Documents
Resources
Learning Center
Upload
Plans & pricing Sign in
Sign Out

Ductility in Aluminium Pressure Die Casting

VIEWS: 384 PAGES: 8

									                                               Ductility in Aluminium
                                               Pressure Die Casting
Aluminium in Cars
Between 1990 and 2000 the Aluminium                                                    Western Europe
Content of Passenger Cars built in Wes-                                250
tern Europe has risen from 50 to 100 kg
Al per car (Fig. 1). This is an average an-                                                   expected growth
nual consumption growth of 5 kg Al per
                                                  Average use kg/car
                                                                       200
car and year, or nearly 7%. It has to be
kept in mind that a substantial part of it
is recycled aluminium, saving energy                                   150
and raw materials while serving the Au-
tomotive Industry.
                                                                       100
An annual growth of 7% over a 10 years’
period is so remarkable that there must
be good reasons for this. To name just                                 50
the most important:
❑ Light weight to reduce fuel
                                                                        0
   consumption and CO2-emission                                          1990   1995   2000       2005            2010             2015
❑ Ductility to increase passive passen-
                                                                                                 Source: European Aluminium Association
   ger safety by energy absorption in
   case of crash                               Fig. 1 Average use of aluminium per car
❑ Ductility to allow cold forming joining
   techniques like self piercing riveting,
                                               coincidence. However, it was only in             Page 3 shows the Properties of Magsi-
   clinching etc, in part replacing wel-
                                               1994 when Silafont™-36, the first Duc-           mal™-59. Compared to Silafont™-36
   ding
                                               tile Pressure Die Casting Alloy, became          the percentage of Eutectic in Magsi-
❑ Fatigue Strength to cope with dyna-
                                               commercially available. Silafont™-36 is          mal™-59 is lower, making mold filling
   mic loads during lifelong car opera-
                                               a low iron alloy, avoiding sticking to the       more of a challenge to be mastered. The
   tion
                                               die. With the introduction of Silafont™-36       weldability is excellent but due to the
❑ Corrosion resistance to allow for
                                               at the GIFA-Show 1994 in Düsseldorf,             relatively high Magnesium content it
   uncoated chassis parts
                                               the ductility hurdle could be cleared.           takes skill and experience in welding
❑ Large Multifunctional Castings to
                                               Silafont™-36 paved the way to Structu-           technology, which has to be state of the
   reduce the number of components
                                               ral Parts for Aluminium Pressure Die             art.
   and thereby the assembly cost
                                               Castings.
❑ Recyclability to save Resources
                                                                                                For Pressure Die Cast Shops which are
                                               ASTM defines Ductility as the ability of a       mastering these challenges, there are
                                               material to deform plastically rather than       important tradeoffs:
Ductile Pressure Die Casting Alloys            fracture under stress. This is clearly
Silafont™-36 and Magsimal™-59                  what is needed for structural parts.             ❑ Magsimal™-59 has already in
Most of the Aluminium in Cars is in form                                                          Temper F, as cast, a very good
of pressure die castings. PDC is the cas-      Page 2 shows the properties of                     ductility (Fig. 6), avoiding cost
ting process with the highest productivi-      Silafont™-36. As may be seen in Tem-               expensive Heat Treatment
ty and the lowest variable cost. The high      per T4 or Temper T7 Elongations above
cost of investment for the PDC-equip-          15% are achieved. The excellent Casta-           ❑ Magsimal™-59 has a superior
ment is amortized by the big lot sizes         bility of Silafont™-36 makes it the favo-          Fatigue Strength
usual in the Automotive Industry. In ad-       rite Ductile Pressure Die Casting Alloy
dition to the cost advantage the rapid         for thin-walled castings of complex              Silafont™-36 and Magsimal™-59 are
solidification of the melt in the die yields   shape. Silafont™-36 tolerates conside-           from different alloy systems. They are
fine grained castings with uniform mech-       rable section size changes. In Temper F          not competing each other. Eventually it
anical properties. The historic porosity       a Yield Strength up to 150 MPa and an            depends on the demands profile of the
problem has been solved by Vacuum or           Elongation up to 10% are possible. If            casting, which alloy to take.
by Forced Venting. Blister-free Heat           higher values are required then a Heat
Treatment and Welding is today State of        Treatment has to be applied (Fig. 2).
the Art.
                                               A Fatigue Strength of 89 MPa makes it
The predominance of Pressure Die Cas-          right for Components under Dynamic
tings in the Automotive Industry is not by     Load.


