Six Testing Methods of Powder Bonding Effect

Powder coating bonding, mainly through friction heating or jacket heating to make the surface of powder particles have a certain degree of viscosity, so that the metal effect pigment and powder bottom powder combined. After the bonding of powder coating, we need to test the bonding effect. To this end, I would like to share with you six methods for testing the bonding effect of powder.

Method 1: spray plate observation
We take the bonded powder products, according to different voltage, air pressure spray plate, observe whether the effect of the plate is uniform and stable.

Method 2: horizontal spray line simulation
We can simulate the customer's on-site spraying process according to the process of small spraying line, and observe the gap between the board effect and the standard.

Method 3: visual observation
We can use a clean and transparent polyethylene plastic bag to connect the small half of the bag with the fixed powder. Put the air in the half of the bag and shake it several times before lifting it. Pat the upper part of the bag without powder gently. If the temperature is enough, the powder in the bag can be seen through fluoroscopy. The inner surface of the plastic bag can't see through the condition of the bag.

Method 4: instrument test
We can use magnifier, microscope and electron microscope to observe the state of powder and the condition of board surface.

Method 5: particle size analysis
According to the particle size distribution measured by the dry method particle size meter, we can observe whether the fine powder is significantly reduced before and after bonding, and whether the particle size distribution is more concentrated. If the fine powder is significantly reduced and the particle size distribution is more concentrated, the bonding effect is good.

Method 6: comparison of electron micrographs
According to the comparison between the electron micrograph of bonding base powder and metal effect pigment and that of bonding powder, the more metal effect pigment bonded on the powder particles, the better bonding effect.