Skip to main content
placeholder image

Fusion welding of rheocast semi-solid metal (SSM) processed aluminium alloy 7017

Journal Article


Abstract


  • Near-net shape casting of wrought aluminium alloys has proven to be difficult due to a

    tendency towards hot tearing during cooling. Rheocasting, or semi-solid metal (SSM) processing

    followed by high pressure die casting (HPDC), has recently been shown to be an effective

    alternative to conventional die casting, yielding near-net shape wrought aluminium alloy castings

    with less risk of hot tearing. This casting process involves pouring the liquid metal into a processing

    cup, which is then transferred into a coil for induction stirring and simultaneous forced air

    cooling. When the metal reaches the semi-solid casting temperature, the resultant slurry is

    transferred to a high pressure die casting machine and cast to near-net shape. This modifies the ascast

    microstructure, yielding a more globular primary phase and results in mechanical properties in

    the -T6 condition closely approaching those of wrought material in the same condition. Little

    information is currently available on the response of SSM-HPDC material to welding. This project

    investigated the influence of autogenous laser and gas tungsten arc welding on the microstructure

    and mechanical properties of aluminium 7017 after rheocasting. It is possible to successfully weld

    this material without solidification or liquation cracking. The effect of welding on the rheocast

    microstructure in the heat-affected zone and weld metal was shown, and the hardness and tensile

    properties of the resulting joints in the as-welded condition were tested and related to the

    microstructures achieved.

UOW Authors


  •   Du Toit, Madeleine
  •   Letsoalo, Patronica R. (external author)
  •   Moller, Heinrich (external author)

Publication Date


  • 2013

Citation


  • Du Toit, M., Letsoalo, P. & Moller, H. (2013). Fusion welding of rheocast semi-solid metal (SSM) processed aluminium alloy 7017. Solid State Phenomena, 192-193 161-166.

Scopus Eid


  • 2-s2.0-84870824603

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/3407

Number Of Pages


  • 5

Start Page


  • 161

End Page


  • 166

Volume


  • 192-193

Abstract


  • Near-net shape casting of wrought aluminium alloys has proven to be difficult due to a

    tendency towards hot tearing during cooling. Rheocasting, or semi-solid metal (SSM) processing

    followed by high pressure die casting (HPDC), has recently been shown to be an effective

    alternative to conventional die casting, yielding near-net shape wrought aluminium alloy castings

    with less risk of hot tearing. This casting process involves pouring the liquid metal into a processing

    cup, which is then transferred into a coil for induction stirring and simultaneous forced air

    cooling. When the metal reaches the semi-solid casting temperature, the resultant slurry is

    transferred to a high pressure die casting machine and cast to near-net shape. This modifies the ascast

    microstructure, yielding a more globular primary phase and results in mechanical properties in

    the -T6 condition closely approaching those of wrought material in the same condition. Little

    information is currently available on the response of SSM-HPDC material to welding. This project

    investigated the influence of autogenous laser and gas tungsten arc welding on the microstructure

    and mechanical properties of aluminium 7017 after rheocasting. It is possible to successfully weld

    this material without solidification or liquation cracking. The effect of welding on the rheocast

    microstructure in the heat-affected zone and weld metal was shown, and the hardness and tensile

    properties of the resulting joints in the as-welded condition were tested and related to the

    microstructures achieved.

UOW Authors


  •   Du Toit, Madeleine
  •   Letsoalo, Patronica R. (external author)
  •   Moller, Heinrich (external author)

Publication Date


  • 2013

Citation


  • Du Toit, M., Letsoalo, P. & Moller, H. (2013). Fusion welding of rheocast semi-solid metal (SSM) processed aluminium alloy 7017. Solid State Phenomena, 192-193 161-166.

Scopus Eid


  • 2-s2.0-84870824603

Ro Metadata Url


  • http://ro.uow.edu.au/eispapers/3407

Number Of Pages


  • 5

Start Page


  • 161

End Page


  • 166

Volume


  • 192-193