Determination of paint film aging (artificial acceleration) (GB/T1865-80) This standard is applicable to the evaluation of the weather resistance of paint films. The artificial accelerated weather resistance Test Chamber is used to control a certain temperature, humidity, rainfall cycle and time. .Assess the grade according to the damage degree of the appearance of the test panel.
(1) Materials and equipment
①Artificially accelerated weather resistance Test Chamber
a. Light source: front w water-cooled tubular most lamp; distance between test board and light source: 35-40cm
b. Voltage stabilizing device: CZ-63 magnetic saturation voltage stabilizer or other voltage stabilizing devices.
②Test water: steaming water circulation for xenon lamp cooling, and ion exchange resin for rainwater purification.
③Other materials and inspection instruments and equipment are the same as the relevant regulations in "Determination of Atmospheric Aging of Paint Films" (GB/T1767)
(2) Test conditions
①Temperature: The air temperature in the working room is 45℃±2℃.
②Relative humidity: 65%-75%.
③Two cycles of drop: drop for 12 minutes every hour.
For special-purpose paints, the test conditions can be selected according to its use environment and requirements.
(3) Test procedure
①According to the product standard, select the substrate and supporting primer to prepare the test panel according to the "methods for damp heat resistance, salt spray, and aging paint film" (GB/T1765).
② Test two test panels for each variety, and record the original state of the test panels before testing.
③Put the test panel into the test panel fixture frame, insert it into the drum of the Climate Chamber, start the machine according to the operating procedures of the artificial climate knot, and conduct the test according to the test conditions.
④ Start to stop the machine every 48 hours to check the test plate, and then check it every 96 hours after 192 hours. After each inspection, the positions of the test plate and the bottom are exchanged.
⑤ The termination index should be determined according to the degree of aging and damage of various membranes and specific requirements. Generally, the test can be stopped when the damage of paint aging reaches any one of the "bad grades" in the comprehensive rating of "Paint Film Aging Test Evaluation Method" (GB/T1766).
(4) Inspection and rating of test panels
Remove the test panel. Dry the water drops on the back with a towel, put the front side up on the test cover to dry, and immediately calibrate the «Paint Film Aging Test Rating Method» (GB/T1766) for inspection and rating.
