Finite Element Analysis of Thermal Stress and Thermal Deformation in Typical Part during SLM

Selective laser melting (SLM) constitutes an additive manufacturing (AM) method. Many issues such as thermal strain and macro-thermal deformation, which are caused by the thermal stress of different process parameters, are not clear. In this paper, an efficient and fast manufacturing simulation method was researched based on a moving heat source model and an elastoplastic theory of welding simulation, which was studied based on the thermodynamic coupling algorithm with a software-developed application for the SLM process. Subsequently, typical case results of thin and hollow plate part formation and the corresponding performances were simulated in detail. The results demonstrated that the effective thermal stress increased as the layer height increased from the surface layer to the substrate, while the thermal strain followed an approximate change rule. In addition, the stress was released from the underlying substrate when the support was removed. Moreover, the largest single axis plane stress was changed from tension to compression from the edge to the center, finally reaching equilibrium. In particular, maximum macro thermal deformation occurred at the printed support structure to the samples, displaying similar results in other locations such as the corners. Finally, the effectiveness of the simulation could be verified from the realistic printed part, which could provide proof for the quality prediction of the part that is actually forming.

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Study on Numerical Simulation Method of Periodic Symmetric Struts Support Coupling with Heat Flow and Solid

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.462-463.985 ◽

2011 ◽

Vol 462-463 ◽

pp. 985-989

Author(s):

Mamtimin Gheni ◽

Zhen Shi Li ◽

Wei Cheng ◽

Wei Bing Liu ◽

Lie Yu

Keyword(s):

Thermal Stress ◽

Gas Turbine ◽

Thermal Deformation ◽

Large Scale ◽

Gas Flow ◽

Initial Boundary ◽

Simulation Method ◽

Heat Transfer Process ◽

Element Analysis ◽

Two Phases

In this paper, the fluid solid coupling method is used and the FE (Finite Element) analysis is conducted for the PSSS (Periodic Symmetric Struts Support) of the large scale GT(Gas Turbine), and the overall thermal stress and thermal deformation are obtained. From the structure feature of the gas turbine, the initial boundary conditions of the high-temperature gas flow field and thermal deformation are analyzed at first. Then the coupling relationship between fluid and solid two phases is expressed mathematically, and the thermal conductivity is considered for calculation of heat transfer process, and the overall temperature field is obtained. Finally the thermal boundary condition of PSSS is defined and the structural FE analysis is conducted. At the same time, the thermal stress field and thermal deformation field are discussed for overall PSSS structure.

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An adaptive heat source model for finite-element analysis of keyhole plasma arc welding

Computational Materials Science ◽

10.1016/j.commatsci.2009.02.018 ◽

2009 ◽

Vol 46 (1) ◽

pp. 167-172 ◽

Cited By ~ 50

Author(s):

C.S. Wu ◽

Q.X. Hu ◽

J.Q. Gao

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Heat Source ◽

Arc Welding ◽

Source Model ◽

Plasma Arc Welding ◽

Plasma Arc ◽

Heat Source Model ◽

Element Analysis

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Effect of Water Pipe Cooling on Thermal Stress of FuYang River Aqueduct Structure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.438-439.569 ◽

2013 ◽

Vol 438-439 ◽

pp. 569-572

Author(s):

Xin Li Bai ◽

Jiang Yan Li ◽

Qian Pan

Keyword(s):

Temperature Field ◽

Thermal Stress ◽

Simulation Method ◽

Water Pipe ◽

Analysis Model ◽

Element Analysis ◽

Crack Location ◽

Cooling Pipe ◽

Calculation Results ◽

Water Pipe Cooling

In order to analyze the influence rule of water pipe cooling on the temperature field and thermal stress of large aqueduct structure, the finite element analysis model for FuYang River Aqueduct structure was established. The temperature field and thermal stress of the aqueduct structure were calculated. The following two cases were considered: structure with or without water pipe cooling, as well as the different beginning pouring months (May, June and July). The hydration-degree-based calculation methods of temperature and stress of concrete were adopted, and the high precision discrete simulation method of water pipe was used. The calculation results show that embedding the cooling pipe in concrete can effectively reduce the temperature difference between inside and outside of the early concrete and thermal stress, and is therefore effective to prevent concrete cracks. High accuracy of simulation and analysis can make people basically figure out the specific mechanism of concrete cracking and main factors even before construction, and determine accurately the structure crack location and the developing tendency.

