Car Body Structure Research Articles

Structural Optimization of Subway Aluminum Alloy Car Body Analyzed by Optistruct Software

In accordance with the life cycle cost of the vehicle, the structure of the aluminum alloy car body structure of Shanghai Line 16 was optimized based on the Optistruct software. Then the load combination conditions are divided into 9 operating conditions based on EN12663-2010. Furthermore, the optimized car body is judged whether it is qualified. The experimental results show that the optimized car body structure of Shanghai Line 16 can meet EN12663 and TB/T1335. In this paper, it provides a high application prospect for reducing LCC of the aluminum alloy car body in the design stage.

New sheet metal forming process for springback reduction by continuous stress superposition

The use of ultra-high-strength steels (UHSS) enables a lightweight and resistant design of sheet metal parts in modern car body structures. In terms of manufacturing such dedicated materials, intense springback phenomena reduce the process stability and dimensional quality. In this context, new developments in springback compensation show promising results when superimposing stresses. Therefore, this paper deals with a new approach, which modifies conventional deep drawing of open profiles by substituting the blankholder by L-shaped sliders. This allows an additional application of horizontally acting forces along the edge of the flange and leads to advantageous free buckling and rolling of the material onto lateral punch surfaces. A numerical feasibility study of this new forming method was performed in this work, showing that compressive stresses and alternate bending through buckling in fact does reduce the amount of springback remarkably compared to conventional deep drawing.

Structural Performance of Subway Aluminum Alloy Car Body Analyzed by Abaqus Software

In accordance with the structural performance shortages of the lightweight subway, the verification of the strength and stiffness of subway vehicles is proposed. Then the load combination conditions are divided into 9 operating conditions based on EN12663-2010. With the aid of Abaqus software, the strength and stiffness are judged whether it is qualified. The experimental results show that the aluminum alloy car body structure of Shanghai Line 16 can meet EN12663 and TB/T1335. In this paper, it provides a verification process for the reliability of the strength and stiffness of subway aluminum alloy car body.

Effect of Laser Pulse Duration on Tensile and Electrochemical Behavior of Laser-Welded Dual-Phase Steel

Dual-phase steels having excellent combination of strength and ductility are extensively used in automotive industry for the manufacture of car body structure involving welding and joining significantly. The present study assesses the tensile and electrochemical behavior of butt welded dual-phase 780 steel grade produced using pulsed Nd:YAG laser with varying pulse duration in the range of 1.5 to 3.6 ms. Numerical modeling has been done to know the temperature profile during welding. Systematic analysis of welded joint bead profile, microstructure, tensile test results, and fractographic features revealed the effect of pulse duration on the fusion zone, heat-affected zone softening, and also allowed the estimation of critical size of the soft zone near to the failure location under tensile loading. With an increase in pulse duration, welded joint concavity reduced from 35 to 6% which improved the mechanical performance of the welded joints. Welded joints with higher pulse duration enhanced the resistance against galvanic and pitting corrosion due to the formation of the oxide layer, finer martensitic microstructure in the fusion zone and a smaller amount of weld defects.

High strength and plasticity of AISI 430 ferritic stainless steel achieved by a recrystallization annealing before quenching and partitioning process

AISI 430 ferritic stainless steels treated by traditional bell furnace annealing exhibit good plasticity but low strength, which limits its application range. A new heat treatment process, a recrystallization annealing and quenching and partitioning (Q&P) process, was applied to AISI 430 ferritic stainless steel in this study. This type of process enabled AISI 430 ferritic stainless steel to have high strength while maintaining good plasticity. AISI 430 ferritic stainless steel can be used as a material for automobile body structures, and its application range has been greatly expanded. The Q&P860 × 5 sample had the best comprehensive performance: its strength was 730 MPa, its elongation after break was 19.4%, and its product of strength and elongation was 14.2 GPa%. After treatment by the Q&P process, the microstructure was composed of ferrite, martensite, and retained austenite. The fraction of each phase was determined, and it was observed that the fraction of retained austenite gradually increased as the recrystallization annealing temperature and time increased. M23C6 precipitates formed in both the martensite and retained austenite, and a large number of low-angle grain boundaries were also observed. The texture of the Q&P samples mainly comprised γ-texture and weak α-texture. Compared with the recrystallization annealing samples, the tensile strength of the Q&P samples was greatly improved, while the high degree of plasticity was maintained, and the yield plateau disappeared.

Design Study for Automatic Production Line of a Sub-Assemblies of New Generation Car Body Structures Compliant with the “Industry 4.0” Concept

A design study of automatic line-to-production of a new generation of car body structures compliant with the Industry 4.0 concept is described in this paper. The line is based on the hot-stamping technology of components of a car body structure from 22MnB5 steel sheets. Additional modules of the designed production line are: laser-trimming station, station to completion (kitting-up), and spot-welding station of the subassemblies. Technical requirements to be complied with by such line and scheme of exchange of information between modules of the line were defined. The conclusions were formulated.

