scholarly journals Thermal Analysis of Si/GaAs Bonding Wafers and Mitigation Strategies of the Bonding Stresses

2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Yuanying Qiu ◽  
Xun Qiu ◽  
Xianghu Guo ◽  
Dian Wang ◽  
Lijie Sun
Keyword(s):  
Finite Element Method ◽  
Thermal Stress ◽  
Stress Distribution ◽  
Wafer Bonding ◽  
Thermal Stresses ◽  
Annealing Process ◽  
Mitigation Strategies ◽  
Stress Theory ◽  
Effective Strategies ◽  
Thermal Stress Distribution

In order to effectively reduce the thermal stresses of Si/GaAs bonding wafers during their annealing process, first of all, based on E. Suhir’s bimaterial thermal stress theory, the thermal stresses in the wafer bonding interfaces are analyzed and the thermal stress distribution formulas are obtained. Then, the thermal stress distribution curves of Si/GaAs bonding interfaces are investigated by finite element method (FEM) and are compared with the results from E. Suhir’s bimaterial thermal stress theory. Finally, some effective strategies are proposed to reduce the thermal stresses in the bonding interfaces.

scholarly journals Mutual Influence of Geometric Parameters and Mechanical Properties on Thermal Stresses in Composite Laminated Plates with Rectangular Holes

Mathematics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 311
Author(s):  
Mohammad Hossein Bayati Chaleshtari ◽  
Mohammad Jafari ◽  
Hadi Khoramishad ◽  
Eduard-Marius Craciun
Keyword(s):  
Mechanical Properties ◽  
Heat Flux ◽  
Thermal Stress ◽  
Stress Distribution ◽  
Thermal Stresses ◽  
Mutual Influence ◽  
Geometric Parameters ◽  
Stacking Sequence ◽  
Rectangular Hole ◽  
Thermal Stress Distribution

In this research, the mutual influence of the mechanical properties and geometric parameters on thermal stress distribution in symmetric composite plates with a quasi-rectangular hole subjected to uniform heat flux is examined analytically using the complex variable technique. The analytical solution is obtained based on the thermo-elastic theory and the Lekhnitskii’s method. Furthermore, by employing a suitable mapping function, the solution of symmetric laminates containing a circular hole is extended to the quasi-rectangular hole. The effect of important parameters including the stacking sequence of laminates, the angular position, the bluntness, and the aspect ratio of the hole and the flux angle in the stacking sequence of [45/−45]s for composite materials are examined in relation to the thermal stress distribution. The thermal insulated state and Neumann boundary conditions at the hole edge are taken into account. It is found out that the hole rotation angles and heat flux angle play key roles in obtaining the optimum thermal stress distribution around the hole. The present analytical method can well investigate the interaction of effective parameters on symmetric multilayer composites under heat flux.

scholarly journals INFLUENCE OF THE MODEL SIZE IN THE NUMERICAL DETERMINATION OF THE AVERAGE THERMAL STRESSES IN AN MMC COMPOSITE

2011 ◽  
Vol 10 (1-2) ◽  
pp. 23
Author(s):  
C. A. de J. Miranda ◽  
R. M. P. Libardi ◽  
S. Marcelino ◽  
Z. M. de Boari
Keyword(s):  
Thermal Stress ◽  
Stress Distribution ◽  
Thermal Stresses ◽  
Metallic Matrix ◽  
Aluminum Matrix ◽  
High Strength ◽  
Plastic Behavior ◽  
Non Linear ◽  
Model Size ◽  
Thermal Stress Distribution

In previous works the authors discussed some issues related to a specific metallic matrix composites (MMC), the Aluminum matrix reinforced with SiC particles (Al+SiC) which has a metal matrix (powder) mixed with ceramic particles. These materials have some advantages when used as a structural material such as their high strength and good conformability. Their properties depend, among others, on the volumetric ratio, the  particles size and distribution besides the matrix microstructure itself. Some of them are obtained at elevated temperature what produces a thermal stress state in the material. The Al+SiC is one of the later. The powder mix is extruded at 600oC and it is used at 20oC. Several numerical analyses were performed considering the random distribution of the particles and a non-linear behavior in the aluminum matrix. The results showed strong influence of the aluminum elastic-plastic behavior in the composite thermal stress distribution due to its manufacturing process. However, one issue remained: the size of the model. It represents the central portion of a Al+SiC bar which is only about 10 times the size of a single particle (~10L). The present work investigates, always numerically, the influence of the model size on the thermal stress distribution. It considers 2 sets of non-linear analyses with random distributed particles: one with 20 models with size of 20L each one, the other set with another 20 models with size 40L. This approach allows a view of the results tendency compared with the 10L ones. As done before, the modeled volumetric ratio has a very tight range of values with its average very near to the value in an actual Al+SiC composite. It is showed that the first model size was already enough to get good results without sacrificing neither the computer nor the analyst time.

Finite Element Analysis of Thermal Stress Distribution in Planar SOFC

2019 ◽  
Vol 7 (1) ◽  
pp. 1977-1986 ◽  
Author(s):  
Chih-Kuang Lin ◽  
Tsung-Ting Chen ◽  
An-Shin Chen ◽  
Yau-Pin Chyou ◽  
Lieh-Kwang Chiang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Thermal Stress ◽  
Stress Distribution ◽  
Element Analysis ◽  
Thermal Stress Distribution

Surface thermal stress distribution and the influence factors of Sapphire/AlN/GaN epilayers

2016 ◽  
Vol 45 (10) ◽  
pp. 1021001
Author(s):  
陈 靖 Chen Jing ◽  
程宏昌 Cheng Hongchang ◽  
吴玲玲 Wu Lingling ◽  
冯 刘 Feng Liu ◽  
苗 壮 Miao Zhuang
Keyword(s):  
Thermal Stress ◽  
Stress Distribution ◽  
Influence Factors ◽  
Thermal Stress Distribution

scholarly journals The Numerical Modeling of Thermal Stress Distribution in Thermal Barrier Coatings

2017 ◽  
Vol 62 (3) ◽  
pp. 1433-1437
Author(s):  
A. Jasik
Keyword(s):  
Thermal Stress ◽  
Stress Distribution ◽  
Thermal Barrier Coatings ◽  
Bond Coat ◽  
Thermal Spraying ◽  
Ceramic Coatings ◽  
Thermal Barrier ◽  
Insulation Layer ◽  
Barrier Coatings ◽  
Thermal Stress Distribution

Abstract The paper presents the results of numerical calculations of temperature and thermal stress distribution in thermal barrier coatings deposited by thermal spraying process on the nickel based superalloy. An assumption was made to apply conventional zirconium oxide modified with yttrium oxide (8YSZ) and apply pyrochlore type material with formula La2Zr2O7. The bond coat was made of NiCoCrAlY. Analysis of the distribution of temperature and stresses in ceramic coatings of different thicknesses was performed in the function of bond-coat thickness and the type of ceramic insulation layer. It was revealed that the thickness of NiCrAlY bond-coat has not significant influence on the stress distribution, but there is relatively strong effect on temperature level. The most important factor influenced on stress distribution in TBC system is related with type and properties of ceramic insulation layer.

Sign in / Sign up

Export Citation Format

Share Document