                                                                                                                                          1
                                                                            Excellent Castability, no Sticking to the Die
Silafont -36                                                                Excellent Corrosion Resistance
                                                                            Excellent Weldability
                                                                            Suitable for Self Piercing Riveting and Clinching


                                                                                                                         300
 ™




                                                                                                                                   Magnesium
                                                                                                                         250            high          T6
                                                                                           Yield Strength Rp0,2 in MPa

                                                                                                                         200

                                                                                                                                               T5         Magnesium
                                                                                                                                                          low
                                                                                                                         150                                                 T7
                                                                                                                                                F
                                                   AlSi9MgMn




                                                                                                                         100
                                                                                                                                                                             T4


                                                                                                                         50



                                                                                                                          0
                                                                                                                               0           5              10           15          20          25
                                                                                                                                                     Elongation A in %

                                                                                  Fig. 2 Effects of magnesium contents and various treatments on yield
                                                                                         strength and elongation


                                                                                                                                                                                                                 others
                                            in %    Si               Fe              Cu                                            Mn               Mg                Zn                 Ti            Sr         total

                                            min.   9,5                                                                             0,5              0,1                                 0,04        0,010

                                           max.    11,5              0,15           0,03                                           0,8              0,5               0,08              0,15        0,020         0,2

  Fig. 3 Chemical composition limits


                                                                                                                                                                             Solidification Range       590 to 550 °C
                                           200                                                                                                                               Density                    2,64 kg/dm3
                                           180                              Plate thickness 4 mm, Temper F (as cast)                                                         Young’s Modulus            70 to 80 GPa
                                                                            Frequency 117 Hz, r = -1
      Alternating Stress [MPa], r = -1,0




                                                                                                                                                                             Coefficient of thermal
                                           160                              5%, 50%, 95% Probability to fracture
                                                                                                                                                                             expansion                  21·10-6/K
                                           140                                                                                                                               Thermal Conductivity       139 to 168 W/K·m
                                           120
                                                                                                                                                                             Electrical Conductivity    21 to 26 m/Ω·mm2
                                                                                                                                                    95%                      Shrinkage                  0,4 to 0,6 %
                                           100                                                                                                      50%
                                                                                                                                                     5%
                                           80                                                                                                                               Fig. 5 Physical Data
                                           60

                                           40

                                           20

                                             0
                                                               105                106                                                107                    108
                                                                       Number of Cycles [n]

  Fig. 4 Wöhler Curve



  2
Magsimal -59                                                            Excellent Castability, no Sticking to the Die
                                                                        Excellent Corrosion Resistance
                                                                        Excellent Weldability
 ™

                                                                        Suitable for Self Piercing Riveting

                                                                                   Wall Thickness                         Properties in Temper F (as cast)

                                                                                                                       Rp0,2                  Rm                        A
                                                                                         [mm]                         [MPa]                  [MPa]                     [%]

                                                                                        2 to 4                   160 to 220               310 to 340                 12 to 18
                                                                                        4 to 6                   140 to 170               250 to 320                  9 to 14
                                                                                        6 to 12                  120 to 145               220 to 260                  8 to 12
                                               AlMg5Si2Mn




                                                                               Fig. 6 Mechanical properties in Temper F as a function of Wall Thickness




                                                                                                                                                                             others
                                        in %    Si                Fe              Cu             Mn             Mg             Zn               Ti              Be            total

                                        min.   1,8                                               0,5            5,0

                                        max.   2,6                0,2            0,05            0,8            6,0            0,07           0,20         40ppm                0,2
  Fig. 7 Chemical composition limits


                                                                                                                                      Solidification Range       618 to 580 °C
                                        200                                                                                           Density                    2,63 kg/dm3
                                        180                               Plate thickness 4 mm, Temper F (as cast)                    Young’s Modulus            70 to 80 GPa
                                                                          Frequency 118 Hz, r = -1
                                                                                                                                      Coefficient of thermal
   Alternating Stress [MPa], r = -1,0




                                        160                               5%, 50%, 95% Probability to fracture
                                                                                                                                      expansion                  24·10-6/K
                                        140                                                                                           Thermal Conductivity       105 to 130 W/K·m
                                        120
                                                                                                                                      Electrical Conductivity    14 to 16 m/Ω·mm2
                                                                                                                 95%
                                                                                                                 50%
                                                                                                                                      Shrinkage                  0,6 to 1,1%
                                        100                                                                       5%                  Poisson number             0,325
                                         80
                                                                                                                                    Fig. 9 Physical Data
                                         60

