scholarly journals Ultrasonic-Assisted Brazing of Titanium Joints Using Al-Si Based Fillers: Numerical and Experimental Process Design

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1686
Author(s):  
Abdulsalam Muhrat ◽  
Joaquim Barbosa
Keyword(s):  
Numerical Model ◽  
Process Design ◽  
Acoustic Pressure ◽  
Joint Interface ◽  
Compression Load ◽  
Experimental Part ◽  
Ultrasonic Assisted ◽  
Experimental Process ◽  
Si Content ◽  
Multiple Conditions

The ultrasonic-assisted brazing process was studied both numerically and experimentally. The ultrasonic brazing system was modeled by considering the actual brazing conditions. The numerical model showed the distribution of acoustic pressure within the filler and its variations according to the gap distance at different brazing temperatures. In the experimental part, brazing joints were studied and evaluated under multiple conditions and parameters. Although either the initial compression load or the ultrasonic vibration (USV) can initiate the interaction at the interface, the combined effect of both helped to produce joints of a higher quality with a relatively short brazing time, which can be further optimized in terms of their mechanical strength. The effect of the Si content on the joint interface, and the effect of the brazing conditions on the microstructures were studied and discussed.

Effect of micro in-plane fiber waviness on compressive properties of unidirectional fabric composites

2017 ◽  
Vol 52 (15) ◽  
pp. 2065-2074 ◽  
Author(s):  
Bo Wang ◽  
Nobuhide Uda ◽  
Kousei Ono ◽  
Hiroto Nagai
Keyword(s):  
Compressive Strength ◽  
Numerical Model ◽  
Tensile Stress ◽  
Compressive Modulus ◽  
Two Dimensional ◽  
Compressive Properties ◽  
Fiber Waviness ◽  
Experimental Part ◽  
Fabric Composites ◽  
Vartm Process

In this paper, a combination of experimentation and analysis is used to study the effect of micro in-plane fiber waviness on the compressive properties of unidirectional fabric composites. The experimental part includes a measurement of the micro in-plane fiber waviness in two types of unidirectional fabrics, manufacturing composites with each unidirectional fabric via VaRTM process and tests for establishing the compressive modulus and strengths of the composites. The compressive strengths were confirmed to be affected by the micro in-plane fiber waviness, but the compressive modulus was not. Furthermore, a two-dimensional numerical model is proposed to explain our experimental results. The numerical results indicate that the tensile stress (owing to the micro in-plane fiber waviness) and compressive stress along the weft and warp directions, respectively, of the composite lead to reductions in the compressive strength.

scholarly journals Ultrasonic-Assisted Brazing of Titanium Joints Using Modified Al-Si-Cu Based Fillers: Brazing at Liquid—Semisolid States under Load

Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1968
Author(s):  
Abdulsalam Muhrat ◽  
Joaquim Barbosa
Keyword(s):  
Ultrasonic Vibration ◽  
Solid Fraction ◽  
Intermetallic Layer ◽  
Compression Load ◽  
Average Value ◽  
Intermetallic Particles ◽  
High Solid Fraction ◽  
Ultrasonic Assisted ◽  
Successful Technique ◽  
Liquid States

Brazing joints of Ti/Ti under ultrasonic vibration (USV) and compression load were investigated using optimized and modified filler alloys of Al-Si-Cu-(Ni)-(Sr) group prepared in the lab. Preliminary trails at semisolid to liquid states were conducted using the ready Al-Si-Cu-(Mg) alloy as a filler, then the brazing cycle was redesigned and enhanced according to the microstructural observations of the produced joints. USV assisted brazing at semisolid state of low solid fraction was able to produce joints with round silicon morphology and granular , while at high solid fraction, USV was only able to affect the silicon and intermetallic particles. Applying a compression load after ultrasonic vibration, at a designed solid fraction, was proved to be a successful technique for improving the quality of the joints by reducing the porosity, enhancing the soundness of the joint, and the diffusion at the interface. Based on alloy composition and the improved brazing cycle, joints of thin intermetallic layer and high shear strength (of 93 MPa average value) were achieved. The microstructures and the mechanical behavior were discussed based on the filler compositions and brazing parameters.

Verification of Numerical Roll Forming Loads with the Aid of Measurement Equipment

2014 ◽  
Vol 939 ◽  
pp. 373-380 ◽  
Author(s):  
Peter Groche ◽  
Christian Mueller ◽  
Lars Baeumer
Keyword(s):  
Numerical Model ◽  
Process Design ◽  
Mass Production ◽  
Roll Forming ◽  
Measurement Equipment ◽  
Forming Process ◽  
Forming Simulation ◽  
Roll Forming Process

Roll forming is an important forming process for profile manufacturing in mass production. The design of the process has an important influence on the quality of the products. Therefore, the knowledge of the occurring loads during the roll forming process, e.g. forces and pressures, is essential for the process design. However, the experimental determination of the occurring contact normal pressures in roll forming processes poses a challenge. Finite element simulations offer the potential to approximate contact normal loads and thus, enable a better process design. Nevertheless, due to simplifications of the numerical model, a realistic and reliable output of loads in roll forming is not possible. An enhanced numerical model could provide more valuable information. This paper will demonstrate the reproduction of realistic contact normal pressures and load forces in a roll forming simulation. To verify the numerical values, they will be compared to data gained by experiments.

scholarly journals Design Optimization With an Uncertain Vibroacoustic Model

2008 ◽  
Vol 130 (2) ◽  
Author(s):  
E. Capiez-Lernout ◽  
C. Soize
Keyword(s):  
Numerical Model ◽  
Design Optimization ◽  
Optimization Problem ◽  
Acoustic Pressure ◽  
Design Parameters ◽  
Internal Cavity ◽  
Admissible Set ◽  
Acoustic Source ◽  
Model Uncertainties ◽  
Numerical Application

