Plastic Strain Distribution Research Articles

Resistance mechanism of partially embedded pipelines considering the influence of temperature fields

Subsea pipelines are prone to global buckling under high temperature and high pressure. The key to predict buckling is to accurately evaluate the pipe-soil resistance, which is affected by the soil temperature. The effect of temperature on axial resistance has been investigated, but the impact on the transverse resistance has not been well considered. In this paper, incorporating the heat transfer analysis of partially embedded pipelines, finite element models are established to reveal how temperature affects the resistance. The yield envelope of pipe-soil resistance under different temperatures is presented. The results show that the resistance is positively correlated with temperature. Specifically, it is found that the pipeline (w/D=0.5) with high temperature (80 °C) exhibits 23.49% larger maximum pipe-soil resistance than the low temperature pipeline (4 °C). Meanwhile, the temperature affects the plastic strain distribution in the soil, which changes the soil failure mode. In addition, the yield envelope and dividing point between light and heavy pipelines increase significantly with the rise in temperature. Finally, the constructed yield envelopes are adopted in the pipeline buckling model. It shows that lateral pipeline buckling is obviously suppressed by the temperature rise. The research provides a guidance for controlling the buckling of pipelines.

Modeling and simulation of laser shock waves in elasto-plastic polycrystalline microstructures

We study the propagation of elasto-plastic shockwaves induced by high power laser impacts in 2D polycrystalline metallic alloys in order to investigate the influence of the material microstructure on the fields of plastic strain and subsequent residual stresses. Implementing a visco-plastic constitutive relation at the grain scale accounting for two dislocation slip systems into a finite volume numerical scheme, simulations on single crystal specimens with different lattice orientations show that plastic strain is concentrated in narrow bands originating at the edges of the laser impact and parallel to the slip planes. In the case of polycrystalline microstructures composed of randomly oriented grains, it is found that the microstructure morphology is the origin of a heterogeneous distribution of the residual plastic strain and stress fields, which thus departs from the residual stress fields usually modeled when the microstructure is not accounted for. To account for the random character of polycrystal microstructures, we perform a statistical analysis of the mechanical fields over a large number of microstructures to quantify the dispersion of the results. It is found that even though the residual stresses induced by a laser impact are in compression on average at the center of the laser impact, some realizations of the microstructures can lead to localized concentrations of less compressive, or even tensile, residual stresses at the surface, thus probably reducing the fatigue resistance of the shocked material.

Geometric deformation prediction of a centrifugal impeller considering welding distortion and fluid-structure interaction

An impeller serves in a centrifugal fan, pushes the surrounding air and in turn reacts on itself. The fluid-to-structure response and part welding distortion during the fabrication and working processes will cause the impeller to deform and reduce fan performance. This work develops a numerical simulation approach and focuses on two essential factors: welding distortion and distortion induced by fluid to structure interaction. The research target was an impeller comprising five thin-plate curved fillet joints, and its total distortion was predicted using the proposed approach. First, the structure of the impeller was modeled with solid elements, and each welded local joint's welding distortion was measured with a modified inherent strain method. A one-way fluid-structure coupling analysis carefully examined the distortion induced by Fluid-Structure Interaction (FSI) from the fluid medium and coupling surfaces. Then, an interpolation method was conducted to compute the welding and FSI distortion contours using a simple structural analysis. To determine the inherent strain in a curved and non-curved fillet joint, a detailed transient analysis by the Thermal Elastic Plastic (TEP) Finite Element Method (FEM) and their welding distortion, plastic strain distribution, and inherent deformation are discussed. The welding and flow field tests both agree with the simulation results, confirming the modified inherent strain method and relevant FSI results. Thus, the developed approach can provide a suitable reference for controlling distortion in welded fans and related fluid machinery.

