Residual Stress Analysis for Engine Block by the Grooving Method

2015 ◽  
Vol 750 ◽  
pp. 236-243
Author(s):  
Chong Guo ◽  
Qing Hua Lu ◽  
Pei Lei Zhang ◽  
Bi Rong Peng ◽  
Xiao Feng He
Keyword(s):  
Residual Stress ◽  
Automobile Industry ◽  
Materials Science ◽  
Stress Test ◽  
Welding Process ◽  
Internal Surface ◽  
Industrial Applications ◽  
Engine Block ◽  
Wide Range ◽  
Cutting Sequence

The study of residual stress in engine block has the potential to provide the necessary infrastructure for a wide range of scientific and technological developments concerning the automobile industry. Such study can act as centre of excellence for scientific studies in the field of materials science and machinery as well as for industrial applications. The basic principle of measuring residual stress with grooving method and the main measuring steps were introduced in this paper. Groove cutting in the internal surface of engine block surrounds a given area in which the remaining stress is released, and then the strain results are recorded through strain gauge. The residual stress test data were compared at different positions of each engine block. It is found that engine blocks A and D on the sides of engine develop higher residual stresses than blocks B and C in the centre of engine. The stresses can be higher than 200MPa in tension in engine block A, depending on the geometry, size, microstructure, subsequent welding process, and cutting sequence. In addition, residual stress at the bottom of engine is higher than that at the top because of the structure of the engine. The residual stress is also calculated by numerical modeling method from which it shown that the condition is commendably fit the results which the distribution of stress.

Zeolates: A Coordination Chemistry View of Metal-Ligand Bonding in Intrazeolite MOCVD Type Precursors and Semiconductor Nanoclusters

1992 ◽  
Vol 277 ◽  
Author(s):  
Geoffrey A. Ozin ◽  
Carol L. Bowes ◽  
Mark R. Steele
Keyword(s):  
Self Assembly ◽  
Materials Science ◽  
Zeolite Y ◽  
Chemical Vapour ◽  
Internal Surface ◽  
Building Blocks ◽  
Structural Features ◽  
Organic Chemical ◽  
Wide Range ◽  
Shape Selective

ABSTRACTVarious MOCVD (metal-organic chemical vapour deposition) type precursors and their self-assembled semiconductor nanocluster products [1] have been investigated in zeolite Y hosts. From analysis of in situ observations (FTIR, UV-vis reflectance, Mössbauer, MAS-NMR) of the reaction sequences and structural features of the precursors and products (EXAFS and Rietveld refinement of powder XRD data) the zeolite is viewed as providing a macrospheroidal, multidendate coordination environment towards encapsulated guests. By thinking about the α- and β-cages of the zeolite Y host effectively as a zeolate ligand composed of interconnected aluminosilicate “crown ether-like” building blocks, the materials chemist is able to better understand and exploit the reactivity and coordination properties of the zeolite internal surface for the anchoring and self-assembly of a wide range of encapsulated guests. This approach helps with the design of synthetic strategies for creating novel guest-host inclusion compounds having possible applications in areas of materials science such as nonlinear optics, quantum electronics, and size/shape selective catalysis.

scholarly journals Finite element modelling of multi-pass fusion welding with application to complex geometries

2007 ◽  
Vol 221 (4) ◽  
pp. 225-234 ◽  
Author(s):  
W Jiang ◽  
K Yahiaoui
Keyword(s):  
Residual Stress ◽  
Three Dimensional ◽  
Welding Process ◽  
Industrial Applications ◽  
Fusion Welding ◽  
Modelling Technique ◽  
Welding Parameters ◽  
Complex Geometries ◽  
Stress Distributions ◽  
Element Removal

The current paper presents recently completed work in the development of advanced multi-pass weld modelling procedures, with the ultimate objective of predicting weld residual stress distributions in thick-walled complex geometries. The modelling technique was first developed using simple three-dimensional geometries, for which experimental data was available for validation purposes. All the non-linearities associated with welding, including geometry, material, and boundary non-linearities, as well as heat source movement were taken into account. The element removal/reactivate technique was employed to simulate the deposition of filler material. Combined with a newly developed meshing technique, the model was then applied to predict residual stress distributions for a relatively thick stainless steel piping branch junction. Finally, a parametric study was conducted to assess the effects of various manufacture-related welding parameters on the final residual stress fields. The interpass temperature and cooling rate were found to be the two most sensitive parameters affecting resultant residual stresses. The residual stress profiles can be optimized relatively easily by adjusting these parameters. This research demonstrated that the developed modelling technique has potential in multi-pass welding process optimization and wide industrial applications including weld repairs.

