Seven common defects and control methods in electroplating of automobile plastic trim

Car plastic trim partsThe common defects of electroplating process and control of automobile plastic electroplated parts mainly include the following seven types: pitting, pinholes, plastic leakage, yellowing, scorching, blistering and rust.

How to avoid the above defects, we must pay attention to the work in the electroplating process.

Pockmarks: small bumps or bright spots on the surface of a part, caused by small particles of solid impurities deposited on the surface of the two parts. It is usually caused by impurity in the electroplating water or solid impurities in the electroplating tank. It is recommended to use deionized water during the electroplating process to enhance the filtering effect of the electroplating solution.

Pinholes: small pits on the surface of the part, which are mainly formed by the hydrogen absorbed on the surface of the part not being released in time during the electroplating process. Generally, it is caused by uneven air agitation in the electroplating tank. By improving the air agitation, the hydrogen adsorbed on the surface of the part is driven away.

Exposure: The surface of the part is not plated, mainly because the front electroless nickel is not deposited, which causes the subsequent electroplating to be unsuccessful. The main possibility is that the electroplating tank is contaminated by the roughening solution, the chemical nickel reaction is not fast enough, and there is no partial deposition. The treatment method is to prohibit the roughening solution from being carried behind the plating tank to increase the concentration of the tank solution.

Yellow: The partial surface color of the part is yellow, mainly because the chromium layer (silver white) of the part is not plated, and the color of nickel (white to yellow) is exposed. Mainly chrome platingThe current is too small, just increase the chrome plating current.

Scorch: The sharp corners of the parts are protruding or rough, mainly due to the excessive current in the parts during the electroplating process and the roughness of the plating layer. The treatment method is to reduce the electroplating current in electroplating.

Bubbling: Air bubbles are formed on the surface of the part, which is mainly caused by the poor bonding between the electroplating layer and the plastic layer. The possible reason is that the performance of the injection material of the part is not good, and the part is not coarsened in place or excessive. It is recommended to select electroplating grade materials approved by the customer to appropriately increase or decrease the roughening level (increase the roughening concentration, temperature, time, etc.).

Rust: The surface of the part is corroded, discolored and loses its luster, which is mainly caused by the poor corrosion resistance of the part. This may be caused by electroplating hanger Poor conductivity causes insufficient plating film thickness and micropores, or the environment contains strong corrosive media (such as substances such as C1, S, etc.). Make new hangers and improve the process to ensure the thickness of the electroplating layer and the number of micropores, to avoid acid rain and frequent vehicle cleaning.

This is a simple analysis of seven common undesirable defects and methods to control defects. Many situations will be encountered during the electroplating process. The above analysis is only for your reference.