Table of Content

25 March 2015, Volume 3 Issue 1

Previous Issue    Next Issue

Guest editorial of "Application of high strength steels in lightweight commercial vehicles"

H. Mohrbacher

2015, 3(1):  1-2.  doi:10.1007/s40436-015-0098-1

Asbtract ( 788 )   PDF (156KB) ( 289 )  

Related Articles | Metrics

Innovative manufacturing technology enabling light weighting with steel in commercial vehicles

Hardy Mohrbacher, Marius Spöttl, Jesse Paegle

2015, 3(1):  3-18.  doi:10.1007/s40436-015-0101-x

Asbtract ( 820 )   PDF (3819KB) ( 1596 )  

References | Related Articles | Metrics

Improved manufacturing technology is often needed when working with high strength steel. In this respect manufacturing technology has to adapt to the altered (and typically reduced) formability and weldability of modern high strength steel. However, this is a rather passive approach from a manufacturing point of view. An indeed much more powerful approach is to generate synergies between innovative manufacturing technology, design and material enabling additional weight savings and efficiency gains. Laser-based material processing, in particular laser welding, offers a wide range of opportunities in this sense. Furthermore, hot stamping and roll forming open up new possibilities for advanced manufacturing of commercial vehicle components. Applications and examples of these technologies will be given in terms of producing innovative semi-products as well as final components.

Light weighting opportunities and material choice for commercial vehicle frame structures from a design point of view

Peter Seyfried, Ed Juarez Mendes Taiss, Alexandre Costa Calijorne, Fei-Peng Li, Qi-Feng Song

2015, 3(1):  19-26.  doi:10.1007/s40436-015-0103-8

Asbtract ( 731 )   PDF (906KB) ( 633 )  

References | Related Articles | Metrics

This paper focuses on an estimation of light weighting opportunities for the frame structure of commercial road vehicles. This estimation is based on simplified static load cases which play a predominant role for the dimensioning of a frame structure and therefore these simplifications are not putting the general validity of the conclusions into question. A comparison of different materials under this scenario shows that light metals do not show any weight reduction advantage in comparison to steel while a material-independent topology optimization has more weight reduction potential for the frame structure than a simple change of materials. Considering the constraints of part complexity which is directly linked with production and assembly cost, the ladder frame structure has become the current state of the art design. Thus the paper also puts a spotlight on basic rules of node design and vertical load induction in order to keep the weight of such a design as low as possible. Practical examples from manufacturers show that the weight of a commercial vehicle could be reduced by 10% and main parts of the frame structure could be reduced by 30% using high strength steel in combination with innovative production methods like roll forming.

Application potential of high performance steels for weight reduction and efficiency increase in commercial vehicles

Jian Bian, Hardy Mohrbacher, Jian-Su Zhang, Yun-Tang Zhao, Hong-Zhou Lu, Han Dong

2015, 3(1):  27-36.  doi:10.1007/s40436-015-0102-9

Asbtract ( 675 )   PDF (2716KB) ( 496 )  

References | Related Articles | Metrics

The fast-growing economy and the gradually established highway system have boosted the road transportation for both passenger and cargo over the last decade in China. From 2000 to 2010 Chinese GDP increased by around 10.15% annually and the sales of medium and heavy trucks by around 18.87% (sales increased from 0.2 million in 2000 to 1.3 million in 2010) according to the National Bureau of Statistics of People's Republic of China. Today commercial vehicles consume almost the same amount of fuel as passenger cars in China although the number of commercial vehicles is only about one fourth of passenger cars. It is estimated that around 50% of imported fuel to China each year will be consumed by vehicle transportation. This situation will worsen fuel shortage problems in the long run and at the same time it is partially responsible for the everworsening air pollution in China. Due to the widespread overloading in China, lightweight development in commercial vehicles has fallen far behind that of passenger cars with the consequences that Chinese commercial vehicles consume in average about 20% more fuel, especially the heavy trucks, compared to European models. Under these circumstances it is essential to reduce the vehicle fuel consumption and increase the transport efficiency. The key solution thereby is to implement lightweight design in commercial vehicles as it has been successfully practiced over the last decade in the passenger cars. This paper summarizes highlights given in presentations during the "International seminar on the application of high strength steels in light weight commercial vehicles" with the focus on the development and application of Nb alloyed high performance steels made for lightweight commercial vehicles.