Effects of Cold Expansion on Residual Stress of 7050 Aluminium Alloy Frame Forging

Regulation of residual stress in a component is the key to improving its service performance. A cold expansion method was proposed for reducing the residual stress in 7050 aluminium alloy curved frame forging after quenching. The effect of the cold expansion method on the residual stress and equivalent plastic strain distribution of the 7050 aluminium alloy curved frame forging was investigated. The results showed that the maximum residual stress at the center thickness was reduced from 153 MPa to 94 MPa after the cold expansion, while it decreased from 283 MPa to 120 MPa at the surface with the highest stress reduction rate of 86.2%. The stress uniformity in the final forming region of the forging was improved. The equivalent plastic strain of the forging gradually decreases from the center to each side along the diameter of the expanded hole in cold expansion. The stress reduction effect matched with the distribution of equivalent plastic strain. The surface stress of the forging measured by x-rays diffraction (XRD) method was in agreement with the simulation results, and the reliability of the numerical model was verified. The cold expansion method can effectively reduce the quenched residual stress in curved frame forging.

The influence of crustal strength on rift geometry and development – insights from 3D numerical modelling

Abstract. The lateral distribution of strength within the crust is non-uniform, dictated by crustal lithology and the presence and distribution of heterogeneities within it. During continental extension, areas of crust with distinct lithological and rheological properties manifest strain differently, influencing the structural style, geometry, and evolution of the developing rift system. Here, we use 3D thermo-mechanical models of continental extension to explore how pre-rift upper-crustal strength variations influence rift physiography. We model a 500×500×100 km volume containing 125 km wide domains of mechanically “strong” and “weak” upper crust along with two reference domains, based upon geological observations of the Great South Basin, New Zealand, where extension occurs parallel to the boundaries between distinct geological terranes. Crustal strength is represented by varying the initial strength of 5 km3 blocks. Extension is oriented parallel to the domain boundaries such that each domain is subject to the same 5 mm yr−1 extension rate. Our modelling results show that strain initially localises in the weak domain, with faults initially following the distribution of initial plastic strain before reorganising to produce a well-established network, all occurring in the initial 100 kyr. In contrast, little to no localisation occurs in the strong domain, which is characterised by uniform strain. We find that although faults in the weak domain are initially inhibited at the terrane boundaries, they eventually propagate through and “seed” faults in the relatively strong adjacent domains. We show characteristic structural styles associated with strong and weak crust and relate our observations to rift systems developed across laterally heterogeneous crust worldwide, such as the Great South Basin, New Zealand, and the Tanganyika Rift, East Africa.

In-situ fabrication of repairing layers for large structures using follow-up hot-hammering-assisted wire arc additive manufacturing

The development of a spherical hammer head follow-up hot-hammering-assisted (FH) hybrid wire arc additive manufacturing enables the application of the hammering-assisted process to the in-situ repair of large-scale structural parts. This process allows for large deformation in the deposited weld bead with lower energy input at higher temperatures, resulting in less work hardening. A thermal, mechanical and plastic deformation coupled finite element model is established to analyze the plastic strain distribution with different shapes of hammer heads and different deformation history. Compared with the flat hammer head, the spherical hammer head is more likely to produce large plastic deformation in deposited weld bead under the same force and energy conditions, and obtain more uniform microstructure. Different hammering temperatures higher than austenite recrystallization temperature with the spherical hammer head, are selected to study the effect on grain refinement of repairing layers. The OM, XRD, SEM and EBSD are used for grain, texture evolution and strengthening mechanism analysis. The results show that by introducing the spherical hammer head FH process at 980 °C slightly higher than the austenite recrystallization temperature, the grain size decreases gradually from the bottom repairing layer to the top one, showing a genetic evolution law. The topmost repairing layer grain size is refined from 353 μm to 30 μm, the average grain size of repairing layers is refined from 361 μm to 62 μm, and the strong {100} texture of the topmost repairing layer is reduced to be approximately random. The grain refinement is attributed to the combined influence of recrystallization and co-generation crystallization. Meanwhile, the yield strength is significantly improved, and the main strengthening mechanisms are grain refinement strengthening and dislocation strengthening, and the contributions are 42.0 MPa and 101.4 MPa.

A procedure to obtain correlation curve between local misorientation and plastic strain

Numerous studies have assessed the degree of plastic strain induced in polycrystalline materials using crystal orientation mapping data obtained by electron backscatter diffraction. However, it was pointed out that the local misorientation, defined as the averaged misorientation between adjacent measurement points, was difficult to use for a quantitative assessment because the magnitude of the local misorientation was affected by various measurement conditions including the step size, that is the spacing of the crystal orientation measurement points. To quantitatively assess the local misorientation, this study proposed a procedure for estimating the correlation curve between the local misorientation and the degree of plastic strain, which is referred to as the master curve. The procedure to determine the master curve was proposed using Type 316 stainless steel specimens of various degrees of plastic strain. The procedure was based on the characteristics of the change in the misorientation parameters due to the measurement conditions that were investigated using the crystal orientations obtained for various conditions and specimens. It was shown that similar local plastic strain distributions were obtained regardless of the measurement conditions, including especially the step size. From the findings, it was recommended that a smoothing filter should be applied when making a quantitative assessment of the local misorientation.