Analysis of Automobile Body Structure and Monocoque Body Welding Technology

Is the main purpose of the car body by passenger, cargo, safely and reliably protect passengers and cargo from wind, sand, rain, snow, etc., constitute a good air mechanics environment, body should guarantee reasonable structure, beautiful shape, color coordination, and can effectively reduce the car’s fuel consumption, air resistance and ensure the car driving stability and cooling condition of the engine, ensure the car ventilation, etc. The body parts mainly include body shell, surface meal gold, freight car and cab, door, window, frame and so on. The automobile body structure can be divided into three types: non-bearing, semi-bearing and bearing. There are many kinds of welding methods commonly used in body maintenance, and it is of great significance to research and formulate the welding repair process for body.

New Design of Composite Structures Used in Automotive Engineering

The paper proposes composite materials for the manufacturing of parts of the car body structure, namely a door. This work aims to analyze the possibility of replacing the metal door of a vehicle with a door made of composite materials. Specific issues related to this replacement are analyzed in the paper. Test specimens were made of composite materials of different sizes, using several types of constituents to determine which material might be most suitable to replace metal in the manufacturing of the door. The choice of materials for the car door was made starting from the characteristics of the analyzed composite materials, but also taking into account the manufacturing possibilities and other engineering limitations. The behavior of the automotive structure as analyzed, using the finite element method for determining the stresses in the structure. Experimental verifications were performed on an experimental stand which has been specially designed for this purpose, to validate the proposed model.

ОБОСНОВАНИЕ МЕТОДИКИ АНАЛИЗА КОМФОРТА И БЕЗОПАСНОСТИ ПРИ ПЕРЕВОЗКАХ ПАССАЖИРОВ ЗА СЧЕТ УМЕНЬШЕНИЯ ВИБРАЦИОННОЙ НАГРУЖЕННОСТИ КУЗОВА ПАССАЖИРСКОГО ВАГОНА

The purpose of the work is to increase comfort and safety of railway passenger transportation, at the expense of passenger car body vibration load decrease. The analysis of the investigations carried out and dedicated to the definition of rigidity property impact upon the level of passenger comfort and traffic safety has shown that the first mode of vertical bending impacts considerably upon car body dynamic behavior. The analysis of vibration load impact upon passenger car body was carried out in accordance with Dumitriu’s technique. As apposed to the investigations carried out earlier in the paper the data on car metal structure acceleration are obtained through the methods of mathematical modeling based on solid and finite element models. 
 On the basis of the data obtained and natural running tests there was created and verified a particularized lamellar finite-element model of a car body with the aid of which there were obtained values of vertical and horizontal accelerations of a car body metal structure. The analysis of the results obtained has shown that within the frequency range of 8.9. – 20 Hz there are observed acceleration surges which are among the most sensitive ones in terms of the impact upon man and transport comfort support. 
 At the frequencies obtained there was carried out a passenger comfort investigation with the aid of which it was defined that at the frequency of car body own bending oscillations of 8.9 Hz – a comfort index is above 4 units that shows a low comfort level. 
 A frequency of 8.9 Hz corresponds to a vertical bending mode which is the most significant mode of car body deformation in terms of passenger comfort support. With regard to this in the works there was offered a number of efficient measures for strengthening car body structure bearing capacity with the goal of its bending rigidity increase which provides an installation of a supplementary bearing partition in the mid-section of a car body, and also the introduction of auxiliary longitudinal elements in a frame supporting design. For the effectiveness assessment of measures offered there was carried out re-investigation according to the technique described. As a result of the computation it was defined that the design measures offered allowed increasing a frequency value of own bending vibration of car body metal structure up to 11.7 Hz. 
 The analysis of the results obtained allowed drawing a conclusion of the effectiveness of design solutions offered on car body vibration load decrease.

Simulation Analysis of Complex Aluminium Alloy Structural Component of High-Speed Train

High-speed trains are now the most important medium- and long-distance mode of transport in many countries, and green economy is one of the important directions of high-speed train design. Aluminum alloy material is widely used in various structural parts of high-speed trains due to its advantages of high strength and low density, etc. As the speed of high-speed trains is getting faster and faster, the load on the car body structure is getting bigger and bigger, the safety, reliability and longevity of aluminum alloy structure has received wide attention. In this paper, the stress distribution, maximum stress value and maximum stress point position of aluminum alloy structural members of high-speed trains are analyzed in detail based on the real load situation, and the influence of stress level on train operation is analysed. The above work has certain reference significance for the design of high-speed train.

