Film performance inspection - Preparation of test plate

1. Preparation of test sample

(1) The material and size of the test sample substrate of the fluidized bed dip coating method (GB6554-86) are specified as follows:

Type A1: cold-rolled steel plate, the size is 1mmx150mmx200mm.

Type A2: cold-rolled steel plate , the size is 1mmx75mmx100mm.

Type B: steel, the size is 10mmx10mmx150mm, ground into a square with sharp edges, the size is accurate to 0.025mn. The steel should meet the requirements of GB700-79 "Technical Conditions for Ordinary Carbon Structural Steel".

The number of samples and coating thickness of some test items are specified in Table 10_1, and can also be prepared according to US requirements. Items with special requirements for samples will be explained separately in this item.

Before coating, the substrate should be degreased and cleaned with a suitable solvent. The surface should be smooth and free of rust.

It is recommended to prepare test specimens by a fluidized bed coating process.

(2) Test sample of electrostatic spraying method (HG/T2597, HG/T2006-91)

Use the steel plate specified in GB/T1727, and carry out phosphating process after derusting and degreasing. Except for steel plates for acid resistance, alkali resistance, salt spray resistance, heat and humidity resistance, adhesion and cupping tests, tinplate is used for other tests.

The preparation of the paint film is to put the blank sample in the powder spraying cabinet, spray the Spray Gun, high-voltage electrostatic generator, powder spraying cabinet, powder recovery device, Air Compressor and other equipment, and keep the sprayed sample vertically, put it in the Curing is carried out in a blown constant temperature Drying Oven (according to the specified temperature and time, and the thickness of the paint film is also controlled by technical regulations). Then, after being placed in a constant temperature oven for 24 hours, the performance test is carried out according to relevant methods.