Failure Modelling of CP800 Using Acoustic Emission Analysis

Advanced high-strength steels (AHHS) are widely used in many production lines of car components. For efficient design of the forming processes, numerical methods are frequently applied in the automotive industry. To model the forming processes realistically, exact material data and analytical models are required. With respect to failure modelling, the accurate determination of failure onset continues to be a challenge. In this article, the complex phase (CP) steel CP800 is characterised for its failure characteristics using tensile tests with butterfly specimens. The material failure was determined by three evaluation methods: mechanically by a sudden drop in the forming force, optically by a crack appearing on the specimen surface, and acoustically by burst signals. As to be expected, the mechanical evaluation method determined material failure the latest, while the optical and acoustical methods showed similar values. Numerical models of the butterfly tests were created using boundary conditions determined by each evaluation method. A comparison of the experiments, regarding the forming force and the distribution of the equivalent plastic strain, showed sufficient agreement. Based on the numerical models, the characteristic stress states of each test were evaluated, which showed similar values for the mechanical and optical evaluation method. The characteristic stress states derived from the acoustical evaluation method were shifted to higher triaxialities, compared to the other methods. Matching the point in time of material failure, the equivalent plastic strain at failure was highest for the mechanical evaluation method, with lower values for the other two methods. Furter, three Johnson–Cook (JC) failure models were parametrised and subsequently compared. The major difference was in the slope of the failure models, of which the optical evaluation method showed the lowest slope. The reasons for the differences are the different stress states and the different equivalent plastic strains due to different evaluation areas.

Experimental study on low-damage performance of Sliding Hinge Joint

The Sliding Hinge Joint (SHJ) is a low damage beam-to-column joint primarily for moment resisting steel frames (MRSFs). It is intended to remain rigid during frequent earthquake events, while rotation occurs between the column and beam under design basis earthquake events. At the end of earthquake events, the joint is expected to seize up and become rigid again. However, residual strength and stiffness of the SHJ are considerably reduced even within design-level sliding. The objective of this study is to evaluate resilience and repairability of the SHJ by carrying out cyclic loading on a full-scale beam-to-column assembly considering both design-level sliding and post design-level sliding. Overall, the SHJ exhibited a predictable and stable hysteretic response. It was concluded that the SHJ experienced a 79.5% decrease in average moment resistance and a 59.4% decrease in elastic rotational stiffness with no repair actions taken. Resilience of the joint could be achieved by replacing and retightening the asymmetric friction connection (AFC) bolts to bring the joint back to an as-built condition. Moreover, a detailed finite element model was developed to further investigate the plastic strain distribution, frictional sliding and energy dissipation behaviours of the joint, and the low-damage performance was verified. Finally, a simplified analytical model based on the component method was proposed to predict the joint behaviour.

Study on hot deformation behavior of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy using a combination of strain-compensated Arrhenius constitutive model and finite element simulation method

Isothermal hot compression experiments were conducted on homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy to investigate hot deformation behavior at the temperature range of 673–773 K and the strain rate range of 0.001–1 s − 1 by using a Gleeble-1500D thermo mechanical simulator. Metallographic characterization on samples deformed to true strain of 0.70 illustrates the occurrence of flow localization and/or microcrack at deformation conditions of 673 K/0.01 s − 1, 673 K/1 s − 1 and 698 K/1 s − 1, indicating that these three deformation conditions should be excluded during hot working of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy. Based on the measured true stress-strain data, the strain-compensated Arrhenius constitutive model was constructed and then incorporated into UHARD subroutine of ABAQUS software to study hot deformation process of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy. By comparison with measured force-displacement curves, the predicted results can describe well the rheological behavior of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy, verifying the validity of finite element simulation of hot compression process with this complicated constitutive model. Numerical results demonstrate that the distribution of values of material parameters (α, n, Q and ln A) within deformed sample is inhomogeneous. This issue is directly correlated to the uneven distribution of equivalent plastic strain due to the friction effect. Moreover, at a given temperature the increase of strain rate would result in the decrease of equivalent plastic strain within the central region of deformed sample, which hinders the occurrence of dynamic recrystallization (DRX).

