The introduction of Vapor Chamber:
Vapor chamber is a vacuum chamber with microstructure on its inner wall. When heat is conducted from the heat source to the evaporation area, the working gadgets in the chamber will start to produce liquid phase evaporation in a low vacuum environment. At this time, the working gadgets absorbs heat energy and expands rapidly, and the working gadgets in gas phase will fill the whole chamber quickly. When the working gadgets in gas phase comes into contact with a relatively cold area, condensation will occur. The accumulated heat during evaporation will be released by condensation, and the condensed liquid phase working medium will return to the evaporation heat source by capillary phenomenon of microstructure. Because the microstructure can generate capillary force when the working gadgets evaporates, the operation of the vapor chamber can not be affected by gravity.
The working principle：
The principle and theoretical framework of vapor chamber and heat pipe are the same, only the heat conduction mode is different. The heat conduction mode of heat pipe is one facial panel and linear, while the heat conduction mode of vapor chamber is two facial panel and planar.
The Chamber material：
C1100 toughening copper smelting working gadgets Water (purified and degassed) microstructure Single-layer or multi-layer copper nets are connected with each other by diffusion bonding and tightly bonded with the cavity, which has the same effect as copper powder sintering. Microstructure characteristics of bonded copper mesh:
1. The pore diameter is about 50μm to 100μm.
2. Microstructures with different aperture sizes in the upper and lower layers can be fabricated, which will provide micro-structure lifting efficiency.
3. Microstructures with multiple different aperture areas on the same plane can be fabricated
4. Use characteristics Different microstructures can be made in the evaporation zone and condensation zone to meet the needs of products. There are two basic combinations in the evaporation zone and nine basic combinations in the condensation zone, which can be used together as needed.
Shape and size：
The maximum size is 400mm x 400mm, and there is no shape restriction. Thickness 3.5mm to 4.2mm, the thinnest can be as thin as 3 mm. Support and pressure resistance There are copper columns connecting the upper and lower covers inside, which can withstand up to 3.0kg/ cm2 (about 130 C internal pressure of the environment) perforation Vapor chamber can be perforated. Flatness According to different cavity wall thickness and copper column design, the contact surface of heat source can reach 50μm and the other parts can reach 100μm. The thickness of copper sheet and the number of copper columns will affect the efficiency and flatness of vapor chamber Post-processing process The fins can be welded after the vapor chamber test is completed, which will not affect the performance of the vapor chamber, and the product quality is more guaranteed and the processing is more flexible.
Vapor chamber production technology is based on product efficiency and quality requirements, with the consideration of mass production feasibility and cost. The developed mass production technology has the following technical characteristics. Combined copper mesh microstructure According to the characteristics of evaporation zone and condensation zone, copper mesh microstructures with different pore sizes can be produced in vapor chamber. Microstructure with different apertures in upper and lower layers can be produced in the same layer of microstructure, which is difficult to achieve by sintering microstructure.
High-order diffusion bonding technology can complete the mutual bonding of two metals without any joint. After bonding, the two metals will be combined into one. Our company uses this technology to complete the bonding around the vapor chamber, between microstructures and copper pillars. After bonding, the leakage rate is lower than 9 x 10-10 mbar/sec, and the tensile force can reach 3kgs/cm2, which fully meets the demand of vapor chamber products without any environmental problems. Vacuum degassing water injection It can control the internal cleanliness and vacuum degree of vapor chamber, and ensure the stability of product performance and quality. Vacuum high frequency and high frequency welding When used in filling microtube welding, high-frequency heating has the characteristics of short heating time and concentrated temperature range, which can effectively and quickly complete the Brazing of filling tubes, and is carried out in a vacuum environment to prevent the oxidation inside the cavity during welding. leak hunting To ensure the airtightness of the product, two kinds of leak detection are adopted:
(1) positive pressure leak detection
(2) negative pressure leak detection (helium leak detection). Flexible and reliable product design Vapor chamber of various shapes and thicknesses can be designed according to performance and cost requirements, and reliable and detailed product data can be quickly provided by professional laboratory testing equipment, so as to accelerate the timeliness of customer product development.
Vapor chamber has been our strategic project during the heat sinks or just solid VC in the phone application, we believe that technology is changing from every time that you need to input some new technique so that make sure the improvement of your product, especially the thermal cooling products like heat sinks. Please contact us for more thermal solution and we can have a nice talking about it. Thanks for reading!