Papers by Perumalla Ramulu
Materials Science Forum, Aug 1, 2019
In recent years, there is a lot of demand on metal forming processes in which sheet metal forming... more In recent years, there is a lot of demand on metal forming processes in which sheet metal forming process has lots of applications in the automotive and aerospace industries. In sheet metal forming operations, incremental forming is an emerging technology in which, single point incremental forming (SPIF) process is die-less in incremental forming process and providing a competitive alternative to economical and effective in fabricating low volume products. The objective of this work is to analyze the forming analysis on truncated pyramid product by avoiding cracking and maintaining the optimum forming conditions. The formability is analyzed by using ABAQUS software and simulation, different process parameters were varied such as sheet thickness, tool diameter, step depth, spindle rotational speed on aluminum AA1050 alloy. From the simulation results, stress stain and stain distribution were evaluated on the deformed sheet. The product produced is truncated pyramid dimension having square base of side and fillet at corner.
Manufacturing Technology, Jun 22, 2023
Materials Today: Proceedings, 2019
In this paper, the effect of modified (OMt) nanoclay polyester resin on low velocity impact damag... more In this paper, the effect of modified (OMt) nanoclay polyester resin on low velocity impact damage area and damage tolerance capability of untreated woven jute and glass fabric hybrid sandwich laminates have been investigated experimentally. The Hybrid Sandwich Laminates are prepared by hand lay-up manufacturing technique (HL) for investigation with a total of 10 layers. For comparison of the composite with hybrid composite, jute fiber reinforced composite laminate is also fabricated. Low velocity impact and Compression After Impact (CAI) tests are carried out on all the fabricated laminates to evaluate damage area and damage tolerance capability respectively. X-ray Diffraction (XRD) results have been obtained from the samples, where the nanoclay has indicated that intergallery spacing of the layered clay increases with matrix. The results of the study show that the damage tolerance capability of the nano polyester hybrid sandwich has been greatly increased and the damage area is decreased at 4% of nanoclay loading.
Advances in Materials Science and Engineering, Feb 8, 2023
Research and developments on preparing electrode material for lithium-ion batteries are burgeonin... more Research and developments on preparing electrode material for lithium-ion batteries are burgeoning nowadays widely. In this study, we used the high energy ball-milling method to prepare pure and samarium-doped lithium manganese oxide (Li 4 Mn 5 O 12 ) and investigated its structural, morphological, and electrical properties. Te XRD spectrum for the produced materials confrmed the phase purity and crystallinity of the material. Te fourier transform infrared spectrum was used to determine the diferent sorts of vibrations between molecules. Te particle size with the presence of polyhedral-shaped morphology was certifed by using SEM and TEM analysis. EDS mapping was used to assess the elemental composition and purity of the samples. Complex impedance spectroscopy analysis was used to investigate the temperature dependency of the materials' electrical properties, and high conductivity (1.15 × 10 -7 S cm -1 ) was reported for samarium-doped lithium manganese oxide at 100 °C, and its dielectric relaxation behavior was examined.
ESAFORM 2016: Proceedings of the 19th International ESAFORM Conference on Material Forming, 2016
Advances in Materials Science and Engineering, Apr 25, 2023
Lecture notes on multidisciplinary industrial engineering, 2019
Wonji Shoa Sugar Factory (WSSF) is one of the top sugar factories in Ethiopia which produces suga... more Wonji Shoa Sugar Factory (WSSF) is one of the top sugar factories in Ethiopia which produces sugar and electricity from sugarcane using three critical plants: mill plants, sugar processing plant, and a cogenerating power plant. Among three plants, the mill plant is the most important plant used to crush the cane for separating sugar juice from bagasse. In this plant, Fibrizer hammer device is used for cruising sugarcane. The Fibrizer performs the major share in milling process for fibrizing the chopped cane after set of cane knives using rotating knives. Most of the times, WSSF is facing breakages of Fibrizer hammer by which losses incurring to the factory. The main aim of the paper is to analyze the failure causes of existing Fibrizer hammer with respect to design and modify the necessary changes in design for Fibrizer hammer at WSSF. By which, get high preparation index (PI) and optimize in power consumption and cost. In addition, hardness of the existing Fibrizer hammer was tested to know the mechanical strength. For modification of existing Fibrizer hammer: comparison was made in terms of design, and load along with harmonic simulation analyses performed using finite element analysis. The results from finite element analysis revealed that the modified Fibrizer hammer
International Journal of Polymer Science, Apr 19, 2023
Lecture notes on multidisciplinary industrial engineering, 2019
Sheet metal forming is a process widely used in the manufacturing industry. There are several she... more Sheet metal forming is a process widely used in the manufacturing industry. There are several sheet metals forming processes are existing including stretch forming process. In the present work, stretch formability of AA6023-T6 sheet of 2 mm thickness at room temperature and annealed sheet at 400 °C has been performed. For which mechanical properties were evaluated through tensile test for all the conditions. For stretching operations, simulations were performed using limit dome height (LDH) test using PAM STAMP 2G software. During LDH test, the maximum value of LDH for annealed sheets of AA6023-T6 at 400 °C and minimum value for sheets at room temperature is observed. Uniform thickness distribution for annealed blanks at 400 °C is observed compared to room temperature. The room temperature stretch formability of AA6023-T6 alloy sheet has 39.5 maximum dome height and annealed sheet at 400 °C has 43 maximum dome heights. By which, annealed AA6023-T6 sheet has good stretch formability compared to room temperature stretch formability.
