The lead-free IC product market demand is increasingly rising, traditional Sn63 /Pb37 solder paste, melting temperature for 183 deg.c, and lead-free solder paste, such as the melting point of Sn / Ag components into 216 to 221 DEG C, the corresponding reflow peak temperature must be increased, to ensure reliable connection. In actual work, set the benchmark of lead-free solder reflow furnace temperature curve as shown in figure.
In lead-free solder reflow furnace temperature curve setting benchmark
The object of value management, value management pro forma
T1 (s) for heating balance time of 40 -80 seconds within 150 to 195 DEG C time
T2 (second) time reflow melting time more than 15 seconds and 60 seconds above 225 DEG C
T3 (second) length of reflow time within 115 seconds of above 195 DEG C
P (c) reflow the maximum temperature of 225 more than 245 of the maximum temperature is less than 255 DEG C
S1 (C / s) for heating up the average slope gradient of 3 under 35 to 150 DEG C
S2 (C / s) reflow up to 195 degrees below the gradient of 3 degrees Celsius to the highest temperature of the average slope
be careful
The surface temperature of the substrate is up to 255 degrees Celsius, 225 -30 seconds above 15 degrees Celsius, above 230 degrees Celsius above 10 seconds, 240 above 10 sec;
Large special shaped components of the lowest 225 degrees, more than 13 seconds.