The article "Pb-Free Solder Assembly for Mixed-Technology Boards" (CIRCUITS ASSEMBLY, March 2006) made several inaccurate and misleading statements in relation to the performance of the patented SACX alloy.
One of the specific advantages of SACX over SAC305 is the fact that SACX solder joints do not have micro-cracks or hot tear/shrink holes.
When using SACX we recommend soldering temperatures for single side boards of 255[degrees]C and for PTH 260[degrees]C.
Regarding the wetting times and temperatures, as the wetting balance study on page 44 of the March 2006 issue showed, SACX does not stand out as claimed.
Common alternative alloys are SN100C (3), SAC-LOW and SACX.
The SAC and SACX alloys dissolve most metals they come into contact with over time.
When the recommended soldering temperature is used, wetting is very similar between SN100C and SACX.