                                         40

                                         20

                                          0
                                                            105                 106                 107                 108
                                                                        Number of Cycles [n]

  Fig. 8 Wöhler Curve



                                                                                                                                                                                      3
                           Silafont
                           Pressure Die Casting
Silafont -36
 ™

               AlSi9MgMn




                           Fig. 10 Mercedes-Benz S-Class Coupé, C-Pillar
                                   SilafontTM-36, Temper T7
                                   1,27 x 0,77 x 0,15 m, Wall thickness 2,5 mm, Weight 2,7 kg
                                   Producer: DaimlerChrysler, Mettingen




                           Fig. 11 Mercedes-Benz C-Class, Engine Cradle
                                   SilafontTM-36, Temper O
                                   0,92 x 0,58 x 0,17 m, Weight 10,2 kg
                                   Producer: DaimlerChrysler, Mettingen
                                                Honsel, Nürnberg


  4
Qualitätsmanagement-System QS9000




                           Fig. 12 BMW 3 series convertible, Frontend
                                   SilafontTM-36, Temper F
                                   1,25 x 0,35 x 0,4 m, Weight 5 kg
                                   Producer: BMW Group, Landshut




                                                                          Section of the flanged
                                                                          edge fixing the insert ring




                           Fig. 13 Damping Part
                                   SilafontTM-36, Temper F
                                   0,13 x 0,08 x 0,07 m , Weight 0,4 kg
                                   Producer: Fonderie Fasa, Paderno




                           Fig. 14 Yamaha R6, Rear swinging fork
                                   SilafontTM-36, Temper T5
                                   0,64 x 0,30 x 0,25 m, Weight 6,3 kg
                                   Producer: Yamaha, Japan



                                                                                                        5
Magsimal -59
 ™                          Magsimal
                            Pressure Die Casting
               AlMg5Si2Mn




                                   Fig. 15 Audi A4, Door Parts
                                           MagsimalTM-59, Temper F (as cast)
                                           Producer: AE-Group, Gerstungen




                                   Fig. 16 Alfa 166, Rear cross member
                                           MagsimalTM-59, Temper F (as cast)
                                           1,06 x 0,37 x 0,15 m, Weight 6,5 kg
                                           Producer: ThyssenKrupp Fahrzeugguss
                                                        KSM, Hildesheim




 6
                                          Fig. 17 Porsche Cayenne, Control arm,
                                                  MagsimalTM-59, Temper F (as cast)
                                                  0,37 x 0,32 x 0,06 m, Weight 0,9 kg
                                                  Producer: AE-Group, Gerstungen




Fig. 18 Porsche Cayenne, Compressor mounting,
        MagsimalTM-59, Temper F (as cast)
        0,33 x 0,23 x 0,075 m, Weight 0,45 kg
        Producer: Schweizer&Weichand, Murrhardt




Fig. 19 BMW 5 Series, Anti-sway bar suspension,
        MagsimalTM-59, Temper F (as cast)
        0,13 x 0,085 x 0,040 m, Weight 0,2 kg
        Producer: ThyssenKrupp Fahrzeugguss
                    KSM, Hildesheim


                                          Fig. 20 BMW 7 Series, Anti-sway bar suspension,
                                                  MagsimalTM-59, Temper F (as cast)
                                                  0,13 x 0,090 x 0,050 m, Weight 0,18 kg
                                                  Producer: Handtmann, Annaberg




                                          Fig. 21 Alfa 156, Rear cross member
                                                  MagsimalTM-59, Temper F (as cast)
                                                  0,97 x 0,17 x 0,22 m, Weight 3,4 kg
                                                  Producer: ThyssenKrupp Fahrzeugguss
                                                               KSM, Hildesheim




                                                                                            7
Fig. 22 Audi, Steering Wheel Skeleton before and after Impact Test
        MagsimalTM-59, Temper F (as cast)
        ø 0,36 x 0,12 m, Weight 0,736 kg
        Producer: Takata, Aschaffenburg




Fig. 22 Ford Range Rover, Inner Door Parts
        MagsimalTM-59, Temper F (as cast)
        1,0 x 0,24 m to 1,4 x 0,5 m
        Wall Thickness 2 to 3 mm, Weight 2,0 to 2,2 kg
        Producer: BMW-Group, Landshut
                    Metal Castings LTD, Worcester



8

								
To top