Nucleation and Atmospheric Aerosols, 2022
Journal of Natural Fibers
Advances in Materials Science and Engineering, Jan 12, 2022
In this study, NACA0018 airfoil surface conformity test was conducted using API tracker3 in combi... more In this study, NACA0018 airfoil surface conformity test was conducted using API tracker3 in combination with SpatialAnalyzer (SA) and modeling software SolidWorks. Plaster of Paris is used as a plug making material and a woven-type fiberglass is used as mold and airfoil surface making material. For airfoil surface analysis, three-dimensional model of the airfoil surface was developed in SolidWorks software and imported in IGES file format to SpatialAnalyzer (SA) software. en, measurements were taken from manufactured airfoil surface using laser tracker through surface scanning method. Surface conformity test was conducted through fitting of measured points to surface model imported from SolidWorks to SpatialAnalyzer (SA) software. e optimized fit summary result shows that the average fit difference is 0.0 having standard deviation from 0.22224 from the average and zero with RMS of 0.2210. e maximum magnitude of the difference including x and y together is 0.5336 and the minimum -0.5077. us, with a given range of surface quality specification, laser tracker is an easy and reliable measurement and inspection tool to be considered.
Journal of engineering, May 13, 2022
Metal-polymer-metal (MPM) sandwich composites are in the class of pro cient engineering materials... more Metal-polymer-metal (MPM) sandwich composites are in the class of pro cient engineering materials which give outstanding strength-to-weight ratios because of their comparatively low density. ese materials are vital constituents within the automobile, aerospace, marine, and civil construction industries as substitutes for sheet metals that considerably reduce weight while not compromising functionality. Moreover, these materials have supplementary qualities like sound dampening and thermal insulation capabilities. For these materials to be utilized within the aforesaid industries, they need to bear numerous forming processes that are essential in product manufacturing. is paper investigated formability analysis of metal-polymer sandwich composites made of "AW 6082-PVC-AW 6082 (APA)" and "galvanized steel-PVC-galvanized steel (GPG)" sandwich sheets, considering epoxy structural adhesives as the binding agent, via FEA simulation. All the FEA simulations were performed using Altair HyperWorks software. For evaluating the formability, the actual limit dome height (LDH)-biaxial strain path-tests were simulated using FEM software. e results analyzed are forming limit diagram (FLD), punch force distribution, and a dome height at diverse conditions of punch velocity and friction. A comparison is made to represent the best combinations for formability of the sandwich composites. Maximum formability and dome height are attained at low friction conditions and forming speed. It has also been observed that LDH simulations are very sensitive to friction, and it has a substantial impact on the test outputs. Maximum thinning (or fracture) generally moves away from the apex of the dome towards the die corner radius as the friction increases from zero upwards.
Lecture notes on multidisciplinary industrial engineering, 2019
The current effort is intended to evaluate the forming behavior of the EN-10149-2 (S700mc) steel ... more The current effort is intended to evaluate the forming behavior of the EN-10149-2 (S700mc) steel of 2.42 mm thickness under in-plane plane-stretching (IPPS) condition at ambient conditions. EN-10149-2 (S700mc) steel has good mechanical properties and lightweight that increase the application in automotive, aerospace, and industrial structural design compared to other metals. For which, the tensile and plain stretching test samples were prepared in three rolling directions 0°, 45°, and 90°. The mechanical properties such as the yield strength, tensile strength, uniform elongation, total elongation, hardening exponent (n-value), material strength coefficient (K) and plastic strain ratio (R-value) of EN-10149-2 (S700mc) steel are evaluated from the tensile testing. The microstructure and hardness of the material were also evaluated. IPPS evaluation test has been carried out by stamping circular grids at the middle of the specimen by which measured the manor and major strain using thickness gradient necking criterion (TGNC). The obtained results from experiments found that the maximum limit strain is appeared for the rolling direction of 45° and followed by 90° and 0°. This indicates that the maximum formability is in 45° rolling direction during the IPPS test.
