Often, magnesium die castings have such defects as local porosity, short-run, pouring defects, pin-holes, cracks, erosion scabs, not-complete formation of thin walls or profile, and others. Magnesium parts are subjected to phosphate pickling immediately after casting to protect against atmospheric corrosion. Repair of magnesium alloy casting by the flux brazing with the standard filler metal BMg-1 results in local melting of the base metal and the failure of phosphate coating. Two solders of Zn-Cu-Al and Zn-Cu-Al-Mg systems modified with grain refiners were used for healing casting defects by flux-free torch soldering in the temperature range of 400-500°C. Interaction between the solders and AZ91C base metal, microstructure of soldered joints, and protection from corrosion are among points of discussion.
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