Views: 42 Author: Site Editor Publish Time: 2020-06-03 Origin: Site
In recent years, metal surface treatment technology has developed rapidly and has been widely used in many fields.
In the surface treatment technology and engineering of powder coating equipment, pre-treatment occupies a very important position. It is not only indispensable as a "pre-treatment process" before surface treatment, but also closely related to the success or failure of subsequent surface treatment.
Therefore, it is necessary to eliminate various oil stains (such as lubricating oil, emulsion, grease, sweat, and dust) on the surface of the coated object before painting, and the cleaning process of making the coated surface clean is an indispensable process of pre-coating treatment process; What kind of chemical treatment or mechanical processing is carried out on the clean coated surface depends on the substrate and surface condition of the coated object and the coating process requirements.
The purpose of the salt spray test is to assess the corrosion resistance of the product or metal material against salt spray corrosion.
So what effect does the pretreatment process have on the salt spray test of the product?
The following Hanna Technology takes you to understand!
Salt spray test is generally divided into four types: neutral salt spray test (NNS test), acetate salt spray test (ASS test), copper salt accelerated acetate salt spray test (CASS test) and alternating salt spray test.
Usually we use the neutral salt spray test, which is the earliest and the most widely used test method for accelerated corrosion.
It uses 5% sodium chloride salt water solution, and the PH value of the solution is adjusted to the neutral range (6-7) as the spray solution.
The test temperature is 35 ℃, and the sedimentation rate of salt spray is required to be between 1-2ml/80cm2.h!
The simplest and fastest method can be used: salt spray corrosion test chamber.
Spray in the box to simulate the accelerated corrosion method of seawater environment, and the length of its withstand time determines the quality of the corrosion resistance!
Classification of salt spray test time of powder coating equipment:
example:
Within 300h-(processing methods such as degreasing, washing and drying, such as file cabinets, switch cabinets and anti-theft doors, etc.) within 300h-700h-(passive pickling and silane treatment can be used, such as the production of zinc steel guardrail factory)
Within 700h-1000h-(Electrophoresis + dusting / painting can be used, such as construction machinery and automotive exterior parts, etc.)
With the rapid development of my country's economy, the improvement of living standards and the enhancement of environmental protection awareness, customers have also put forward higher requirements for the products of plastic injection equipment itself.