Reports on the comparisons made of three nitrogen capable ovens.The ovens range in size and price representative of common marketofferings. The ovens compared were forced convection type and oxygenconcentrations (02 ppm) were set at comparable levels. All of the ovenshave some exit cooling capability (nitrogen contained). Cards exitingthe oven may be oxidized to different levels, dependent on the card'stemperature. The level of oxidation sustained on the card's second sidedue to the first reflow operation and/or any intermediate process steps,e.g., misprinted paste strips, should be known. Downstream solderabilityand/or processability operations may be affected. Results from this workwere used to provide process engineering a quantifiable way of makingcapital expense decisions
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