Research on light weight of thin-walled beam for automobile body

The developing trend of the light-weight car is the using of new light-weight materials and the optimization of the car body structure. The beam construction is the major bearing part of the car body. The thin–walled beam of the light-material plays a significant role in lightening the car' own weight, saving the materials, reducing fuel consumption and air pollution. Firstly, the relationship between the thin-walled beam that is fixed in both points and the attribute of the material can be infered from the stiffness coefficient which used as the quantitative index to estimate materials. Then take the body-in-white produced by domestic car factory as an object of study, and use Cu or Al or Mg as the materials of the thin-walled beam to calculate the bending rigidity and torsional stiffness of thewhole car body by using the FEM simulation conducted in HyperMesh.The results show that under the condition of bending and torsion, the SME value is lower when the lighten materials such as Al or Cu are used as the bodywork of the thin-walled beam than steel is. Lighten material can greatly reduce the weight of the vehicle. But it also decreased the bending and torsional stiffness of the bodywork. Therefore, in order to avoid decreasing mechanical properties which caused by adopting lighten materials, we must consider the structural design of the thin-walled beam when adopt material for lightweight.

The study and optimization of the behavior and energy absorbed in the frontal impact by a rectangular metal workpiece with an Origami core

The bumper systems (beams and face bars) are parts of the car body structure, one of the most important components of an auto vehicle because of its role in absorbing the energy of an impact by deformation. The main objective of this paper is to study, optimize the built shape of the frontal members beams used in the endurance structure of motor vehicles in terms of their ability to absorb internal energy resulting from a frontal impact under the principles of sustainability. The study combines the classical technology used in the construction of vehicles with, the Origami Engineering” technique, which is generally used by NASA, but also by engineers in other fields: aeronautics, nanotechnology or medical technique. Simulation analyses were performed using the finite element on different types of thin-walled metal tubes, but also an origami structure.

Collision test and FE analysis of actual railway carbody structure made of stainless-steel against dump truck

Collision test and FE analysis of actual railway carbody structure made of stainless-steel against dump truck

Characterization of Tensile Properties of Friction Stir Welds for Railway Carbody Structure Made of Aluminum Alloy Using Digital Image Correlation Method

Characterization of Tensile Properties of Friction Stir Welds for Railway Carbody Structure Made of Aluminum Alloy Using Digital Image Correlation Method

Control of oxide non-metallic inclusions in production of IF steel

Modern trends in the automotive industry are aimed at reducing vehicle weight and increasing its safety. The high ductility of IF-BH steel in combination with increased strength allows the use of thinner rolled products in the car body structure. Achievement of high plastic properties in IF-BH steel is ensured by the low content of nitrogen and carbon (C <40 ppm, N <40 ppm) and controlled carbon content in the solid solution. The majority of sheet surface defects are associated with non-metallic inclusions. The presence of non-metallic inclusions in the finished product violates its homogeneity, deteriorates the surface properties of steel, fatigue strength and plastic characteristics of the metal. As a result of the work performed by the methods of fractional gas and micro-X-ray spectral analysis on a scanning electron microscope, metal samples of three IF-BH steel melts were analyzed, taken along the entire process chain of production. The main types of oxide non-metallic inclusions in the steel were quantitatively determined, as well as the total oxygen and nitrogen content in the metal. It is shown that the main types of oxide non-metallic inclusions in the investigated metal samples are aluminates, silicates and spinel. An increase in nitrogen content in the metal after breakdown of the vacuum on the VD was established, which indicates secondary oxidation of the metal. In metal of the samples in the section between the tundish and the crystallizer, nitrogen content in the metal increases which indicates the secondary metal oxidation. At the same time, the content of inclusions of aluminates in the metal increased and the number of inclusions of aluminum-magnesium spinel decreased. A mathematical model and software have been developed that describe the formation and removal of oxide nonmetallic inclusions. Adequacy of the program was confirmed by good convergence between the calculated and laboratory data on the total content [O] in various types of oxides for the first sample at the ladle-furnace unit and in the slab.

PERANCANGAN DAN ANALISIS CARBODY LOKOMOTIF DENGAN METODE ELEMEN HINGGA

A locomotive is one of critical part in train set, because a locomotive had to bear a big load and has operational time which long enough. So in a locomotive design required more in depth analysis compared to the other means of transportation. The purpose of this research is to make a design locomotive carbody according to those standards applied and analyze stress happened to carbody locomotive designed. In the design of this to analyze carbody locomotive construction strength, the analysis are done using finite element methode(FEM) with help of Ansys software. The simulation of loads working on the structure was made approaching the real loading. Structure of locomotive carbody should be able to hold the loads working on carbody construction. From the design results locomotive carbody that have been made, this locomotive carbody sized length 19000 mm, width 2790 mm, and high 3700 mm. Materials that used for the locomotive carbody design isSS 400 and SM 490A with Yield stress of 245 MPa dan 325 MPa. The analysis results received a value of von mises stress maximum of 195,429 MPa that occurs at the part of the end of underframe (end center sill), where the sress value are still below of Yield stress materials which are in the form of SM 490 at 325 MPa. From the analysis result suggests that overall locomotive carbody structure can be expressed as safe and able to hold the loads operational.

