This is the picture of a car in Luoyang, Henan Province on June 13 after a sudden spontaneous combustion, only the frame of the car remains. This kind of scene has been happening frequently recently.
Will spontaneous combustion really occur when the car is exposed to high temperatures in summer?
First of all, I will tell you a terrible reality, that is, when the outdoor temperature reaches 40 degrees, the temperature inside the car can be as high as 70-90 degrees, especially black cars, because black is easier to absorb heat. However, under normal circumstances, the vehicle itself is not prone to spontaneous combustion under high temperature exposure, after all, the maximum temperature is still far from the ignition point.
So what exactly triggers the spontaneous combustion of a car?
If there is combustion, there must be combustibles, such as flammable materials such as lighters placed in the car. It is reported that when the environment exceeds 55°C, the volume of the lighter will expand, which will cause an explosion in a confined space and high temperature car. In addition, perfume and filling spray placed in the car are also a "time bomb", and there is a risk of explosion or burning.
In addition to the suspicion of these items placed in the car, the vehicle itself is also "to blame", after all, in hot weather, every part of the car may be in an overloaded state.
For example, there is oil leakage and liquid leakage in the oil circuit of the car; or a sudden short circuit in the vehicle line; or the high temperature in the engine compartment; Spontaneous combustion of the vehicle may occur due to the aging and cracking of the insulation layer of the wires and wiring in the vehicle. So in general, although the spontaneous combustion of cars is related to high temperatures, it is basically not directly related to summer exposure.
What harm will sun exposure bring to cars?
First of all, the most intuitive is the car paint. When the car is exposed to the sun for a long time, the paint on the car is easy to age and fade, which shortens the service life of the paint, not to mention the aesthetics. Secondly, tires made of rubber will also be affected by long-term high temperature exposure, and there will even be a risk of puncture in severe cases.
Even on the road surface of the highway, there are scattered fallen tire rings, which are caused by high temperatures. Therefore, when we drive the highway in summer, we often see the driver of a large truck in the service area, pouring water on the tires to cool down.
Finally, the interior of the vehicle is also affected. Because these interiors are basically made of plastic or leather, they can easily deform and soften when exposed to sunlight. In this regard, many people now choose to put sunscreen film on their cars.
So what is the principle of car sunscreen film?
Here is a structural diagram of the automobile heat insulation film, you can see that this layer of film has 7 layers, and the most important thermal insulation capacity is the third layer of metal thermal insulation layer. It is mainly composed of metal molecules such as aluminum and silver, which are coated on the safety layer by sputtering, and these metal layers will selectively reflect the infrared and ultraviolet rays in the sun, so as to achieve the effect of heat insulation.