Affordable Cost Of Al-Si Controlled Expansion Alloys

Affordable Cost Of Al-Si Controlled Expansion Alloys
Chat Now
Product Details

Al-Si controlled expansion alloys possess the lower weight-adjustable coefficient of thermal expansion( CTE)-high thermal conductivity features.Aluminum Silicon alloys are lightweight, high thermal conductivity alloys that are increasingly being used for RF & microwave packages, electro-optical housing, power device base plates and other critical heat sinking applications. The manufacture of these packages requires the Al-Si body containing the electronics to be hermetic sealed using Aluminum 4047 lids. The heat sensitivity of the weld requires the use of a pulsed laser, however welding alloys  with a silicon content over 27% becomes increasingly problematic due to cracking of the Al-Si alloy. This is due to the weakness of the Al-Si alloy under the solidification forces of the weld. The thermal performance advantage of the higher silicon content alloys has great potential for significantly improving power handling of the packages. Therefore, a welding process was developed using pulse shaping and a minimized average power approach that eliminated cracking in alloys with up to 40% silicon.


These controlled expansion alloys are offered in a range of weight proportions of silicon and aluminum from 70Si-30Al to 27Si-73Al, with CTE’s 7 to 17 ppm/°C respectively. The specific applications of these alloys in summarized below table. Aside from tailoring the CTE, the key advantages these alloys over materials such as kovar and Cu-W are reduced weight, high stiffness and ease of manufacture.



Baienwei

AlSi Alloy’s

Composition

 

CTE

25℃ (ppm)

 

 

Baienwei

AlSi Alloy’s

Grades

 

 

Applications

 

 Al-27%Si

 

 17

 

  AlSi27 alloy

Commonly electronic packaging;Circuit boardstiffener;Heat sink/spreader for avionic/telecommunications.

 

 Al-42%Si

 

 13.5

 

 AlSi42 alloy

Laser-mirror;Electro-optia housing;optical devices;

 

 Al-50%Si

 

 11.5

 

 AlSi50 alloy

High-power electronic packaging;housing;radar packages

 

 Si-40%Al

 

 10

 

 AlSi60 alloy

Power device and laser packages

 

 Si-30%Al

 

 7.5

 

 AlSi70 alloy

RF & microwave packages;High-brightness(HB)LED;Electro-optical  housing;High-power laser substrate.





Feedback