about solder ball

[menshawy]

hi all
what is the difference between Leaded and Lead-free Solder Balls
and which kind can i use for re-balling laptop bga chipset
thanks

[ktmmotocross]

Re: about solder ball

leaded melts about 180c and stand any heating from chip
lead free melts about 210c and cracking when repetive heated from chip

manufacturers using only lead-free solder balls. when reballing u replacing it with leaded

[menshawy]

Re: about solder ball

thanks friend
which is the best Qwin or Profound

[dellxps15]

Re: about solder ball

i use profound. leaded melt at 183 and more (depend on how accurate is the thermocouple) while lead free at 217 and more always depend on thermocouple, pcb and so son.. thin pcb need more degrees, while others need less.

i use 200° profile for lead free and 222-235 for lead free profile. always use flux for remove and resolder the bga. a good flux.

[menshawy]

Re: about solder ball

thanks friend

[bekirsalman]

Re: about solder ball

ALPHA® Solder Paste OM 5002 Chipset repair process is very practical and beautiful ( The only product I've used for years )

ALPHA OM 5002 Leaded Cream Solder 62-36-2

Alloy: Sn62 (62% Tin, 36% Lead, 2% Silver)

Metal Ratio: 90%

Solder Diameter: Type # 3 (20-45)

Flux Class: ROLO (IPC J-STD-004 Standard)

Halide Quantity: Does not contain

Residue Amount: Colorless, Very Low (no cleaning required)

Electrical Characteristics: Complies with IPC and Bellcore standards

Rheology: Suitable for Ragle and Closed System (min.0.4 mm range)

Printing Speed: up to 200 mm / sec

Working Temperature: 18-30 0C

Screen Life: 8 hours (without printing)

Adhesion Force: 1.5 gr / mm (at 50% humidity, 4 hours later)

Viscosity: M13 Malcom helical viscometer J-STD-005

[myth77]

Re: about solder ball

Up the topic...

I understand that leaded balls are better then lead-free balls made by manufacturer...but questoins...

1. If i will use bga chips with leaded solder balls......
When i remove old bga chip and then clean the surface and pads on the motherboard (with iron tip) do i use lead solder to clean it with? What about flux? can i use lead free flux? or with lead flux?

2. If i will use bga chips with lead-free solder balls...
When i remove old bga chip and then clean the surface and pads on the motherboard (with iron tip) do i use lead-free solder to clean it with? What about flux? lead-free flux?

Thank you!

[dellxps15]

Re: about solder ball

i always use leaded flux. we use leaded solder to clean pads to lower melting temperature of existing solder on pads.

generally we solder with lead free solder because solder is stronger and wont crack in long time use, but sometimes the process of reballing a new bga is the moment we kill new chip if bga are not moist free (no backing done)

[myth77]

Re: about solder ball

So, you use chips with lead-free solder balls? but you use leaded solder to clean pads?
And generaly you use leaded flux?

[dellxps15]

Re: about solder ball

99% of time i reball chip with leaded balls then solder it

and yes i always use leaded flux for desolder, clean ,solder.

i think best is backing chip before do any work with them.

ive soldered many bga without backing, but some chip after i solder it it just dont work.... or bad supplier or i need to backing the bga before do any work. now in winter time i wont do any ga rework and wait for better wheather.