Reliable Ceramic Window Design for Electronic Devices

1992 ◽  
Vol 114 (3) ◽  
pp. 349-352
Author(s):  
Hsien-Yang Yeh
Keyword(s):  
Traveling Wave ◽  
Electronic Device ◽  
High Vacuum ◽  
Complex Nature ◽  
Circular Plates ◽  
Linear Elastic ◽  
Center Conductor ◽  
Elastic Fracture ◽  
Traveling Wave Tubes ◽  
Window Design

The effective operations of a high voltage vacuum electronic device, such as a traveling wave tube, depends on its ability to maintain high vacuum environments. However, during temperature tests, some tubes fail because of vacuum leaks through cracks in the ceramic window. It is believed that these leaks result from RF heating at the center conductor, which caused the ceramic to crack. To obtain a general understanding of the stress field in the window structure, a closed from analytical approach is imperative. However, due to the complex nature of the problem, only the first order engineering approximation is used in this preliminary study. The theory of linear elastic fracture mechanics and the existing solutions from elastic circular plates are useful for understanding the cause of ceramic window cracks. Some simple design references have also been developed for the design of reliable ceramic windows for traveling wave tubes.

Stress Analysis Applications to Service Failures of Traveling-Wave Tubes

1984 ◽  
Vol 106 (4) ◽  
pp. 533-537
Author(s):  
H.-Y. Yeh
Keyword(s):  
Stress Concentration ◽  
Traveling Wave ◽  
Elastic Stress ◽  
Electronic Device ◽  
Electrical Breakdown ◽  
Point Of View ◽  
Service Failures ◽  
Stress Concentration Factors ◽  
Traveling Wave Tubes ◽  
Element Technique

By utilizing the mathematical analogy between the electrostatic fields and the elastic stress field, the electrostatic stresses in high voltage electronic device such as Traveling Wave Tubes (TWT) can be obtained from finite element technique. A new point of view about the vacuum electrical breakdown from the theory of elastic stress concentration has been proposed. The elastic stress concentration factors may be used as a good reference figure for TWT design works.

Traveling wave tubes: a history of people and fates

2019 ◽  
Vol 190 (05) ◽  
pp. 543-556
Author(s):  
Dmitrii I. Trubetskov ◽  
Galina M. Vdovina
Keyword(s):  
Traveling Wave ◽  
History Of ◽  
Traveling Wave Tubes

Investigation of W-band Diverse-shaped Groove-loaded Folded Waveguide Traveling-wave Tubes

2013 ◽  
Vol 34 (7) ◽  
pp. 1760-1766 ◽  
Author(s):  
Bo Peng ◽  
Jun He ◽  
Ming-guang Huang ◽  
Bao-liang Hao ◽  
Pu-kun Liu
Keyword(s):  
Traveling Wave ◽  
Folded Waveguide ◽  
W Band ◽  
Traveling Wave Tubes

Fatigue Failure Analysis Using the Theory of Critical Distance

2011 ◽  
Vol 462-463 ◽  
pp. 663-667 ◽  
Author(s):  
Ruslizam Daud ◽  
Ahmad Kamal Ariffin ◽  
Shahrum Abdullah ◽  
Al Emran Ismail
Keyword(s):  
Stress Concentration ◽  
Fatigue Failure ◽  
Notch Root ◽  
High Stress ◽  
Critical Distance ◽  
Future Research ◽  
Element Analysis ◽  
Linear Elastic ◽  
The Finite Element Analysis ◽  
Elastic Fracture

This paper explores the initial potential of theory of critical distance (TCD) which offers essential fatigue failure prediction in engineering components. The intention is to find the most appropriate TCD approach for a case of multiple stress concentration features in future research. The TCD is based on critical distance from notch root and represents the extension of linear elastic fracture mechanics (LEFM) principles. The approach is allowing possibilities for fatigue limit prediction based on localized stress concentration, which are characterized by high stress gradients. Using the finite element analysis (FEA) results and some data from literature, TCD applications is illustrated by a case study on engineering components in different geometrical notch radius. Further applications of TCD to various kinds of engineering problems are discussed.

Development of High-Power Sub-THz Traveling-Wave Tubes with Multiple Sheet Electron Beams

2020 ◽  
Author(s):  
Nikita M. Ryskin ◽  
Gennadiy V. Torgashov ◽  
Roman A. Torgashov ◽  
Andrey G. Rozhnev ◽  
Vladimir N. Titov ◽  
...  
Keyword(s):  
High Power ◽  
Traveling Wave ◽  
Electron Beams ◽  
Traveling Wave Tubes

A Wideband High-Voltage Longitudinal Output Structure for Ka-Band Sheet Beam Traveling-Wave Tubes

2021 ◽  
Vol 69 (4) ◽  
pp. 2042-2047
Author(s):  
Xinjie Li ◽  
Jianxun Wang ◽  
Yixin Wan ◽  
Wei Jiang ◽  
Zewei Wu ◽  
...  
Keyword(s):  
High Voltage ◽  
Traveling Wave ◽  
Ka Band ◽  
Output Structure ◽  
Traveling Wave Tubes

Investigation on Stress and Strain Singularity in LEFM

2006 ◽  
Vol 306-308 ◽  
pp. 31-36
Author(s):  
Zheng Yang ◽  
Wanlin Guo ◽  
Quan Liang Liu
Keyword(s):  
High Stress ◽  
Crack Tip ◽  
Plane Stress State ◽  
Stress And Strain ◽  
Linear Elastic ◽  
Geometrical Nonlinear ◽  
Maximum Crack ◽  
Elastic Fracture ◽  
Plain Strain ◽  
Strain Singularity

Stress and strain singularity at crack-tip is the characteristic of Linear Elastic Fracture Mechanics (LEFM). However, the stress, strain and strain energy at crack-tip may be infinite promoting conflicts with linear elastic hypothesis. It is indicated that the geometrical nonlinear near the crack-tip should not be neglected for linear elastic materials. In fact, the crack-tip blunts under high stress and strain, and the singularity vanishes due to the deformation of crack surface when loading. The stress at crack-tip may still be very high even though the singularity vanishes. The low bound of maximum crack-tip stress is the modulus of elastic in plane stress state, while in plain strain state, it is greater than the modulus of elastic, and will increase with the Poisson’s ratio.

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