Elaboration and Mechanical-Electrochemical Characterisation of Open Cell Antimonial-lead Foams Made by the “Excess Salt Replication Method” for Eventual Applications in Lead-acid Batteries Manufacturing

In this study, open cell 25 % antimony-lead alloy foams are fabricated for possible use to lighten thick plates of lead-acid batteries. A new inexpensive and simple variant of the salt replication process is developed and explored. Different morphology and shapes have been successfully obtained with “excess salt replication” method (abbreviated as ESR method). Best porosity of about 68 % is obtained with salt particles size of about 3 mm. SEM and EDXS investigation of the composite salt/antimony alloy before NaCl leaching revealed the presence of the lead oxides microfilm coating cell walls and becoming lead carbonates after salt removal. Uniaxial compressive behaviour of the resulting cellular materials is studied for foams with porosities between 45 % and 70 %, and salt grain size ranging between 2.5 and 5 mm. A higher plateau stress is reached compared to the results obtained in the literature working on the aluminium foams. The reproducibility of the process is proved along samples.

Determination of Antimony, Tin, and Arsenic in High Antimonial Lead Alloys by Vacuum X-ray Fluorescence

A method of x-ray fluorescence analysis for high antimonial lead alloys has been developed to cover antimony concentrations between 6 and 18%, a range not covered in previously published x-ray methods. The proposed method utilizes a General Electric XRD 6 VS spectrometer, chill-cast mold, and a special cutting bit to produce a smooth surface. Ten separate 10-sec counts are taken at 120° intervals to offset nonhomogeneity of the surface. Average counts vs concentration are plotted to obtain calibration curves and percentage concentration. The precision and accuracy of the proposed method compare favorably with the classical wet method. The average standard deviation of the proposed method in terms of the amount present is 1.19% for antimony, 2.03% for tin, and 2.37% for arsenic. These values are within the limits required in the specifications of most high antimonial lead alloys. A time saving of 2 h per sample is realized by the x-ray method over the classical wet method.