How to test whether the dispensing effect is qualified?

With the development of the electronic industry, people's demands for high quality, high stability, and low failure rate of electronic products are constantly increasing. In addition, competition in the market is very fierce, and there is a risk of being snatched by competitors if there is a slight lag. Therefore, electronic production enterprises constantly improve their processes to improve product performance. As a result, the three proof paint spraying and dispensing machine has ushered in a huge market, More and more enterprises are using three proof paint spraying and dispensing machines to spray and dispense glue on electronic components, in order to achieve high stability and long service life.

When using three proof paint for spraying and dispensing, if the operation is improper or the process is not correct, the effectiveness of spraying and dispensing will be greatly reduced. How to check whether the spraying and dispensing are qualified?

JEENOCE introduces you to three commonly used methods:

1. Three proof paint salt spray test

(1) Test conditions

A temperature of 35 ± 2 ℃

Solution B: 5% sodium chloride solution, pH=6.5-7.2 (adjust with dilute hydrochloric acid or NaoH)

C Salt spray sedimentation rate 1-2mg/hour/80cm ^ 2

D spray mode Intermittent spray. That is to say, continuous spray for 8 hours, then stop heating, stop spray, and keep it for 16 hours under static and resting conditions (the last two hours are next week

The heating period is 24 hours per cycle.

E-cycle 6

(2) Test result: No bottom metal corrosion was found on the PCB circuit board.

2. Three proof paint mold test

(1) Test conditions

A temperature of 28 ± 0.5 ℃

B Relative humidity 98 ± 1%

The wind speed inside the C box is less than 0.2 meters/second

During the D test, there should be no 1mm water droplets on the surface of the sample.

The E-test box should be ventilated every 7 days for 3-5 minutes (during which time it may be monitored once outside the box)

F cycle of 28 days

(2) Test requirement: Grade O (no visible mold growth to the naked eye)

3. Moisture resistance test of three proof paint

(1) Test method: The 40 ℃ wet heat alternating test method is used as shown in the table below:

Stage temperature (℃) relative humidity (%) time (hours) total time (hours)

Heat up by 30 ℃ to 40 ℃ ≥ 85 (condensation) 1.5-2.0 16

High temperature and high humidity 40 ± 2 95 ± 3 14-14.5

Cooling by 40 ℃ to 30 ℃ ≥ 85 2-3 8

Low temperature and high humidity 30 ± 2 95 ± 3 5-6

(2) Cycle 14

(3) Testing requirements: The circuit board must not have blistering, peeling, metal rust or other phenomena of the coating, and must have the ability to protect against moisture and heat.