Four products were selected based on the previous testing performed for the client. All four cleaners were diluted to 5% using DI water in 400 ml glass beakers. Two were also made into a 10 and 100% solution. All products were heated to 130 F on a hot plate. Table 1 lists the products evaluated and the corresponding concentrations.
Eighteen preweighed coupons were coated with the flux and heated to 100 F for one hour in an oven. After cooling to room temperature, a second weighing was performed to determine the amount of contamination present on each coupon. The cleaning solution was placed in a Crest 40 kHz ultrasonic tank model 4Ht 1014-6 filled with water heated to 130 F and degassed for five minutes. Three coupons were placed into the suspended beaker and cleaned for five minutes. Coupons were rinsed in DI water at 130 F for 30 seconds and dried using a Master Appliance Corp, Hot-air gun model HG-301A at 500 F for 30 seconds. Once the coupons returned to room temperature, final clean weights were recorded and cleaning efficiencies were calculated.
SUBSTRATE MATERIAL: Brass Coupons 260
CONTAMINANTS: Kester Solder 1544 Rosin Flux-(Ethanol CAS#64-17-5;2-Butanol CAS#78-92-2*;Modified Rosin CAS#8050-09-7)
CONTAMINATING PROCESS USED: Coupons coated using hand-held swab and then dried in an oven at 100 F for one hour.
The use of ultrasonic energy greatly increased the efficiencies of all the solutions tested. Only one solution, Bio-T at 5% dilution had an efficiency lower than 95%. Table 2 lists the results for each cleaner and concentration.
Table 2. Cleaning Effectiveness
|
|
Armakleen
|
Safey Wash 5
|
SW 10
|
Bio-T 5
|
Bio-T 100
|
Inproclean
|
| Coupon 1
|
100.06
|
97.58
|
99.85
|
71.97
|
100.09
|
100.27
|
| Coupon 2
|
100.00
|
91.38
|
100.00
|
44.69
|
100.00
|
95.61
|
| Coupon 3
|
99.76
|
96.47
|
99.61
|
18.37
|
100.22
|
99.78
|
| Average
|
99.94
|
95.14
|
99.82
|
45.01
|
100.10
|
98.55
|
All of the products tested were very effective in removing nearly all of the flux from the coupons. The increased concentrations for Safety Wash CRC and Bio-T 300 B proved to be as effective as the Armakleen and Inproclean 4000 T at 5%. These four solutions will be used to clean the supplied client parts.