METALLURGICAL PROCESS FOR MANUFACTURING ELECTROWINNING LEAD AND LEAD ALLOY ELECTRODES

    公开(公告)号:CA2299419C

    公开(公告)日:2003-11-18

    申请号:CA2299419

    申请日:1998-08-04

    Abstract: Lead and lead-alloy anodes for electrowinning metals such as zinc, copper, lead, tin, nickel and manganese from sulfuric acid solutions, whereby the electrodes are processed by a repetitive sequence of cold deformation and recrystallization heat treatment, within specified limits of deformation, temperature and annealing time, to achieve an improved microstructure consisting of a high frequency of special low .SIGMA. CSL grain boundaries (i.e. 50 %). The resultant electrodes possess significantly improved resistance to intergranular corrosion, and yield (1) extended service life, (2) the potential for reduction in electrode thickness with a commensurate increase in the number of electrodes per electrowinning cell, and (3) the opportunity to extract higher purity metal product.

    SURFACE TREATMENT OF AUSTENITIC NI-FE-CR BASED ALLOYS

    公开(公告)号:AU2002220411A1

    公开(公告)日:2003-06-10

    申请号:AU2002220411

    申请日:2001-11-23

    Abstract: A surface treatment process for enhancing the resistance to intergranular corrosion and intergranular cracking of components fabricated from austenitic Ni-Fe-Cr based alloys comprising the application of surface deformation to the component, to a depth in the range of 0.01 mm to 0.5 mm, for example by high intensity shot peening below the recrystallization temperature, followed by recrystallization heat treatment, preferably at solutionizing temperatures. The surface deformation and annealing process can be repeated to further optimize the microstructure of the near-surface region. Following the final heat treatment, the process optionally comprises the application of further surface deformation (work) of reduced intensity, yielding a worked depth of between 0.005 mm to 0.01 mm, to impart residual compression in the near surface region to further enhance cracking resistance.

    Lead and lead alloys, with enhanced creep and/or intergranular corrosion resistance, esecially for lead-acid batteries and electrodes therefor.

    公开(公告)号:ZA200202668B

    公开(公告)日:2002-12-24

    申请号:ZA200202668

    申请日:2002-04-05

    Inventor: PALUMBO GINO

    Abstract: Recrystallized lead and lead alloy positive electrodes for lead acid batteries having an increased percentage of special grain boundaries in the microstructure, preferably to at least 50%, which have been provided by a process comprising steps of working or straining the lead or lead alloy, and subsequently annealing the lead or lead alloy. Either a single cycle of working and annealing can be provided, or a plurality of such cycles can be provided. The amount of cold work or strain, the recrystallization time and temperature, and the number of repetitions of such steps are selected to ensure that a substantial increase in the population of special grain boundaries is provided in the microstructure, to improve resistance to creep, intergranular corrosion and intergranular cracking of the electrodes during battery service, and result in extended battery life and the opportunity to reduce the size and weight of the battery.

    87.
    发明专利
    未知

    公开(公告)号:BR0014547A

    公开(公告)日:2002-06-04

    申请号:BR0014547

    申请日:2000-06-28

    Inventor: PALUMBO GINO

    Abstract: Recrystallized lead and lead alloy positive electrodes for lead acid batteries having an increased percentage of special grain boundaries in the microstructure, preferably to at least 50%, which have been provided by a process comprising steps of working or straining the lead or lead alloy, and subsequently annealing the lead or lead alloy. Either a single cycle of working and annealing can be provided, or a plurality of such cycles can be provided. The amount of cold work or strain, the recrystallization time and temperature, and the number of repetitions of such steps are selected to ensure that a substantial increase in the population of special grain boundaries is provided in the microstructure, to improve resistance to creep, intergranular corrosion and intergranular cracking of the electrodes during battery service, and result in extended battery life and the opportunity to reduce the size and weight of the battery.

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