Study on application of MSOT method for lightweight design of automobile body structure

In this study, the integrated MSOT (M-Multi-dimensional factor autobody model, S-Screening autobody component, O-Optimization of plate thickness, T-Testing, and validation) integration method is adopted to optimize the automobile body structure design for weight reduction. First, a multi-dimensional factor body model is established, then components of the vehicle are screened for the most important targets related to weight reduction and performance, and a multi-objective optimization is performed. Virtual experiments were carried out to validate the analysis and the MSOT method were proposed for lightweight design of the automobile body structure. A multi-dimensional performance model that considers stiffness, modality, strength, frontal offset collision, and side collision of a domestic passenger car body structure. Components affecting the weight of the vehicle were identified. Sheet metal thickness was selected as the main optimization target and a multi-objective optimization was carried out. Finally, simulations were performed on the body structure. The comprehensive performance, in terms of fatigue strength, frontal offset collision safety, and side collision safety, was verified using the optimized Pareto solution set. The results show that the established MSOT method can be used to comprehensively explore the weight reduction of the body structure, shorten the development process, and reduce development costs.

Experimental methods to capture curing induced effects in adhesive bonded joints

The rapidly increasing use of structural adhesives, especially in the joining of automotive body structures has motivated various investigations of the effects of adhesive curing process on joints. The automotive-grade structural adhesives require heat curing, which, in the meantime, performs thermal loading on the substrates and causes undesirable effects in the joint. For example, the curing process results in complex residual stresses in the adhesive bond which are detrimental to the performance of the adhesive bond and thereby the automobile body structure, particularly the crashworthiness. To thoroughly evaluate such effects, this paper consists of two parts. The first part presents an innovative experimental method to characterize the thermal effects of the heat curing process on a multi-material single lap shear joint using digital image correlation. The second part of the study compares the performance of residual stress-induced joints against stress-free joints under tension loading at different strain rates. The proposed experimental method and the corresponding results from this study are expected to help comprehensively understand the adhesive joining process and its potential side effects on the automobile body structure.

Temperature-dependent interlaminar shear strength of unidirectional continuous fiber-reinforced thermoplastic profiles

Fiber-reinforced thermoplastic composites offer a high potential for high-volume car body structures. A tailored use of thermoformed and subsequently injection overmolded unidirectional pultruded material in the so-called “skeleton design” is a promising approach towards economical lightweight design.The paper investigates the interlaminar shear strength of pultruded specimens for polyamide 6 and polypropylene as matrices at various temperature degrees. The specimens are made of different ratios of glass and carbon fibers. The results are compared to tape-laid specimens of the same materials to show the influence of the manufacturing technology. The performance is tested using a compression shear device at three testing temperatures −35 °C, +23 °C and +85 °C covering the typical temperature range for automobile structures as well as in conditioned and dry state.The interlaminar shear strength decreases on average by 65% from −35 °C to +85 °C, whereas conditioning reduces interlaminar shear strength by 25% at −35 °C and +23 °C with no influence at −35 °C.The results are analytically described in order to obtain a continuous description of the interlaminar shear strength within the analyzed temperature range.

Improvements in passenger car body for higher stability of train ferry

The authors suggest that the strength of passenger car bodies under train ferry transportation can be provided by mounting fastening elements of chain binders on the body bolster beams. The principle of such an element is based on the hydraulic damper operation Therefore, the authors developed a mathematical model which considered displacements of a train ferry loaded with passenger cars under rolling motion. The model was solved in Mathcad software. The mathematic modeling was conducted in order to determine the dynamic loading on a passenger car body under sea transportation. The study established that the improvements mentioned made it possible to reduce the dynamic loading on the body under sea transportation by 30% in comparison with that of a typical fastening scheme. The strength of an improved passenger car body was calculated. The maximum equivalent stresses in the body structure accounted for about 120 MPa, i.e., they did not exceed the admissible values. Besides, the study presents the computer modelling of dynamic loads of the carrying structure of a passenger car body under train ferry transportation. Numerical values of the accelerations and their distribution fields relative to the carrying structure of a car were determined. The adequacy of the designed models was checked with an F-test. The research and proposed engineering solutions can ensure the adequate strength of passenger car bodies under their transportation by train ferries, and also conduct efficient international rail/ferry transportation.