Knowledge before BGA operation

Knowledge before BGA operation

Knowledge before operation:
1. lead-free preheating temperature heating rate control in general 1.2~5 DEG C / S (s), the preheating

temperature is generally not more than 160 DEG C, heat preservation zone temperature control in the

160~190 DEG C, reflow peak temperature control in general 235~245 DEG C and the temperature

maintain time in 10 to 45 seconds, from heating up to the time of the peak temperature should be

maintained at about a minute and a half to two minutes.

2.Lead solder melting point is 183 degrees, and lead-free is 217 degrees. That is to say when the

temperature reaches 183 degrees, lead paste begins to melt, the melting point of the solder ball,

owing to their chemical properties will be higher than the solder paste.

3.Machine knowledge:

a.The application is wide: the upper air and the lower part of the dark infrared.

b.Three temperature area model: the upper air + the lower part of the hot air + dark infrared.

c.Aris appearance: the lower part of the upper + IR infrared dark points: different types of products the

heating mode, use temperature program exist different settings.