bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accessible pedestrian paths for educational setting design evaluation: Case study in Surabaya and Bandung City, Indonesia and Brisbane City, Australia
Authors: Tallar Robby Yussac , Tanuwidjaja Gunawan , Widjaya Joyce Martha , Razafimahefa Rina 
Published: June 2023

Abstract
Covid-19 has changed the city and human lives, especially related to walking. The lockdowns in several countries such as China, Japan and Australia have prescribed urban residents to stay within approximately five to ten kilometres radius of their homes. The lockdowns were found helpful in suppressing the Covid-19 spread at a local level. However, more discussions are needed on the well-being and health of residents during a hard time. In Australia, two people could exercise during lockdowns for one hour within the resident’s neighbourhoods. The needs for accessible pedestrian paths in the neighbourhood are essential during Covid-19. Some universities were closed during the lockdowns in the educational sector, but students could stay near the campus and use facilities within. Many students need accessible pedestrian paths to walk to the campus from their apartments and shopping centres. This lockdown further generates the idea to research pedestrian paths’ accessibilities in some educational context in Surabaya, Bandung, both in Indonesia and Brisbane, Australia. The simple access evaluations are conducted with photography documentation and simple measurement based on ADAAG 2010 and local regulations. Therefore, the pedestrian paths in two locations in Indonesia are found to be less accessible, while pedestrian paths in Brisbane are found to be more accessible. The less accessible Indonesian pedestrian paths are caused by a lack of spaces, poor construction, and pedestrian paths’ poor management. Meanwhile, better access standards, better infrastructure management, and proper construction are essential key points for better accessible pedestrian paths.
Effect of bed shear stress on the mobile armor layer at the riverbed
Authors: Negara Arlendenovega S , Ikhsan Cahyono , Hadiani Rr. Rintis , Purwana Yusep M 
Published: June 2023

Abstract
Armoring is forming an armor layer of the riverbed which is preceded by the transportation of bed sediment. Mobile armor occurs when the riverbed reaches equilibrium, then eroded, and the surface of the riverbed recovers. Therefore, protection is formed by moving riverbed material. This research used a simulation model generated through HEC RAS software version 6.1. The model input location was Krasak River, Sleman, Yogyakarta. The data for model input were the topography of the Krasak River from upstream to the point of view, flood discharge hydrograph, and grain size gradations. The simulation combination consisted of three locations with the riverbed material of each location sampled tested for grain size distribution. The running simulations combined the flood discharge at return periods of 2, 5, 10, 25, 50, and 100 years. There were three variations of grain size distribution used as input data. Meanwhile, variations of sediment transport methods used the Meyer-Peter Muller and Wilcock-Crowe methods. Overall, the simulation results show that the shear stress and the proportion of sand-to-grain material affect the armoring process and riverbed changes.
A mechanical interlocking joint between sheet metal and carbon fibre reinforced polymers through punching
Authors: Latorre Núria , Casellas Daniel , Costa Josep 
Published: June 2023

Abstract
The joint between different lightweight materials plays a significant role in multi-material design of structural components for the automotive industry, aiming to reduce the vehicle’s weight without compromising performance or safety. Yet, conventional mechanical joining technologies between metals and Carbon Fibre Reinforced Polymers (CFRP) result in either a hole being drilled in the composite material, leading to damages which reduce the load bearing capacity, or the weight of the part being increased due to the incorporation of fasteners. At the same time, alternative mechanical joining methodologies involve complex and costly processing, hindering their industrial application. This work presents a new, simple, cost-efficient and non-weight penalizing mechanical joining technology between a metal sheet and fibre reinforced polymer prepregs consisting of a single-step punching process. In this process, the metallic sheet is completely perforated, while the prepreg is not. The punch pushes the carbon fibres through the metallic hole, with no, or minimal fibre breakage, generating a mechanical interlock. The shear strength and the absorbed energy of the co-cured joint increase with the incorporation of the mechanical interlocking joint.
Analysis of process limits for partial hot stamping with controlled pre-cooling by radiation exchange
Authors: Reihani A , Donat L , Heibel S , Schweiker T , Gienger M , Güner A , Winderlich M , Merklein M 
Published: June 2023

Abstract
The increasing demands on part complexity and tailored properties in form of local strength and ductility cannot be achieved with conventionally manufactured hot stamped body components. To meet the requirements of safety-relevant body parts, partial hot stamping is increasingly used in the automotive industry. One approach to achieve tailored properties on hot stamped parts is based on controlled cooling of the blank prior to forming and quenching. The related furnace technology is based on a furnace chamber in which a cooled aluminum mask protects local areas of the blank from thermal radiation while simultaneously absorbing the blank’s own emitted radiation. The sheet thickness and utilized material significantly influence the controlled radiation exchange and present potential process limits. To analyse these lower process limits, blanks made of the materials 22MnB5 AS150 and 8MnB7 AS150 are partially pre-cooled and hot stamped with different sheet thicknesses. In addition, the process is simulated with AutoForm®R10 and validated by the obtained experimental results. The results show that the sheet thickness is a key influencing factor in the process and significantly affects the mechanical properties after partial hot stamping. Especially sheet thicknesses t0 of 2.25 mm can limit the process, as the effectiveness of the radiation exchange for controlled pre-cooling and phase transformation decreases.
Oxygen-free resistance heating with nitrogen and silane as an energy-efficient heating process for hot stamping
Authors: Behrens B-A , Hübner S , Holländer U , Langohr A , Albracht L , Faramand E , Wehmeyer J , Yarcu S , Raumel S , Wurz M C 
Published: June 2023

