Microwave welding alumina and alumina
Alumina ceramic oxide ceramics in the highest mechanical strength , hardness, good electrical insulation , high-frequency loss, thermal conductivity is large and dense vacuum , can more fully meet the requirements of electric vacuum ceramic , except for the electric vacuum the device can also be used outside the IC substrate , thyristors and solid circuit shell. Currently the most widely used in the welding of the dielectric material is about 95% of alumina containing 95 porcelain, alumina containing about 99% and 99 ceramic and transparent alumina ceramic is generally used for performance of some of the special requirements of the occasion .
 In 1985 , T. K. Meek took the lead with a 700W power and other domestic microwave oven for 2 aluminum foil between the glass sealing , sealing temperature is 700 ℃ a 800 degrees ; , time 99min, 1988年, D.Palath repeat the above work by the difference is that the microwave power is only 75W, sealing time was 10min.
H. Fukushima et 6GHz frequency with 3KW power and single-mode microwave cavity alumina rod for welding . Microwave welding of 92% purity alumina rod when welding and bending strength of the relationship between temperature , where the welding time was 3min, welding pressure of 0.6MPa.
Alumina rod with the bending strength of the welding joint the increase of the temperature , when the soldering temperature exceeds 1750 ℃ ​​, the alumina rod joint average bending strength is 420MPa, this result has been achieved resistant alumina substrate bending strength values ​​and the experimental results also show that the welded joint of microwave hardness value is greater than the hardness of the substrate is higher by 20%.
  X.D.Yu other successful while using microwave sintering and welding the two alumina wafer , they believe , microwave sintering and welding both ceramic materials technology also can be used for the production of multilayer capacitors.
  S.Al a Assafi such as aluminum hydroxide gel adhesive under microwave irradiation welding alumina ceramics. Experimental results show that when the soldering temperature to 1650 ℃ river , the microwave bending strength of welded joints value has reached the base 93% of the flexural strength . As an adhesive agent, aluminum hydroxide gel , when the temperature is higher than
1300 ℃ , the decomposition of a one A1203
Due to decomposition products . Alumina : and welding consistent composition of the matrix . A12O3 fill the gap weld interface , better compatibility between the materials , thereby improving the mechanical properties of the material .
 Cai Jiedeng single rectangular cavity with TE1On in 1300 `, 1400 ℃ temperature on A12O3-A12 horses were soldered directly . That , at 1300 ℃ welding, despite prolonged heat, welding effect is not obvious, visible seam ; insulation at 1400 ℃ 20min, and achieved good welding effect , when the weld has disappeared .