Interfacial Microstructure and Strength of Friction Welding of Steel Tube to Aluminium Tube Plate Using an External Tool

2011 ◽  
Vol 383-390 ◽  
pp. 877-881 ◽  
Author(s):  
S. Muthukumaran ◽  
C. Vijaya Kumar ◽  
S. Senthil Kumaran ◽  
A. Pradeep
Keyword(s):  
Friction Welding ◽  
Thermal Power ◽  
Welding Process ◽  
Dissimilar Materials ◽  
Industrial Applications ◽  
Interfacial Microstructure ◽  
Steel Tube ◽  
Tube Plate ◽  
Wide Range ◽  
Interface Hardness

Joining of dissimilar materials is of increasing interest for a wide range of industrial applications like nuclear, thermal power. The automotive industry, in particular, views dissimilar materials joining as a gateway for the implementation of lightweight materials. Friction welding of tube to tube plate using an external tool is an innovative friction welding process and is capable of producing high quality leak proof weld joints. In the present study, friction welding of steel tube to commercial aluminum tube plate using an external tool with and without tube projection have been performed. The joints were evaluated by mechanical testing and metallurgical analysis. The results of bonding interface hardness and joint strength reveal that steel tube with projection are better than the steel tube without projection.

The Aqueous Chemistry of Oxides

2016 ◽  
Author(s):  
Bruce C. Bunker ◽  
William H. Casey
Keyword(s):  
Materials Science ◽  
Aqueous Media ◽  
Chemical Properties ◽  
Industrial Applications ◽  
Oxide Materials ◽  
Aqueous Chemistry ◽  
Wide Range ◽  
Aqueous Environments ◽  
Critical Issues ◽  
Physical And Chemical

The Aqueous Chemistry of Oxides is a single-volume text that encapsulates all of the critical issues associated with how oxide materials interact with aqueous solutions. It serves as a central reference for academics working with oxides in the contexts of geology, various types of inorganic chemistry, and materials science. The text also has utility for professionals working with industrial applications in which oxides are either prepared or must perform in aqueous environments. The volume is organized into five key sections. Part One features two introductory chapters, intended to introduce the mutual interests of engineers, chemists, geologists, and industrial scientists in the physical and chemical properties of oxide materials. Part Two provides the essential and fundamental principles that are critical to understanding most of the major reactions between water and oxides. Part Three deals with the synthesis of oxide materials in aqueous media. Part Four deals with oxide-water reactions and their environmental and technological impacts, and Part Five is devoted to other types of relevant reactions. The Aqueous Chemistry of Oxides is the first book that provides a comprehensive summary of all of the critical reactions between oxides and water in a single volume. As such, it ties together a wide range of existing books and literature into a central location that provides a key reference for understanding and accessing a broad range of more specialized topics. The book contain over 300 figures and tables.

Growth Structures and Phase Formation in Industrially Room-Temperature Pulsed Laser Deposited FCC Ti-Based Nitride Coatings

2006 ◽  
Vol 513 ◽  
pp. 85-104 ◽  
Author(s):  
Juergen Lackner
Keyword(s):  
Room Temperature ◽  
Materials Science ◽  
Lattice Structure ◽  
Pulsed Laser ◽  
Industrial Applications ◽  
High Rate ◽  
Surface Finishing ◽  
Face Centered Cubic ◽  
Coating Materials ◽  
Wide Range