International Journal of Industrial and Systems Engineering, 2020
Tube hydroforming (THF) is a special manufacturing process used to produce tubular components hav... more Tube hydroforming (THF) is a special manufacturing process used to produce tubular components having applications in aerospace and automotive industries. The present study investigates the effect of process parameters such as coefficient of friction (CF), corner radius (CR) of the die and the axial feeding (AF) of the punch. The bulge ratio and thinning ratio has been evaluated to minimise the defects like bursting, wrinkling and buckling in the tubes. Apart from many parameters, these parameters are chosen to know the effect of each individual parameter on the outcomes namely bulge ratio and thinning ratio. Each factor has varied with three levels and a total of 27 simulations were carried out based on full factorial design. RSM and ANN were applied on the obtained results in order to predict the process parameters effect on the tube hydroforming process. The R-square value of ANN (0.9524 and 0.9517) is much closure to 1 when compared to R-square value of RSM (0.9539 and 0.9509).
Journal of Advanced Manufacturing Systems, Dec 1, 2020
Advanced forming technologies have been evolving at a rapid pace with the products applicability ... more Advanced forming technologies have been evolving at a rapid pace with the products applicability in the industrial fields of aerospace and automobile especially for the materials like aluminum and titanium alloys (light weight) and ultra-high strength steels. Innovative forming methods like hydroforming (tube and sheet) have been proposed for industries throughout the world. The ever-increasing needs of the automotive industry have made hydroforming technology an impetus one for the development and innovations. In this paper, the review on various developments towards lightweight materials for different applications is presented. The influencing process parameters considering the different characteristics of the tube and sheet hydroforming process have also been presented. General ideas and mechanical improvements in sheet and tube hydroforming are given late innovative work exercises. This review will help researchers and industrialists about the history, state of the art in hydroforming technologies of the lightweight materials.
Advances in Materials and Processing Technologies, Dec 28, 2019
Tube hydroforming (THF) technology is mostly used in automotive and aerospace industries because ... more Tube hydroforming (THF) technology is mostly used in automotive and aerospace industries because of its benefits like high precision, less weight and forming capability of complex shapes. Formability of the tube is the main factor for the consideration of the THF technologies in the industries. Thickness distribution in the bulged area is the key factor for the consideration of hydroformed parts. In the present paper, effects of coefficient of friction and corner radius of the die on bulge height and thickness distribution of the bulged area are studied using finite element method. Mechanical properties required to carry out the numerical simulations are evaluated by tensile, R-bar and pin-on-disc tests. Pin-on-disc experiments are carried out on the chosen material to find the wear and frictional coefficient with varying normal loads. Both numerical and analytical solutions are compared for the internal pressure required to bulge and burst the tube and observed to be in good agreement with each other. This study helps the researchers and industrialists for further understanding of the mechanics involved in the THF process in terms of die design and frictional effects.
Advances in Mechanical Engineering, Nov 1, 2022
This paper focuses on finite element (FE) modeling using a Lagrangian approach with the ABAQUS/Ex... more This paper focuses on finite element (FE) modeling using a Lagrangian approach with the ABAQUS/Explicit code to simulate the morphology of CSN 12050 carbon steel chips obtained using different tool rake and flank angles. The cutting operation was performed with a 3D model setup based on the cutting tool to determine the impact of the tool rake and flank angles on the total energy ( ETOTAL), the von Mises stresses, and the cutting force. In these simulations, using adaptive meshing for the tool, 0°, 5° and 10° rake angles, 0° and 6° flank angles, and 0.2-mm and 0.5-mm cut depths were considered as process parameters and the continuous chip morphology was predicted. The tool with 10° rake and 6° flank angles projected moderate machined surface integrity. The FE analysis tool predicted increased von Mises stresses and reduced cutting forces with the 10° rake and 6° flank angles. The maximum ETOTAL and cutting force were obtained for both cut depths when using a tool with 0° and 5° angles. Additionally, experimental results for the mechanical morphology properties of untreated, annealed and recrystallized CSN 12050 carbon steel chips showed that the predicted and experimental chip morphologies agreed well.
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Papers by Perumalla Ramulu