA A(9)銘鎰鈦鋼 組30CrMnTi30Xr T(10)鋁鋼組16Mo15Mo3(1.5415)16M(11)銘鋁鋼組12CrMo13CrMo44(1.7335)1501-620Gr ? 2712CD412XM15CrMoSCM415(SCM21)16CrMo44(1.7337)A387Cr? 1212CD415XM20CrMoSCM420(SCM22)25CrMo4(1.7218)18CD420CD420XM30CrMoSCM430(SCM2)34CrMo4(1.722

23、0)41304130413030CD430XM35CrMoSCM435(SCM3)34CrMo4(1.7220)413541354135708A3735CD435XMR683/ n 242CrMoSCM440(SCM4)42CrMo4(1.7225)414041404140708M40,708A42,709M4042CD4R683/ n3SCM421(SCM23)R683/ 幻 7SCM418411841184118SCM44550CrMo4(1.7228)414541454145(SCM5)SCM822(SCM24)25CrMo4(1.7218)25CD438CrMoAISACM645(SA

24、CM1)34CrAIMo5(1.8507)905M3938XMo AR683/ X4(12)銘鎰鋁鋼 組15CrMnMo15CrMo5(1.7262)20CrMnMo20CrMo5(1.7264)18Xr M40CrMnMo414041404140708A4240Xr M,38Xr M(13)銘鎰鈕鋼 組12CrMoV12Cr1MoV24CrMoV24CrMoV55(1.7733)12XMP12X1M35書A項目35C(M中國ov日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocT國際ISOGB,YBASTMAISISAE(14)銀銘鋼組12CrNi2SNC415(SNC21)

25、10N11,16NC1112XH212CrNi3ASNC815(SNC22)14NiCr10(1.5732)(3415)665M1310NC12,14NC1212XH3A12Cr2Ni4A(E3310),(E3316)(3310),331612NC1512X2H2A20CrNi(3120)(3120)635M1520NC6 20XH20CrNi3A20NC11 20XH3A20Cr2Ni4A(3325)30NC1420X2H4A30CrNi3ASNC631(SNC2)(3435)653M3130NC11, 30XH3A30NC1237CrNi3ASNC836(SNC3)(3335)35NC15

26、40CrNiSNC236(SNC1)(3140)(3140)640M4035NC640XH45CrNi(A3145)(3145)45XH(15)銀銘鋁鋼組40CrNiMoASNCM439(SNCM8)43404340,(4337)4340,4337817M40,816M4040XMAR683/ 山 4SNCM220(SNCM21)862086208620805M2020NCD2R683/幻 12SNCM240(SNCM6)864086408640945M38,945A40R683/ 別J 1SNCM415(SNCM22)4315SNCM420(SNCM23)432043204320SNCM43

27、1(SNCM1)(4337)(4337)SNCM447(SNCM9)4347SNCM625(SNCM2)830M31SNCM815(SNCM25)835M15R683/幻 14(16)硼鋼組40BTS14B3540B50B36H40MnBTS14B35卜40MnBTS14B50 返回淬透性合金結(jié)構(gòu)鋼項目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocT國際ISOASTMAISISAESMn433H(SMn1H)1330H1330H1330HSMn438H1041H1041H1041H(SMn2H)SMn443H(SMn3H)1041H1041H1041HSCr4

28、20H(SCr22H)5120H5120H5120HSCr430H(SCr2H)5130H5130H5130H530H30SCr435H(SCr3H)5135H5135H5135H503H36SCr440H(SCr4H)5140H5140H5140H503H40SCM418H4118H4118H4118HSCM435H(SCM3H)4135H4135H4135H640H3530CD4SCM440H(SCM4H)4140H4140H4140H708H42SCM445H(SCM5H)4145H4145H4145HSNC631H(SNC2H)30NC11SNC815H(SNC22H)655H13SN

29、CM220H(SNCM21H)8620H8620H8620H20NCD*SNCM420H(SNCM23H)4320H4320H4320H項目中國日本德國美國ASTMAISISAE英國 法國 前蘇聯(lián) 國際返回彈簧鋼GB,YBJISDIN(W-Nr.)BSNFrocTISO65C67(1.0761)CK67(1.1231)1064,10651064,10651064,1065080A67XC656570C67(1.0761)CK67(1.1231)107010701070070A72XC707075C75(1.0773)107410741074070A78XC70,XC807585SUP31084