The current work focuses on the materials science aspects of the growth phenomena of titanium-based coatings TiN, (Ti,Al)N and (Ti,Al)(C,N) with face-centered cubic lattice structure, deposited by the industrially-styled Pulsed Laser Deposition (PLD) technique at room temperature. hese coating materials are widely spread in mechanical, tribological and decorative applications due to their exceptional physical and chemical properties. Recently, the trend of using temperaturesensitive materials like polymers and tool steels of the highest hardness demands new lowtemperature coating techniques for protective surface finishing as well as for functionalization of the surfaces. These titanium-based compounds can fulfill a wide range of these demands, but up to now there is a lack of industrially designed vacuum coating techniques operating at temperatures lower than 50 °C necessary for these materials. The PLD process is known as one of the most promising candidates for such coating demands. But up to now PLD is only a well-established laboratory coating technology and has not become a standard industrial coating technique despite its outstanding process features. The missing of PLD coating systems, which fulfill the requirements for industrial applications like high-rate deposition and adequate sizes of deposition chambers, is considered as one of the main obstacles for a breakthrough of the PLD technique. To overcome this problem an industrially designed PLD coating system has been developed and built at the Laser Center Leoben of JOANNEUM Research Forschungsgesellschaft mbH.

Application of 3D Finite Element Modelling to Repair Weld Simulation in Industrial Applications

2002 ◽  
Author(s):  
George Vinas ◽  
Tamba Dauda ◽  
Nicola Moyes ◽  
Alan Laird
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Residual Stresses ◽  
Measurement Techniques ◽  
Fem Simulation ◽  
Welding Process ◽  
Industrial Applications ◽  
Welding Residual Stress ◽  
Experimental Techniques ◽  
Residual Stress Field

The Finite Element Method (FEM) has been implemented in 3D to predict welding residual stresses in repair welds. The analysis has been used to achieve more accurate residual stress predictions for the weld at the cost of long computation times. The use of this CPU intensive approach has been facilitated by the advent of ever-faster computer processors being made more accessible to the engineering community. The same technique has also been used with coarser meshes involving simplified welding sequences where a number of weld passes are “lumped” together to reduce the simulation time. The authors argue that this latter approach can be very useful in predicting the more global component response — in cases where 2D model symmetries are not applicable — and for rapid identification of problem areas where finer simulations would be prohibitive. The authors show an example of a residual stress prediction for a letterbox repair obtained using the FEM. Good agreement between this prediction and experimental measurements is shown. The FEM simulation technique has been used to predict residual stress formation during the welding process and subsequent service loading of the component. This analysis shows the residual stress field relaxation following “shakedown”. The component under service conditions is subjected to pressure loading and a small amount of bending stress. Based on recent residual stress experimental programmes conducted at Mitsui Babcock Energy Limited (MBEL), the authors provide a brief discussion on the ways in which various experimental techniques have been used to verify welding residual stress predictions from FE. The authors argue that just as there has been an interest in the field to measure residual stresses in the highly stressed regions of a weld, it is equally important to measure stresses in areas of relatively low stress to confirm that stresses do indeed die out away from welds. It is in the latter case where some experimental techniques cannot perform as well as other simple, well proven, strain measurement techniques.

scholarly journals Temperature Field and Residual Stress of Butt Welding for IN182 Plate

2018 ◽  
Vol 7 (4.10) ◽  
pp. 95
Author(s):  
Harinadh Vemanaboina ◽  
G. Janardhana Raju ◽  
Bura Sreenivas
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
Structural Changes ◽  
Welding Process ◽  
Industrial Applications ◽  
Butt Joint ◽  
Nonlinear Phenomenon ◽  
Element Analysis ◽  
Butt Welding ◽  
Effective Selection

The welding process is a nonlinear phenomenon in nature which leads to deformation and residual stresses in weldments. To overcome the structural changes in the weldments the computational packages can be effectively used for analyzing the changes in its life. Inconel superalloys have excellent mechanical properties and are used in the industrial applications. The present simulation is carried out for single pass butt-joint. Simulation studies are used for effective selection of process parameters for improving mechanical properties in the weld structures. In this work, coupled thermo-mechanical simulation process was carried out for predicting the temperatures, distortion and residual stress distribution in the weldments using Finite element analysis at the transverse direction on the welded surface.  