Stored energy density research on the fatigue crack initiation at twin boundary and life prediction of Inconel718 superalloy

The fatigue crack initiation at twin boundary (TB) and the life prediction of IN718 alloys in the high cycle fatigue (HCF) regime and very high cycle fatigue (VHCF) regime were investigated through crystal plasticity finite element (CPFE) simulations and experiments. The fatigue damage parameter, considering the evolution of geometrically necessary dislocation (GND) density, slip and back stress, known as the back-stress-based stored energy density in this study, Gba, was proposed to precisely characterize the plastic strain distribution and localization, which in turn was engaged in locating fatigue crack initiation site and predicting the fatigue life. The element analysis around TB and the CPFE simulations indicated the coupling of slip activation parallel to the TB and the absence of primarily strengthening phase (γ'') on the both side near the TB was responsible for crack initiation. To predict fatigue life, the varying pattern of the Gba at fracture with fatigue life was studied based on the experimental results in the HCF and VHCF regimes, and the life prediction method was obtained accordingly. Finally, the fatigue life evaluations of the IN718 alloy at three load ratios (R = −0.1, 0.1, and 0.5) were conducted and results showed that the life estimates were basically within ±3 scatted bands.

The effect of Mn containing dispersoids on the distribution of slip and fracture mode in Al-Mg-Si-Mn alloys

Improvements in the fracture performance of Al-Mg-Si extrusions are required to meet the demands of the automotive market. The fracture mode and the associated ductility results from competition between transgranular and intergranular fracture paths where intersection of slip bands and grain boundaries plays a significant role. In this study, the distribution of plastic strain within grains for microstructures with different spacings of Mn dispersoids was quantified using high resolution digital image correlation. It was observed that plastic strain was organized into slip bands where the magnitude of local shear strain decreased with reduced inter particle spacing of the dispersoids. It is proposed that this leads to a lower stress concentration on the grain boundary, decreasing the propensity for intergranular fracture. This was consistent with the findings that intergranular fracture was dominant in the dispersoid free material whereas low and high densities of dispersoids gave rise to a transgranular fracture mode.

Microstructure based numerical simulation of the micromechanics and fracture in hypereutectic Al–Mg2Si composites

In the present study, both experimental and numerical examinations were performed to understand the hypereutectic Al–Mg2Si composite's microstructural morphology, mechanical properties and fracture correlation. The innovation of this research includes the micromechanics studies and failure initiation in hypereutectic Al–Mg2Si composite through the compiled induce stress, deformation plasticity and energy dissipation theory subjected to tension. Ultimate tensile strength (UTS), toughness and elongation have decreased, but the yield strength has increased up to 25% Mg2Si addition and then decreased at the composites with 30 wt% Mg2Si because the brittle fracture increases due to the presence of comparatively coarser and dendritic primary Mg2Si particles. Additionally, an increase in the microporosity with the increase in Mg2Si concentration also affects the same. Finite element analysis (FEA) was performed using the Ramberg-Osgood constitutive model and actual microstructure 2D representative volume elements model. The FEA and experimental results have a satisfactory agreement. The fractography unveils the presence of a mix-mode of fracture, i.e. the ductile and the brittle fracture of the composites. Mises and Tresca failure criteria reveal that the distribution of stress is non-homogeneous and stress is localized in the narrow eutectic and irregular Mg2Si phase region, which acts as a crack initiation site. Analysis of the stress triaxiality and equivalent plastic strain distribution shows that void initiation and growth take place during the deformation of the Al–Mg2Si composites. The plastic dissipated energy distribution in deformed RVEs interestingly consents to the von mises stress, plastic strain and stress triaxiality analysis findings.