30、10841084080A868565Mn15661566(1066)65 r55Si2MnSUP655Si7(1.0904)925592559255250A5355S6,56S755C260Si2MnSUP765Si7(1.0906),66Si7(1.5028),60SiCr7(1.0961)926092609260250A58,250A6161S760C260Si2CrA67SiCr5(1.7103)9254925460C2XA50CrMnSUP955Cr3(1.7176)527A6050Xr50CrVASUP1050CrV4(1.8159)615061506150735A5050CV450

31、X0 A返回滾動軸承鋼項目中國GB,YB日本JIS德國VDEh美國英國BS法國NF前蘇聯(lián)rocT國際ISOASTMAISISAEGCr6105Cr2(1.3501)E5010050100100C3山X6GCr9SUJ1105Cr4(1.3503)E511005110051100534A99100C5山X9GCr15SUJ2100Cr6(1.3505)E521005210052100534A99100C6山X15GCr9SiMnSUJ3A485-Gr.1GCr15SiMn100CrMn6(1.3520)山 X15cr島速工具鋼項目中國日本德國美國英國法國前蘇聯(lián)國際ASTMAISISAEGB,YB

32、JISVDEhBSNFrocTISOW18Cr4VSKH2(S18-0-1)(1.3355)T1T1BT14201Z80WCV18-04-01P18SKH3S18-1-2-5(1.3255)T4T4BT44271Z80WKCV18-05-04-01SKH4AT5T5BT54275Z80WKCV18-10-04-02SKH4BT6T6BT6SKH10S12-1-4-5(1.3202)T15BT154175Z165WKCV12-05-05-04P10K5? 5SKH9S6-5-2(1.3343)M2M2BM24301Z85WDCV06-05-04-02SKH52M3-1M3-1SKH53S6-5-

33、3(1.3344)M3-2M3-2SKH54M4BM144361Z130WDCV06-05-04-04SKH55S6-5-2-5(1.3243)4371Z85WDKCV06-05-05-04-02SKH56M36M36SKH57S10-4-3-10(1.3207)W12Cr4V4MoS12-4(1.3302)P14? 4返回不銹耐酸鋼項目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocTASTMAISISAE10Cr13SUS405X7Cr13(1.4000)405405S1708X13(0X13)SUS429429SUS416416416S21Z12CF131

34、Cr17SUS430X8Cr17(1.4016)430430S15Z8C1712X17(X17)SUS430FX12CrMoS17(1.4104)430FZ10CF17SUS434X6CrMo17(1.4113)434434S19Z8CD17-011Cr28X8Cr28(1.4083)15X28(X28)0Cr17Ti08X17T(0X17T)1Cr17TiX8CrTi17(1.4510)1Cr25Ti25X25T(X25T)1Cr17Mo2TiX8CrMoTi17(1.4523)1Cr13SUS410,SUS403X10Cr13(1.4006),X15Cr13(1.4024)410,4034

35、10S21,403S17Z12C1312X13(1X13)SUS410SX7Cr13(1.4000)410SZ6C1308X13(0X13)2Cr13SUS420J1X20Cr13(1.4021)420420S37420S29Z20C1320X13(2X13)SUS420F420FZ30CF133Cr13SUS420J2420S45Z30C1330X13(3X13)4Cr13X40Cr13(1.4034)Z40C1440X13(4X13)1Cr17Ni2SUS431X22CrNi17(1.4057)431431S2914X17H2(1X17H2)9Cr1895X18(9X18)9Cr18MoV

36、X90CrMoV18(1.4112)SUS440A440ASUS440B440BSUS440C440CZ100CD17SUS440F440FSUS305X5CrNi1911(1.4303)305305S19Z8CN18-1200Cr18Ni10SUS304LX2CrNi18 9(1.4306)304L304L12Z2CN18-1003X18H11(000X18H11)0Cr18Ni9SUS304X5CrNi18 9(1.4301)304304S15Z6CN18-0908X18H10(0X18H10)1Cr18Ni9SUS302X12CrNi188(1.4300)302302S25Z10CN18

37、-0912X18H9(X18H9)2Cr18Ni917X18H9(2X18H9)SUS303X12CrNiS188(1.4305)303303S12Z10CNF18-09SUS303Se303Se303S1412X18H10E(X18H10E)時目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocTASTMAISISAESUS202202284S1612X17 r 9AH4(X17 r 9AH4)SUS301301301S21Z12CN17-070Cr18Ni9TiSUS321X10CrNiTi18 9(1.4541)321321S12Z6CNT18-1108X1

