Apparatus for assessing solderability

An apparatus for assessing solderability of a wiring board having a solderable through-hole, comprising:

• a jaw having an upper member with a first O-ring and a lower member with a second O-ring:
• means for positioning said jaw around said solderable through-hole, said upper and lower members of said jaw for clamping the wiring board with said O-rings forming a seal around said solderable through-hole on both sides of the wiring board;
• a reservoir containing an electrolyte;
• means for placing said electrolyte in contact with said solderable through-hole surrounded by said seal, said solderable through-hole forming a first electrode;
• a second, inert electrode and a third, reference electrode placed in contact with said electrolyte;
• means for connecting said first and second electrodes to a source of electric power;
• means for passing a current between said first and second electrodes for reducing metallic oxides present on said solderable through-hole;
• means for measuring current between said first and second electrodes and voltage between said first and third electrodes as a function of time during reduction of said metallic oxides, thereby identifying said metallic oxides present on said solderable through-hole;
• and
• means for assessing solderability of the wiring board based on said metallic oxides identified as present on said solderable through-hole by said voltage and current measurements.

An apparatus for assessing solderability of a wiring board having a solderable through-hole, comprising:

• a jaw having an upper member with a first O-ring and a lower member with a second O-ring:
• a centering pin for positioning said jaw members with said O-rings around said solderable through-hole, said upper and lower members of said jaw for clamping the wiring board with said O-rings forming a seal around said solderable through-hole on both sides of the wiring board:
• a reservoir containing a non-acidic electrolyte having no strong metal complexing agents;
• means for flushing said reservoir with inert gas to remove oxygen;
• means for placing said electrolyte in contact with said solderable through-hole surrounded by said seal, said solderable through-hole forming a first electrode;
• a second, inert electrode placed in contact with said electrolyte;
• a third, reference electrode placed in contact with said electrolyte in a separate compartment of said reservoir;
• means for connecting said first and second electrodes to a source of electric power;
• means for passing a current between said first and second electrodes for reducing metallic oxides present on said solderable through-hole;
• means for measuring current between said first and second electrodes and voltage between said first and third electrodes as a function of time during sequential reduction of said metallic oxides, thereby identifying said metallic oxides present on said solderable through-hole;
• and
• means for assessing solderability of the wiring board based on said metallic oxides identified as present on said solderable through-hole by said voltage and current measurements.