Underbody Coating

UNDERBODY COATING

Introduction of Underbody Coating:

A Car Body is made up of several Metals such as Iron, Steel, Aluminum, Copper etc.

Rusting is the common term for corrosion of iron and its alloys. Corrosion is the reaction of Iron and Oxygen, as may present in Water or Air Moisture. Any Iron material when exposed to both oxygen and water is bound to rust, unless a preventive coating is applied on to it. A car’s underbody is exposed to the most wear and tear caused by muddy water, stones and other obstacles on the road. Because it’s not in plain sight, we often do not see the damage. Underbody Coating or Treatment offers a long term solution for issues related to corrosion and rust.

Modern Automotive Coating Processes

Modern automotive coating methods consist of five main steps. They include the following:‚Pretreatment: removes and cleans excess metal and forms an appropriate surface structureenabling bonding of a corrosion protection layer.‚The next step is electrodeposition (ED) of the anti-corrosion or rust prevention layer.‚A sealer like Poly Vinyl Chloride (PVC) is applied for anti-corrosion, elimination of water leaks,and minimization of chipping and vibrational noise.‚A primer is then applied to promote adhesion between the surface and the basecoat; it also impartsa smoother surface for subsequent layers and has anti-chipping properties.‚Finally, the topcoats that include a basecoat and clearcoat are applied; they providesurface properties that are sought after, including color, appearance, gloss, smoothness, andweather resistance.The areas of an automobile depicted in Figure 1 show where these five steps of coating and otheradditional coatings are used. As can be realized when examining this figure, a significant numberof specific coatings and materials are needed in addition to the above-listed steps to manufacturea salable automobile.

For the external surfaces of an automobile to be easily visualized, the five main steps of coatingproduce a layered structure depicted in Figure 2. These coatings are applied in a particular order andhave different material and protection or finishing functionalities; also, each layer relates to the othersand imparts a desired balance of properties

PRETREATMENT

ELECTRODEPOSITION

Rust-Proof Materials: Sealer/PVC

The third step is underbody coating (UBC) and seam sealing using PVC (Polyvinyl Chloride) and urethane. This sealing has multiple purposes, as shown in

CORROSION

Process and Types of Underbody Coating:

The underbody coating is a hard coating on the underbody of the car, which is fast-drying, paintable, rubberized, non-toxic and chip-resistant all along the underside of the car. we can also get a thinner clear coat underbody coating which is like a lacquer that coats the entire underside of the car. Some even inject rust-preventive coating material into crevices such as the bottom of doors and door sills, to protect them from rust.

Types:

1. Rubberized Undercoating

Rubberized vehicle undercoating is easy to apply and offers good cushioning as well as protection from dust, moisture, and dents. Which is generally the best option for protecting the vehicle’s underbody, as it provides the simplest and best protective measures against rust and moisture.

2. Polyurethane Undercoating

The other option for undercoating the vehicle is to use a polyurethane based sealant. This type of vehicle undercoating is a little bit quicker and easier to apply.This type of car undercoating generally requires a little bit more surface prep work before applying sanding and applying an etching primer to bare metals before using are generally recommended.

3. Wax or Paraffin-Based Undercoatings

A paraffin-based undercoating will be the cheapest and quickest option available with which to protect the undercarriage of the vehicle. However, keep in mind that it will wear off quicker than other types of undercoating and will need to be stripped and reapplied at least once every year.

4. Asphalt-Based Undercoating

For standard vehicles, any of the above mentioned types of undercoating will provide sufficient protection. For large trucks and heavy machinery, asphalt-based undercoating provides a bit of extra durability against rocks, chips, and moisture. This type of undercoating also needs more cure time than the other three, and is not paintable, making it best to use only for underbodies.

Some benefits of underbody coating:

Rust Prevention

Ideally any additional underbody coating should be applied when the car is brand new and clean. Car manufacturers use thick paints and sealants for the underbody, but adding an underbody coat especially in coastal cities is useful. Salt water tends to corrode cars really badly.

On bad roads, flying stones and pebbles can chip off the original underbody coating and leave the metal exposed. Using underbody coating offer extra protection.

Sound insulation

The thicker underbody coatings used on cars also act as effective sound dampeners. They can reduce road noise and tire noise and make the cabin seem quieter due to the sound absorptive nature of rubberized paints.

Easy maintenance

A uniform black underbody coating gives a car a clean look. It also makes the car easier to maintain by just hosing the underside down. You can be confident that slush build up won’t lead to rusting easily. Most underbody coats these days come with a five year warranty, which is the lifetime of such a coating.

Some of the downsides to underbody coating:

High cost

Cost of underbody coating has come down, but is still expensive. This is because underbody coating offered by a car dealer is one way in which they make money off the customer.

Risk of damage during application

Care must be taken while applying underbody coating. This thick rubberized paint if not applied properly, can get into moving mechanical parts and cause premature failure – such as into the U-joint or CV joints in a cars propeller shaft or drive shafts. They can also hinder smooth movement of suspension components, if applied incorrectly. And there’s also the risk of overspray on to the car’s paint finish on the lower edges of the car.

Below you could see the Pictures of with and Without Underbody coating images for better understanding.