38、8H10T(0X18H10T1Cr18Ni9TiX10CrNiTi18 9(1.4541)321S20Z10CNT18-1112X18H10T(X18H10T)12X18H9T(X18H9T)1Cr18Ni11NbSUS347X10CrNiNb18 9(1.4550)347347S17Z10CNNb18-1008X18H12 E(0X18H12 e )SUS384384Z6CNC18-16SUS385385SUS XM7XM7Z6CNU18-10SUS XM15J1XM152Cr13Mn9Ni420X13H49(2X13H4 r 9)1Cr18Mn8Ni5N15X17A r14(X17A14)

39、0Cr18Ni2Mo2TiX10CrNiMoTi1810(1.4571)Z8CNDT17-1210X17H13M2T(X17H13M2T)1Cr18Ni12Mo2TiX10CrNiMoTi1810(1.4571)Z8CNDT17-1210X17H13M2T(X17H13M2T)SUS308308SUS309S309SSUS310S310S00Cr17Ni14Mo3SUS317LX2CrNiMo18 10(1.4438)317L317S12Z2CND19-150Cr18Ni12Mo3Ti320S17Z8CNDT17-131Cr18Ni12Mo3TiZ8CNDT17-13SUS317317317S

40、16SUS316X2CrNiMo18 10(1.4401)316Z6CND17-12SUS316LX2CrNiMo18 10(1.4404),X2CrNiMo18 12(1.4435)316L316S12Z2CND17-12,Z2CND17-1303X17H14M2(000X17H13M2)00Cr18Ni14Mo2Cu2SUS316J1L0Cr18Ni18Mo2Cu2TiX5CrNiMoCuTi1818(1.4506)SUS2012010Cr17Ni7AISUS631X7Cr1MiAI17 7(14568)631Z8CNA17-709X17H7fo|(0X17H7k)SUS630630返回耐

41、熱鋼項目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocTASTMAISISAE1Cr13Si3X10CrSi13(1.4722)1Cr18Si2X10CrSi18(1.4741)4421Cr13SiAIX10CrAI13(1.4724)10X13CO (1X125 )1Cr13SUS410,SUS403X10Cr13(1.4006)(DIN)X15Cr13(1.4024)(DIN)410,403410S21,403S17Z12C1312X13(1X13)2Cr1320X13(2X13)1Cr5Mo12CrMo19 5(1.7362)501,502Z12CD51

42、5X5M(X5M)ICrIIMoV15X11MIJ ) (1X11M A )4Cr9Si2SUH1X45CrSi9(1.4718)401S45Z45CS940X9C2(4X9C2)4Cr10Si2MoSUH3Z40CSD10,Z45CSD1040X10C2M(4X10C2M)1Cr18Ni9TiX10CrNiTi189(1.4541) (DIN)321S20Z10CNT18-1112X18H10T(X18H10T)12X18H9T(X18H9T)1Cr18Ni12Ti12X18H12T(X18H12T)1Cr23Ni13SUH309309309S24Z15CN24-1320X23H13(X23

43、H13)1Cr20Ni14Si2X15CrNiSi2012(1.4828)20X20H14C2(X20H14C2)1Cr25Ni20Si2SUH310X15CrNiSi2520(1.4841)310Z12CN25-2020X25H20C2(X25H20C2)4Cr14Ni14W2M o_45X14H14B2M(4X14H14B2ISUH31331S42Z25CNWS14-141Cr15Ni36W3TiXH35BTSUH35349S52SUH36349S54SUH37381S34SUH330330Z12NCS36-16SUH660660Z6NCTDV25-15BSUH661661SUH21CrA12 05(1.4767)(DIN)SUH409409SUH446446SUH4443S65Z80CSN20-02SUH11Z45CS9SUH600Z20CDNbV11SUH61661615X12BHM (1X12BHM )返回易切結(jié)構(gòu)鋼項目中國GB,YB日本JIS德國DIN(W-Nr.)美國英國BS法國NF前蘇聯(lián)rocT國際ISOASTMAISISAEY12SUM1211091109110910F2A12Y1510S20(1.0721)111911191119220M07Y20SUM3222S20(1.0724)20F2A20Y30