Page 46 - Steel Tech India eMagazine Volume October 2023
P. 46

92/     Ć ,668(   Ć 2FWREHU

             JDYH  WKH  EHVW  SURSHUWLHV  LQ  WKH  UDQJH           03D
             \LHOG  VWUHQJWK              03D  WHQVLOH  VWUHQJWK  ZLWK
                          HORQJDWLRQ DQG WKH SURGXFW RI VWUHQJWK
             DQG GXFWLOLW\ EHWZHHQ       *3D   TXDOLI\LQJ IRU WKLUG
             JHQHUDWLRQ $+66   7KH  VWHHO  UH DXVWHQLWL]HG  EHWZHHQ
                        o
                 DQG     & VKRZ ORZ \LHOG VWUHQJWK     03D  DQG
             ultra high strength level with excellent ductility due to
             YHU\ KLJK UHWDLQHG DXVWHQLWH  ,Q WKH WHPSHUDWXUH UDQJH
                       o
                  WR      C,  show  ultra  high  strength  level  ranging
             EHWZHHQ        DQG        03D  EXW  UHWDLQV  UHDVRQDEO\
             JRRG HORQJDWLRQ EHWZHHQ   DQG     FRQIRUPLQJ WR ¿UVW
             generation AHSS.

             7DEOH      0HFKDQLFDO  3URSHUWLHV  RI  WKH  VWHHO  DW
             YDULRXV DQQHDOLQJ WHPSHUDWXUHV
                                                                )LJ     876 YV 7RWDO (ORQJDWLRQ 3ORW IRU WKUHH JHQHUDWLRQV
                   5H          YS    876    (O   <LHOG   876    $+66 ZLWK ([SHULPHQWDO GDWD
               DXVWHQLWL]DWLRQ    03D   03D      5DWLR    (O
                          o
              7HPSHUDWXUH  C                                    )UDFWRJUDSK\
               $V )RUJHG   $LU                                  7KH IUDFWRJUDSK\ RI WKH WHQVLOH WHVWHG VWHHO LQ DV IRUJHG
                  cooled                                        DQG  DLU  FRROHG  FRQGLWLRQ  DQG  DW  UH DXVWHQLWL]HG  WKUHH
                                     1100                       FRQGLWLRQV  DW  W\SLFDOO\     R&      R&  DQG     R&  LV
                                                                VKRZQ  LQ  )LJXUH    D   ±   G   7KH  DV IRUJHG  DLU  FRROHG
                                     1100
                                                                VWHHO  ZLWK  XOWUD  KLJK  VWUHQJWK         03D   DQG  JRRG
                                                        18.80
                                                                GXFWLOLW\        (O   VKRZV  ¿QH  GLPSOH  VWUXFWXUH   7KH
                                     1010               22.83   WHPSHUHG  PDUWHQVLWH  PLFURVWUXFWXUH  LQ  WKLV  FRQGLWLRQ
                                                                ZLWK ORZ UHWDLQHG DXVWHQLWH IDLOV E\ SXUH GXFWLOH PRGH
                                                                ZLWK  ¿QH  GLPSOH  LV  LQGLFDWLYH  RI  JRRG  GXFWLOLW\  DQG
                                                                WRXJKQHVV LQ WKH VWHHO  7KH IUDFWRJUDSK\ RI WKH VWHHO DW

                                                                    o
                                                                    & UH DXVWHQLWL]DWLRQ VKRZV ORZHU WHQVLOH VWUHQJWK
                                                  0.38
                                                                      03D  DQG EHWWHU GXFWLOLW\        ZKHUH WKHUH LV
                                                  0.38          FRPSOHWH GLPSOH UXSWXUH EXW WKHUH DUH FUDFNV UXQQLQJ
                                                                SHUSHQGLFXODU  WR  WKH  SODQH  RI  WKH  IUDFWXUH   7KH  ¿OP\
                   800                                          UHWDLQHG  DXVWHQLWH  LV       LV  DORQJ  WKH  WHPSHUHG
                                                                PDUWHQVLWH  ODWKV  DQG  GLႇHUHQWLDO  GHIRUPDWLRQ  DPRQJ
             The  SURGXFW  RI  XOWLPDWH  WHQVLOH  VWUHQJWK  DQG  WRWDO   WKH SKDVHV LV VHHQ  7KH VWHHO UH DXVWHQLWL]HG DW     C
                                                                                                               o
             HORQJDWLRQ RI WKH VWHHO DW GLႇHUHQW $57 F\FOH LV VKRZQ
             LQ  )LJXUH      7KH  VXSHULRU  FRPELQDWLRQ  RI  SURSHUWLHV    ZLWK D XOWUD KLJK VWUHQJWK       03D  DQG JRRG GXFWLOLW\
             i.e.,  strength  and  elongation  were  achieved  in  the          (O  ZKHUH WKH VWUHQJWK VKRZ IXOO\ GLPSOH UXSWXUH
             WHPSHUDWXUH UDQJH RI     WR     C due to the presence   DVVRFLDWHG  ZLWK  WHPSHUHG  PDUWHQVLWH  DQG  KLJKHVW
                                          o
             RI PD[LPXP DPRXQW RI UHWDLQHG DXVWHQLWH  7KLV FDQ EH   DPRXQW  RI  UHWDLQHG  DXVWHQLWH           IUDFWLRQ   7KHUH
             DWWULEXWHG WR WKH 75,3 HႇHFW RI WKH UHWDLQHG DXVWHQLWH   DUH  VPDOO  GLPSOHV  GXH  WR  WHPSHUHG  PDUWHQVLWH  DQG
             WUDQVIRUPLQJ  LQWR  PDUWHQVLWH  GXULQJ  GHIRUPDWLRQ   ,Q   WKH  ODUJHU  GLPSOHV  PD\  EH  DVVRFLDWHG  ZLWK  UHWDLQHG
                                                                                                            o
             addition to the retained austenite, bainitic phase also   DXVWHQLWH   7KH IUDFWRJUDSK\ RI WKH VWHHO DW     & UH
             contributes  to  the  enhanced  properties.  Hence,  it  is   DXVWHQLWL]DWLRQ  ZLWK XOWUD KLJK VWUHQJWK       03D  ZLWK
             LQIHUUHG WKDW WKH VWHHO LV KDYLQJ D QDUURZ UDQJH RI LQWHU   JRRG  GXFWLOLW\        (O    ,Q  WKLV  FRQGLWLRQ  WKH  UHWDLQHG
             FULWLFDO DQQHDOLQJ WHPSHUDWXUH IRU $57 WR DFKLHYH WKH   DXVWHQLWH  FRQWHQW  LV         LQ  D  WHPSHUHG  PDUWHQVLWH
             RSWLPXP  FRPELQDWLRQ  RI  PLFURVWUXFWXUDO  SKDVHV  IRU   PDWUL[  7KH IUDFWRJUDSK\ VKRZV GHHS GLPSOHV EXW WKHUH
             third generation AHSS properties.
                                                                DUH TXDVL FOHDYDJH IHDWXUHV

                                                                                                    STEEL TECH
   41   42   43   44   45   46   47   48   49   50   51