How to determine the hardness of automotive coatings

the hardness of the coating is one of the important properties that characterize the mechanical strength of the coatingAt present, the hardness determination method of swing rod is commonly used to determine the hardness of automotive coatingSwing bar hardness can be divided into single swing and double swing type, the former measurement in seconds, the latter in relation to the glass hardness percentagesingle-swinger, also known as Koenig and Bersaz swing rod hardnessSome large-scale automobile paint manufacturers abroad mostly use these two hardness tester, its automotive coatings, especially the hardness index of the paint, such as Masfu, Storak, Aksu and so onSeveral swing rod damping tests work in much the same way, that is, when the swing rod on the surface of the contact coating oscillates with a certain period, if the surface is softer, the swing ingress at the swing bar is attenuated faster and the slower the decayUsually the Cornelius hardness value is about half the hardness value of TheSazBecause the structure, weight, size, swing cycle and swing of the various swing rods are not the same, and the interaction between the swing rod and the coating also depends on the elasticity and viscous elasticity of the coating itself, so the determination of various swing results can not establish a conversion relationship between each other, so in the product standards listed the hardness value of the coating of the swing rod, must also indicate the type of swing rod useddouble-swing hardness meter is more commonly used in ChinaIts result is in terms of the ratio of the damping time of swing decay within the specified swing range to the damping time of swing attherite in the same swing angle range on the glass plateThe glass value must be determined before the double swing hardness meter can be measured