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Numerical Analysis of Liquid Ammonia Storage Tank Welding Stress

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.217-219.1954 ◽

2012 ◽

Vol 217-219 ◽

pp. 1954-1958

Author(s):

Zhang Lei

Keyword(s):

Finite Element ◽

Thermal Stress ◽

Temperature Distribution ◽

Storage Tank ◽

Liquid Ammonia ◽

Source Model ◽

Ansys Software ◽

Heat Source Model ◽

Welding Stress ◽

Thermal Stress Distribution

Welding is the main means of the connection of tank, is also an important factor in determining tank quality. Applied Ansys software, finite element modeling, Choosed a reasonable heat source model to analyze the temperature distribution and variation of the weld, obtained the weld thermal stress distribution of the quantitative laws, it provides a good help to improve the security of the pressure vessel.

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Heat Source Model of Lap Laser Welding of Stainless Steel Vehicle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.121-126.3347 ◽

2011 ◽

Vol 121-126 ◽

pp. 3347-3351 ◽

Cited By ~ 2

Author(s):

Hong Xiao Wang ◽

Chun Sheng Wang ◽

Chun Yuan Shi ◽

Zhi Yi Huang

Keyword(s):

Stainless Steel ◽

Heat Source ◽

Laser Welding ◽

Process Parameters ◽

Production Efficiency ◽

Three Dimensional ◽

Source Model ◽

Heat Source Model ◽

Element Analysis ◽

Welding Temperature

Resistance spot welding (RSW) is being taken place by partial lap laser welding for the poor surface quality and bad airtight due to the pressure of electrodes. The shape of partial lap laser welding is similar to the vase. When the penetration of the joint is in a certain range, there is no welding trace on the outer surface. Laser welding temperature field numerical analysis based on Abaqus finite element analysis software is committed to obtain a suitable range of process parameters to improve production efficiency and automation by determining the joint penetration. To master the laser lap welding of stainless steel weld penetration state, the combination of three-dimensional positive cone + three-dimensional inverted cone + half-ellipsoid heat source model was established simulating stainless steel lap laser weld pool shape and forecasting the range of process parameters .

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Effects of Heat Source Model and Welding Speed on Welding Temperature Field for a Plan Carbon Steel Plant

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.488-489.83 ◽

2014 ◽

Vol 488-489 ◽

pp. 83-89 ◽

Cited By ~ 1

Author(s):

Z.K. Song ◽

Z.Y. Li ◽

J. Xu ◽

Y.C. Sun

Keyword(s):

Temperature Field ◽

Carbon Steel ◽

Heat Source ◽

Welding Speed ◽

Heat Input ◽

Source Parameters ◽

Source Model ◽

Heat Source Model ◽

Element Analysis ◽

Welding Temperature

This article studies the effects of heat source shape parameter and welding speed on the evolution of welding temperature field for Q345 plan carbon steel. The heat input and heat source parameters as well as the welding speed are defined by applying DFLUX subroutine in ABAQUS to simulate the transient welding temperature. The effects of heat resource shape parameters and heat input as well as the welding speed on welding temperature field are investigated by means of finite element analysis. It has been found that heat source parameters and welding speed show strong influence on temperature distribution in FZ (fusion zone) and HAZ (heat-affected zone). Meanwhile, it shows a roughly linear relationship between the changes of heat input and the highest temperature.

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Estimation of Heat Source Model’s Parameters for GMAW with Non-linear Global Optimization—Part I: Application of Multi-island Genetic Algorithm

Metals ◽

10.3390/met10070885 ◽

2020 ◽

Vol 10 (7) ◽

pp. 885

Author(s):

Changmin Pyo ◽

Jisun Kim ◽

Jaewoong Kim

Keyword(s):

Genetic Algorithm ◽

Finite Element Analysis ◽

Finite Element ◽

Global Optimization ◽

Heat Source ◽

Source Model ◽

Boundary Line ◽

Welding Deformation ◽

Heat Source Model ◽

Element Analysis

Estimating the thermo-elasto-plastic deformation by arc welding through finite element analysis has been used in various industrial fields. The Goldak heat source model is one of the most important and widely used models in finite element analysis, and its parameters are estimated based on the results of previous studies and tests. Part I of this study focused on the adequate heat source model, and the study for the welding deformation with the moving heat source will be done on the latter research. This study used the parameters of Goldak’s heat source model, weld efficiency, and the location of the heat source as design variables, and defined the Heat Affected Zone (HAZ) boundary line of Bead on Plate (BOP) welding as the target. BOP welding was performed using SS400 plates, the HAZ boundary line was determined based on examining the shape of the cross-section, and the optimization condition was that temperature inside the boundary line exceeded 727 °C while the temperature outside the line did not exceed 727 °C during the welding process. During this process, a multi-island genetic algorithm (non-linear global optimization method) was used to obtain the optimal results out of 1000 candidate groups, in which the HAZ boundary was similar to the experimental results. Applying a global optimization algorithm to determine the parameters of the most important heat source model to analyze welding deformation is significant, and this may be applied in various industrial fields that use welding including shipbuilding, aviation, and machinery industries.

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