Sustainable development of China's commercial vehicles

Li-Gang Wang, Ning Zhang

2015, 3(1):  37-41.  doi:10.1007/s40436-015-0104-7

Asbtract ( 792 )   PDF (573KB) ( 657 )  

References | Related Articles | Metrics

Automobiles are the major contributor to fuel consumption and emission of pollutants. The growth of the vehicle fleet has also placed enormous pressure on China's energy supply and environment. Thus sustainable development of the Chinese automotive industry must pay significant attention to fuel-saving and emission-reduction of vehicles. Although commercial vehicles make up only about 20% of the entire automobile fleet, their contribution to energy-consumption and emission of pollutants is significant. Thus, priority should be given to fuel-saving and emission-reduction of commercial vehicles. As a result of concerted efforts by Chinese government, industry and enterprises, great progress has been made in technologies concerning new-energy, intelligent and lightweight automobiles. However, compared with developed countries, the level of lightweighting of commercial vehicles produced in China remains comparably low. This means that great potential for development of lightweight commercial vehicles in China exists and it will be an efficient path towards fuel-saving and emission-reduction.

Optimization of fused deposition modeling process parameters: a review of current research and future prospects

Omar A. Mohamed, Syed H. Masood, Jahar L. Bhowmik

2015, 3(1):  42-53.  doi:10.1007/s40436-014-0097-7

Asbtract ( 4723 )   PDF (900KB) ( 4356 )  

References | Related Articles | Metrics

Fused deposition modeling (FDM) is one of the most popular additive manufacturing technologies for various engineering applications. FDM process has been introduced commercially in early 1990s by Stratasys Inc., USA. The quality of FDM processed parts mainly depends on careful selection of process variables. Thus, identification of the FDM process parameters that significantly affect the quality of FDM processed parts is important. In recent years, researchers have explored a number of ways to improve the mechanical properties and part quality using various experimental design techniques and concepts. This article aims to review the research carried out so far in determining and optimizing the process parameters of the FDM process. Several statistical designs of experiments and optimization techniques used for the determination of optimum process parameters have been examined. The trends for future FDM research in this area are described.

Finite element modeling of chip separation in machining cellular metals

R. Guerra Silva, U. Teicher, A. Nestler, A. Brosius

2015, 3(1):  54-62.  doi:10.1007/s40436-015-0099-0

Asbtract ( 953 )   PDF (1217KB) ( 1182 )  

References | Related Articles | Metrics

Cellular metals and metal foams belong to a young material group. Although it is desired to manufacture near-net-shape parts of cellular metals by primary shaping processes, additional secondary machining operations are often unavoidable to obtain the required geometries and quality demands. Nevertheless, conventional machining of cellular metals leads to undesirable surface damage and poor precision. Furthermore, the chip formation and the mechanism description of the surface damage are still unclear. A mesoscopic finite element model was developed to simulate the chip formation process in machining cellular metals. Experimental data of orthogonal machining tests were used to validate the finite element model. The cutting and thrust forces, as well as the images of the chip formation process of both experiments and simulations were compared and analysed. The model enabled the analysis of the chip formation and the surface defect mechanisms. The rake angle and cutting conditions affected the chip formation process, but the cell arrangement was detected as a decisive factor in the chip formation and the resulting surface damage.

Emerging carbon-based nanosensor devices: structures, functions and applications

S. Manzetti, D. Vasilache, E. Francesco

2015, 3(1):  63-72.  doi:10.1007/s40436-015-0100-y

Asbtract ( 716 )   PDF (862KB) ( 1548 )  

