Q:How do the automotive industry's requirements for coating thickness for chassis and body differ?
A:The thickness of the coating on the chassis and body of a car is significantly different:
The chassis is directly exposed to corrosion (salt, water, stone impact), so a thick coating of 60-100μm (hot-dip galvanizing) is required to ensure 10-15 years of protection;
The body takes both molding and corrosion protection into consideration, and mostly uses a thin coating of 10-40μm (electrogalvanizing), which relies on the paint layer to supplement and has a service life of 8-10 years.
Q:How big is the difference in coating thickness requirements for galvanized steel used outdoors and indoors in the construction industry?
A:Outdoor galvanized steel: strict requirements, the coating thickness is usually more than 60μm (such as Z120-Z275), it needs to withstand corrosion such as rain and ultraviolet rays, and the service life needs to be more than 10 years.
Indoor galvanized steel: the coating is thinner, generally 10-40μm (such as Z30-Z80), only moisture-proof, and the service life is 5-8 years.
Key difference: The outdoor environment is highly corrosive, and the coating needs to be thickened 2-3 times, while indoors only basic rust prevention is required.
Q:What factors affect the coating thickness requirements?
A:Core factors affecting the thickness requirements of the galvanized layer:
1. Environmental corrosiveness (for example, thicker coating is required in the ocean and industrial areas, and thinner coating can be used indoors);
2. Steel usage (structural load-bearing parts > decorative parts);
3. Design life (thicker coating is required for long-term protection);
4. Cost budget (thicker coating is more expensive).
In short: The stronger the corrosion, the more critical it is, and the longer it is used, the thicker the coating.
Q:What are the special requirements for coating thickness in the medical device industry?
A:The medical device industry has strict requirements on coating thickness, ensuring uniform thickness and a very small deviation, such as a nickel layer thickness of 5-10μm with a deviation of ±10%.
The coating thickness requirements for different devices vary, ranging from 20nm to 1000nm.
In addition, performance requirements such as biocompatibility, corrosion resistance, and wear resistance must be met to ensure the safety, effectiveness, and durability of the device.
Q:How do coating thickness requirements for food processing equipment differ from other industries?
A:The food industry has certain requirements for coating thickness. Generally, the coating thickness on the surface in contact with food should not be less than 5μm. At the same time, the coating thickness is required to be uniform to ensure good corrosion resistance, stability and hygiene, and to prevent food contamination due to insufficient local protection caused by uneven thickness.