This paper deals with the design optimization problem of a structural-acoustic system in the presence of uncertainties. The uncertain vibroacoustic numerical model is constructed by using a recent nonparametric probabilistic model, which takes into account model uncertainties and data uncertainties. The formulation of the design optimization problem includes the effect of uncertainties and consists in minimizing a cost function with respect to an admissible set of design parameters. The numerical application consists in designing an uncertain master structure in order to minimize the acoustic pressure in a coupled internal cavity, which is assumed to be deterministic and excited by an acoustic source. The results of the design optimization problem, solved with and without the uncertain numerical model, show significant differences.

scholarly journals The Experimental Process Design of Artificial Lightweight Aggregates Using an Orthogonal Array Table and Analysis by Machine Learning

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5570
Author(s):  
Young Min Wie ◽  
Ki Gang Lee ◽  
Kang Hyuck Lee ◽  
Taehoon Ko ◽  
Kang Hoon Lee
Keyword(s):  
Machine Learning ◽  
Process Design ◽  
Orthogonal Array ◽  
Predictive Performance ◽  
Machine Learning Techniques ◽  
Support Vector ◽  
Lightweight Aggregates ◽  
Learning Techniques ◽  
Experimental Process ◽  
Sintering Processes

The purpose of this study is to experimentally design the drying, calcination, and sintering processes of artificial lightweight aggregates through the orthogonal array, to expand the data using the results, and to model the manufacturing process of lightweight aggregates through machine-learning techniques. The experimental design of the process consisted of L18(3661), which means that 36 × 61 data can be obtained in 18 experiments using an orthogonal array design. After the experiment, the data were expanded to 486 instances and trained by several machine-learning techniques such as linear regression, random forest, and support vector regression (SVR). We evaluated the predictive performance of machine-learning models by comparing predicted and actual values. As a result, the SVR showed the best performance for predicting measured values. This model also worked well for predictions of untested cases.

Implementation of a Numerical Model to Define a Bending Manufacturing Process

2016 ◽  
Vol 853 ◽  
pp. 36-41 ◽  
Author(s):  
Norberto Feito ◽  
Antonio Díaz-Álvarez ◽  
José Luis Cantero ◽  
Marcos Rodríguez Millán ◽  
Jorge López-Puente ◽  
...  
Keyword(s):  
Numerical Model ◽  
Process Design ◽  
Manufacturing Process ◽  
Process Modelling ◽  
Industrial Engineering ◽  
Computer Integrated Manufacturing ◽  
Forming Process ◽  
Integrated Manufacturing ◽  
New Learning ◽  
Computer Aided

The main goal of this paper is to show the new learning methodologies in techniques of forming process modelling in the context of Master in Industrial Engineering. In this context, Computer integrated manufacturing (CIM) has been established as a valuable tool for manufacturing process. The methodology developed in this work combines the process design, the usefulness workpiece and the computer aided (CAM).

Reliability Analysis of ACF Interconnection Assembly Process Using FEM

2005 ◽  
Vol 297-300 ◽  
pp. 1828-1833
Author(s):  
Hideo Koguchi ◽  
Wisessint Attaporn ◽  
Kazuto Nishida
Keyword(s):  
Stress Distribution ◽  
Reliability Analysis ◽  
Mechanical Loading ◽  
Flip Chip ◽  
Elastic Recovery ◽  
Joint Interface ◽  
Assembly Process ◽  
Anisotropic Conductive Film ◽  
Conductive Film ◽  
Experimental Process

Anisotropic conductive film (ACF) is commonly used as underfill for flip chip assembly. The present study focuses on elastic recovery and stress distribution along the interfaces of particle-pads and underfill-pads associated with heat or a mechanical loading. In the same manner as the experimental process for ACF assemblies, ACF interconnection is simulated using FEM. Firstly, the properties of the nickel were determined by fitting FEM to the experimental results. After that, the nickel properties are used for ACF interconnection analysis. We found that delamination may also occur at a three-joint interface of a particle, a pad and an underfill at the lowest temperature during a heat cycle.

Linear Elastic Analysis of Bovine Cortical Bone under Compression Loading

2013 ◽  
Vol 845 ◽  
pp. 324-329 ◽  
Author(s):  
Theng Pin Ng ◽  
Seyed Saeid Rahimian Koloor ◽  
Joy Rizki Pangestu Djuansjah ◽  
Mohammed Rafiq Abdul Kadir
Keyword(s):  
Cortical Bone ◽  
Bone Structure ◽  
Orthopedic Implants ◽  
Computational Method ◽  
Elastic Response ◽  
Mechanical Behaviors ◽  
Compression Load ◽  
Linear Elastic ◽  
Maximum Stiffness ◽  
Experimental Process

Linear elastic response of the bovine cortical bone has been examined under compression load. Experimental and computational methods were used to observe and predict the response of cortical bone. In computational method, two mechanical behaviors of isotropic and orthotropic were considered to simulate the cortical bone deformation. In experimental process, the specimens were designed to show maximum stiffness and strength by specifying osteon direction along loading axis during tests. The tests were controlled by displacement rate of 0.5 mm/minute and the overall stiffness responses of the structures were recorded to extract mechanical properties and also for validation aims. Finite Element Method (FEM) was used to model the linear response of the structure by using ABAQUS6.9EF. The FE results using orthotropic definition shows a good correlation with experimental data. A discussion was given based on overall stiffness and effective stress variation for both mechanical behaviors. In order to design the optimal implant structure, the presented study was proposed for prediction of bone structure deformation that attached to the orthopedic implants.

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