Three Dimensional Weld Residual Stress Simulations of Piping Butt Welds: Influence of Boundary Conditions and Start/Stop Positions on Axisymmetry

2016 ◽  
Author(s):  
Etienne Bonnaud ◽  
Jens Gunnars
Keyword(s):  
Residual Stress ◽  
Boundary Conditions ◽  
Structural Integrity ◽  
Three Dimensional ◽  
Welding Process ◽  
Internal Surface ◽  
Critical Crack ◽  
Butt Welds ◽  
Mechanical Restraint ◽  
Weld Residual Stress

Weld residual stress simulations have become an essential tool in structural integrity assessments. In piping, two dimensional axisymmetric simulations generally give good estimations of residual stresses but clearly cannot capture the three dimensional nature of the welding process: the start/stop effects and the constant change in mechanical restraint during a weld pass. In this study, three dimensional welding simulations have been carried out for piping butt welds, first on a dissimilar metal weld in a thin-walled pipe and second on a narrow gap weld in a thicker stainless steel pipe. The effects of mechanical boundary conditions and start/stop positions have been investigated and stress fields are shown to markedly deviate from axisymmetry. As an illustration, a fracture mechanical analysis of a partial internal surface crack reveals noticeable changes in critical crack sizes.

The Change of Residual Stress with Two-Wire Spacing of Twin-Wire Submerged Arc Welding

2012 ◽  
Vol 462 ◽  
pp. 154-159
Author(s):  
Xiu Zhi Yang ◽  
Wan Jing Ding ◽  
Jin Yu Jiang ◽  
Xin Hua Xiao
Keyword(s):  
Numerical Simulation ◽  
Residual Stress ◽  
Single Channel ◽  
Stress Test ◽  
Welding Process ◽  
Welding Residual Stress ◽  
Residual Stress Field ◽  
Finite Element Software ◽  
Wire Saw ◽  
The Impact

Finite element software MSC.MARC was used to analyze the residual stress of high-strength low-alloy steel suffered twin-wire SAW. The numerical simulation of the residual stress field with different twin-wire spacing was conducted. The residual stress test results under twin-wire SAW at twin-wire of 50 mm welding were compared to the simulation results, which verified the numerical simulation. The results showed that in the single-channel and twin-wire welding, the largest welding residual stress of the joints is located near the weld toe. At certain wire distances (20-100 mm) in the twin-wire welding process, increasing distance only minimally reduces welding residual stress. Thus, the effects of residual stress on two-wire spacing have been neglected in studies on the twin-wire welding process,More studies should focus on the impact of the performance and forming of the weld joint.

Substituent Effects on the Thermal Decomposition of Phosphate Esters on Ferrous Surfaces

2019 ◽  
Author(s):  
James Ewen ◽  
Carlos Ayestaran Latorre ◽  
Arash Khajeh ◽  
Joshua Moore ◽  
Joseph Remias ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Film Formation ◽  
Substituent Effects ◽  
Vapour Phase ◽  
Industrial Applications ◽  
Phosphate Esters ◽  
Antiwear Additives ◽  
Formation Mechanisms ◽  
Phosphate Ester ◽  
Wide Range

<p>Phosphate esters have a wide range of industrial applications, for example in tribology where they are used as vapour phase lubricants and antiwear additives. To rationally design phosphate esters with improved tribological performance, an atomic-level understanding of their film formation mechanisms is required. One important aspect is the thermal decomposition of phosphate esters on steel surfaces, since this initiates film formation. In this study, ReaxFF molecular dynamics simulations are used to study the thermal decomposition of phosphate esters with different substituents on several ferrous surfaces. On Fe<sub>3</sub>O<sub>4</sub>(001) and α-Fe(110), chemisorption interactions between the phosphate esters and the surfaces occur even at room temperature, and the number of molecule-surface bonds increases as the temperature is increased from 300 to 1000 K. Conversely, on hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>, most of the molecules are physisorbed, even at high temperature. Thermal decomposition rates were much higher on Fe<sub>3</sub>O<sub>4</sub>(001) and particularly α-Fe(110) compared to hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>. This suggests that water passivates ferrous surfaces and inhibits phosphate ester chemisorption, decomposition, and ultimately film formation. On Fe<sub>3</sub>O<sub>4</sub>(001), thermal decomposition proceeds mainly through C-O cleavage (to form surface alkyl and aryl groups) and C-H cleavage (to form surface hydroxyls). The onset temperature for C-O cleavage on Fe<sub>3</sub>O<sub>4</sub>(001) increases in the order: tertiary alkyl < secondary alkyl < primary linear alkyl ≈ primary branched alkyl < aryl. This order is in agreement with experimental observations for the thermal stability of antiwear additives with similar substituents. The results highlight surface and substituent effects on the thermal decomposition of phosphate esters which should be helpful for the design of new molecules with improved performance.</p>

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