References | Related Articles | Metrics

Bionanosensors and nanosensors have been devised in recent years with the use of various materials including carbon-based nanomaterials, for applications in diagnostics, environmental science and microelectronics. Carbon-based materials are critical for sensing applications, as they have physical and electronic properties which facilitate the detection of substances in solutions, gaseous compounds and pollutants through their conductive properties and resonance-frequency transmission capacities. In this review, a series of recent studies of carbon nanotubes (CNTs) based nanosensors and optical systems are reported, with emphasis on biochemical, chemical and environmental detection. This study also encompasses a background and description of the various properties of the nanomaterials, and the operation mechanism of the manufactured nanosensors. The use of computational chemistry is applied in describing the electronic properties and molecular events of the included nanomaterials during operation. This review shows that resonance-based sensing technologies reach detection limits for gases, such as ammonia down to 10^-24 level. The study also shows that the properties of the carbon nanomaterials give them unique features that are critical for designing new sensors based on electrocatalysis and other reactive detection mechanisms. Several research fields can benefit from the described emerging technologies, such as areas of research in environmental monitoring, rapid-on site diagnostics, in situ analyses, and blood and urine sampling in medical and sport industry. Carbon nanomaterials are critical for the operational sensitivity of nanosensors. Considering the low cost of fabrication, carbon nanomaterials can represent an essential step in the manufacturing of tomorrow's commercial sensors.

Double regularization control based on level set evolution for tablet packaging image segmentation

Li Liu, Ao-Lei Yang, Xiao-Wei Tu, Wen-Ju Zhou, Min-Rui Fei, Jun Yue

2015, 3(1):  73-83.  doi:10.1007/s40436-015-0105-6

Asbtract ( 701 )   PDF (6510KB) ( 797 )  

References | Related Articles | Metrics

This paper proposes a novel double regularization control (DRC) method which is used for tablet packaging image segmentation. Since the intensities of tablet packaging images are inhomogenous, it is difficult to make image segmentation. Compared to methods based on level set, the proposed DRC method has some advantages for tablet packaging image segmentation. The local regional control term and the rectangle initialization contour are first employed in this method to quickly segment uneven grayscale images and accelerate the curve evolution rate. Gaussian filter operator and the convolution calculation are then adopted to remove the effects of texture noises in image segmentation. The developed penalty energy function, as regularization term, increases the constrained conditions based on the gradient flow conditions. Since the potential function is embedded into the level set of evolution equations and the image contour evolutions are bilaterally extended, the proposed method further improves the accuracy of image contours. Experimental studies show that the DRC method greatly improves the computational efficiency and numerical accuracy, and achieves better results for image contour segmentation compared to other level set methods.

Modeling and multi-response optimization of machining performance while turning hardened steel with self-propelled rotary tool

Thella Babu Rao, A. Gopala Krishna, Ramesh Kumar Katta, Konjeti Rama Krishna

2015, 3(1):  84-95.  doi:10.1007/s40436-014-0092-z

Asbtract ( 682 )   PDF (1679KB) ( 1061 )  

References | Related Articles | Metrics

There are many advanced tooling approaches in metal cutting to enhance the cutting tool performance for machining hard-to-cut materials. The self propelled rotary tool (SPRT) is one of the novel approaches to improve the cutting tool performance by providing cutting edge in the form of a disk, which rotates about its principal axis and provides a rest period for the cutting edge to cool and allow engaging a fresh cutting edge with the work piece. This paper aimed to present the cutting performance of SPRT while turning hardened EN24 steel and optimize the machining conditions. Surface roughness (R_a) and metal removal rate (^rMMR) are considered as machining performance parameters to evaluate, while the horizontal inclination angle of the SPRT, depth of cut, feed rate and spindle speed are considered as process variables. Initially, design of experiments (DOEs) is employed to minimize the number of experiments. For each set of chosen process variables, the machining experiments are conducted on computer numerical control (CNC) lathe to measure the machining responses. Then, the response surface methodology (RSM) is used to establish quantitative relationships for the output responses in terms of the input variables. Analysis of variance (ANOVA) is used to check the adequacy of the model. The influence of input variables on the output responses is also determined. Consequently, these models are formulated as a multi-response optimization problem to minimize the R_a and maximize the rMMR simultaneously. Non-dominated sorting genetic algorithm-II (NSGA-II) is used to derive the set of Pareto-optimal solutions. The optimal results obtained through the proposed methodology are also compared with the results of validation experimental runs and good correlation is found between them.