Role of Persistent Slip Bands and Persistent Slip Markings in Fatigue Crack Initiation in Polycrystals

The cyclic plastic deformation of polycrystals leads to the inhomogeneous distribution of the cyclic plastic strain. The cyclic plastic strain is concentrated in thin bands, called persistent slip bands (PSBs). The dislocation structure of these bands generally differs from the matrix structure and is characterized by alternating dislocation-rich and dislocation-poor regions. The mechanisms of the dislocation motion in the PSBs and the formation of the point defects and their migration are quantitatively described. It is shown that, due to localized cyclic plastic straining in the PSBs, persistent slip markings (PSMs) are produced where the PSBs emerge on the surface. They typically consist of a central extrusion accompanied by one or two parallel intrusions. The deep intrusion is equivalent to the crack-like surface defect. The concentration of the cyclic strain in the tip of an intrusion leads to intragranular fatigue crack initiation. The mechanism of the early crack growth in the primary slip plane is proposed and discussed. Numerous PSMs are produced on the surface of the cyclically loaded materials. PSMs contribute to the formation of the surface relief, as well as the relief on the grain boundary. PSMs from one grain impinging the grain boundary are sufficient to create sharp relief on the grain boundary. Void-like defects weaken the grain boundary cohesion and extra material push both grains locally apart. The conditions necessary for the weakening of the grain boundary are enumerated and examples of grain boundary crack initiations are shown. The relevant parameters affecting grain boundary initiation are identified and discussed. The collected experimental evidence and analysis is mostly based on the papers published by the author and his colleagues in the Institute of Physics of Materials in Brno.

Optimizing the ECAP processing parameters of pure Cu through experimental, finite element, and response surface approaches

Abstract The main aim of the current work is to investigate the effect of equal channel angular pressing (ECAP) processing parameters, namely, number of passes, ECAP die angle, route type, and processing temperature on the mechanical and electrical properties of pure copper (Cu). The finite element method was used to simulate the homogeneity of stress and plastic strain distribution during ECAP processing. The response surface methodology (RSM) was used to identify the optimum ECAP processing parameters by analyzing the impact of ECAP conditions on responses. A second-order regression model and analysis of variance were created to analyze the ECAP condition of optimum responses. A genetic algorithm (GA) was also applied to optimize the ECAP condition. Finally, a hybrid RSM–GA was created to improve the optimization of ECAP responses and corresponding conditions evaluated using GA. The developed models were validated and compared with the experimental findings to prove that they are reliable as predictive tools. The optimization findings revealed that route Bc was more effective in improving the hardness, yield stress, ductility, and impact energy whereas route A was more effective in improving the ultimate tensile strength and the electrical conductivity of the Cu billets. Furthermore, the optimum die angle, number of passes, and processing temperature for the mechanical and electrical properties were also identified individually.

Characterization of gradient plastic deformation in gradient nanotwinned Cu

Gradient nanostructured (GNS) metals exhibit high overall extra strengths relative to their non-gradient counterparts. However, the spatial distribution of local extra strengths stemming from plastic strain gradients remains elusive. This work is focused on characterizing the gradient distribution of plastic strains in a representative GNS metal of gradient nanotwinned (GNT) Cu. Full-field strain mapping reveals the gradient distributions of lateral strains in the transverse cross section of GNT Cu samples undergoing uniaxial tensile deformation. We find that the lateral strain gradient increases but the maximum lateral strain difference decreases in GNT samples with increasing structural gradient. The latter arises because the softest layer with the lowest initial yield strength gains the largest local extra strength during tensile deformation, and vice versa. Such a gradient distribution of local extra strengths results from the combined strengthening effects of plastic strain gradient and grain size. These experimental results are used to inform a strain gradient plasticity model for revealing the gradient distributions of local extra back stresses and local extra strengths with increasing load. The coupled experimental and modeling characterization of gradient plastic deformation provides an in-depth mechanistic understanding of the spatial-temporal evolution of gradient strengthening effects in gradient nanostructures.

