Thermal conductive silicone grease will release harmful substances in high temperature environment?

When using thermal grease in ovens, microwave ovens, outdoor LED lights and other high-temperature equipment, many people will worry: a high temperature, silicone grease will release toxic substances. In fact, whether the thermal conductive silicone grease is safe at high temperature depends on the composition and quality. If you choose the right product and use the right scene, you can avoid the problem of harmful substance release. Today, from the composition, test data, the purchase method of three aspects, analysis of the safety of thermal grease in high temperature environment.

First of all, it should be clear: the compliance of the thermal grease, high temperature will not release harmful substances. The basic components of high-quality silicone grease are "silicone resin" and "non-metallic thermal conductive filler", both of which have good high temperature stability. The upper limit of temperature resistance of silicone resin can reach above 200 ℃, and it will not decompose at high temperature to produce toxic gas; while non-metallic fillers such as alumina and boron nitride are stable inorganic compounds, even if they are in the environment of 100-150 ℃ for a long time, they will not release heavy metals or harmful volatiles. For example, Huaneng Zhiyan HY410, HY610 and other compliant silicone greases, after SGS high-temperature volatilization test, are continuously heated at 150 ℃ for 24 hours, the volatile matter is only 0.3, and the volatile component is harmless small molecule silicone oil, does not contain formaldehyde, benzene, heavy metals and other harmful substances, and fully meets the national environmental protection standards.

But be alert to the high temperature safety hazard of "inferior silicone grease. Some low-cost silicone grease on the market, in order to reduce costs with "industrial waste oil" instead of high-quality silicone resin, or add lead, mercury poor quality filler. This type of silicone grease will quickly decompose at high temperatures, releasing pungent toxic gases (such as formaldehyde, volatile organic compounds), which will not only stimulate the respiratory tract, but may also adhere to the inside of the device and corrode metal parts. Some users used inferior silicone grease for the oven temperature control module. After high-temperature use, they smelled burnt. When they opened it, they found that the silicone grease had turned black and carbonized, and the internal parts of the equipment were rusted. After testing, the volatiles contained excessive lead elements. Fortunately, they were replaced in time, which did not cause more harm.

To judge whether silicone grease is safe under high temperature environment, two "core indicators" can be referred ". One is the "high temperature volatilization rate". The volatilization rate of compliant products should be ≤ 0.5/150 ℃/24h. The lower the value, the more stable it is at high temperature and the less substances released. The second is "environmental protection certification". Silicone grease that has passed RoHS, SGS and other authoritative certification is preferred. Such products will be clearly marked "free of heavy metals" and "harmless at high temperature" with detailed component test reports. For example, Huaneng Zhiyan HY610 has a high-temperature volatilization rate of only 0.2. It has passed RoHS 2.0 certification and is used on 120-150 ℃ high-temperature equipment such as microwave ovens and ovens. It will not release harmful substances at all.

There are two "safety points" for using silicone grease in high temperature scenarios ". First, select the right temperature-resistant model, and select silicone grease with higher temperature-resistant upper limit according to the highest working temperature of the equipment (for example, HY610 with temperature -40 ℃ ~ 200 ℃ is selected for the oven to avoid high-temperature carbonization of silicone grease); Second, control the dosage. The volatilization of silicone grease at high temperature is related to the contact area. The thicker the coating is, the more volatile matter may be. The coating is applied according to the principle of "just fill the gap" to ensure heat dissipation and reduce volatilization. For example, the outdoor LED lamp board is coated with silicone grease, and the size of rice grains can be squeezed without excessive superposition.

In short, thermal conductive silicone grease is used in high temperature environment. As long as inferior products are avoided and silicone grease with high temperature resistance and low volatilization rate is selected, there is no need to worry about releasing harmful substances. Compliant silicone grease of brands such as Huaneng Zhiyan is used for a long time in ovens, microwave ovens and outdoor high-temperature equipment. It is safe and stable in heat dissipation without worrying about health and equipment corrosion. Remember: high-temperature silicone grease, first look at the certification and volatilization rate, refused to low-cost inferior, can be used at ease.