Finite element-based comparative investigation of incremental forming and elevated temperature incremental forming

Incremental forming (IF) is a non-traditional forming process to transform sheets into useful components without using devoted tooling and die arrangements. The execution of IF at higher temperatures is known as elevated temperature incremental forming (ET-IF). This work compares the IF and ET-IF processes through the finite element analysis (FEA) approach. The FEA results are compared in terms of stress, plastic strain, and sheet thickness distribution, along with forming depth achieved for the two processes. A descriptive statistical analysis of the results has been performed to strengthen the outcomes. Also, some of the results are compared with the outcome of experimentation available in the literature. It is perceived that the formability extensively improves with the ET-IF process in comparison to that of IF at room temperature. Besides, it has been observed that increased temperatures prominently enhance the quality of the IF process. [Submitted 27 August 2021; Accepted 19 March 2022]

Surface Microstructure Refinement and Mechanical Properties of GCr15 Steels Improved During Ultrasonic Surface Rolling Processing

In this paper, ultrasonic surface rolling processing (USRP) was used to strengthen GCr15-bearing steel. A finite element three-dimensional model of USRP was established to analyze the residual compressive stress and equivalent plastic strain distribution on the bearing steel surface. The microstructure, hardness, surface roughness, and corrosion resistance before and after USRP treatment were characterized by SEM, EBSD, X-ray diffraction (XRD), and electrochemical techniques. Results indicated that USRP treatment can significantly improve the material's surface microstructure and residual compressive stress distribution and obtain a plastic strain layer of about 60μm. After USRP treatment, the Kernel Average Misorientation (KAM) increased, and the dislocation activity was more intensive, resulting in aggregation near grain boundaries, and the percentage of LAGBs increased to 38.8%. Under the combined effect of surface grain refinement, residual compressive stress, and high glossy surface, the self-corrosion current density is reduced by two orders of magnitude, and the corrosion resistance is significantly improved. This investigation suggests a solution to the bearing failure problem and has implications for understanding the deformation mechanism of ultrasonic surface rolling processing.

Understanding the bending behavior and through-thickness strain distribution during asymmetrical rolling of high-strength aluminium alloy plates

The asymmetric rolling (ASR) process is highly desired to improve the through-thickness deformation/strain uniformity by introducing additional shear strains for uniform through-thickness microstructures and mechanical properties of metallic/alloy plates. In this study, the bending behavior and mechanism during the ASR processing of high-strength AA7050 aluminium alloy plates were simulated along with rolling trials. It shows that the plate will bend upward (toward slower roll) at larger speed ratios and smaller thickness reductions but downward (toward faster roll) at smaller speed ratios and larger thickness reductions. The ASR processing can increase the central equivalent plastic strains and decrease the surface-to-center strain gradient compared with that caused by the conventional symmetric rolling. The high strain rate bands (HSRBs) as key plastic strain accumulation regions are intimately connected with the post-rolling equivalent plastic strain distribution and the outgoing curvature. Especially, when the HSRB approaches the plate upper surface near the end of the deformation zone, normally at larger thickness reductions, a downward bending occurs despite that the lower roll rotates faster, and vice versa. The through-thickness HSRB induced by the ASR processing is considered to mainly enhancing the equivalent plastic strain homogeneity. The formation and interactive mechanisms of the HSRBs and their connection with the bending behavior during the ASR processing were discussed.

Optimization of Ti-6Al-4V ring rolling process by FE simulation using RSM

Ring rolling is a process to manufacture seamless rings. The process is characterised by high non-linearity, asymmetry, unsteady state and non-uniformities in plastic strain and temperature distribution in the ring cross-section. Inhomogeneities in distribution of plastic strain and temperature have significant effects on deformation behavior, microstructure and mechanical properties. Fishtail defect, one of the form defects, is also a major concern. In this study, a reliable coupled 3D thermo-mechanical finite element model of the ring rolling process was developed using dynamic explicit code in ABAQUS/Explicit environment. Nine simulations with different combinations of feed rate and rotational speed were ascertained using Central Composite Design (CCD). CCD model is an integral part of Response Surface Methodology (RSM). Strain and temperature heterogeneities and fishtail defect were predicted using the simulated models. Coefficient of Variation (CoV) was introduced as a heterogeneity index for strain and temperature analysis. The fishtail coefficient was used to quantify fishtail defect. ANOVA was carried to find out the significant factors and interactions affecting the ring rolling process. Feed rate was found to be the only significant factor in the range of parameters studied. Multi-response optimization was performed to find out the feed rate at which the process is most optimized with an aim to minimize both strain and temperature heterogeneity and fishtail defect. Feed rate of 1.61 mm/s was found to be the most optimized process parameter.