Abstract
Hot stamping is a process for the production of ultra-high-strength components used in the automotive industry for passenger protection. In this process, cut blanks are heated in a roller hearth furnace, which is operated with gas, to approx. 950 °C in 8 to 10 min and then formed and quenched in a water-cooled tool. This extends the yield strength of the components up to 1500 MPa. The long heating time is caused by the coating of aluminium and silicon (AlSi) with a thickness of 70 μm. During the 8 to 10 min, an intermetallic phase forms and ensures that the blank does not scale. Due to the long heating time and the energy carrier gas, the process is very energy inefficient and can only be controlled slowly. Resistance heating provides an energy-efficient alternative. Due to the direct current flow through the sheet, up to 68% of the energy can be saved compared to roller hearth furnace heating. The process is a high-speed heating process that can heat sheets to 950 °C in less than 10 seconds. The heating time is not sufficient for conventional coatings to bond sufficiently with the base material, which means that there are currently no suitable coatings for resistance rapid heating. A new approach is to suppress scale formation by reducing the oxygen during heating. By lowering the oxygen partial pressure to the XHV level, scale formation is not possible. At the same time, this absence of oxygen is an ideal condition for applying coatings. Due to the developed resistance heating device, sheets can be heated within a very short time without scale and without the need for fossil fuels.
Study of Microstructural Evolution of Press Hardening Steels using Dilatometer and In-situ Studies for a Simulated Hot Stamping Condition
Authors: Zhu Hong , Yin Hongbin , Sadagopan Sriram 
Published: June 2023

Abstract
Press hardening grades are widely used in automotive industries for safety-critical structural parts due to their unique combination of high strength, excellent formability, and crash performance. Considering various scenarios on thermo-mechanical profiles in different hot stamping lines, achieving the targeted strength and ductility / fracture strain in the hot-stamped parts is still challenging to some hot stampers for some grades. In this investigation, a dilatometer study for Usibor®1500 and two emerging grades Usibor®2000 and Ductibor®1000 under a given hot stamping condition was conducted with consideration of the entire hot-stamping processes (i.e., austenitization, blank transfer, forming and final quenching from 700°C) to understand the differences in critical cooling rates, and evolution of microstructures. Influence of large forming strain (15%) on final properties is also examined for Ductibor®1000 and Ductibor®500 by DIL 805 A/D dilatometer under tensile deformation mode. In-situ observation of microstructural evolution during hot stamping process for Usibor®1500 is explored using Confocal scanning laser microscope to uncover some physical phenomena for further refinement of hot stamping practices.
Development of rapid die cooling technology using the Groove Pressing method in hot stamping process
Authors: Park J M , Park K J , Kong J Y , Yoon S C , Rhee J H , Hyun J S 
Published: June 2023

Abstract
The demand for hot stamping parts in the automobile industry is increasing due to the growth of eco-friendly vehicles with improved crash safety performance and lighter weight. However, the use of ultra-high-strength steel in cold stamping is challenging due to its high yield strength and low elongation. Hot stamping is a widely used process to overcome this challenge, but the long die quenching time reduces its productivity. In order to address this issue, a Groove Pressing method was applied to the sidewall of the die to improve cooling performance without requiring additional devices within the die. The study investigated the required contact pressure between the sheet and the die for the implementation of the groove shape on the sidewall. Computational analysis was performed to design optimal groove shape for the sidewall, and the results showed that Case 3 was the most suitable in terms of cooling performance and contact pressure. The groove shape was incorporated into the die making, and experiments were conducted on aluminized coated 22MnB5 1.2 mm sheet. The results showed that the implementation of the groove shape on the sidewall improved cooling performance, dimensional quality, and mechanical properties without affecting the corrosion resistance of the component. The study demonstrates the potential of the Groove Pressing method as a practical solution for improving the productivity of the hot stamping process in the automobile industry.
Industrial Internet of Things and Big Data Techniques for the Smart Press Shop 4.0 Development in Automotive Industry
Authors: Peinado-Asensi Ivan , Montés N , García E 
Published: June 2023

Abstract
In recent years, one of the main challenges in industry has been to obtain work parameters in real time for later analysis to understand the process better. The purpose is to obtain substantial information about the process for better decision-making and to find out what happens during manufacturing to know both the state of the equipment and the product, looking for savings in maintenance costs and quality controls among others. This has not been an exception for the automotive industry. These challenges have been associated with the concept of Industry 4.0, specifically with Big Data and IIoT (Industrial Internet of Things) techniques. Following this concept, many of the companies and research teams develop their algorithms and ideas based on the installation of new sensors without taking into account the implications that this proposal has in real factories. The cost of the sensor, the installation setup, maintenance, machine modifications and replication for hundreds of machines make many of the ideas fail when innovation is implemented in the companies. For that reason, in our previous work we have introduced a novel concept in Industry 4.0, the development of algorithms by using exclusively the information that is available in the equipment. Machines, as well as presses and general automated systems, include sensors for their automated normal production. These sensors are installed and the information they provide is almost free. Following this philosophy, the present paper proposes the Criterion-360 for real press shops. With this criterion, it is possible to measure a lot of variables with no cost, not only the tonnage, but also, many variables such as the press speed, Counterbalance and overload pressure, Cushion Pressure & Position, lubrication, etc., and therefore with this amount of information many possibilities arise. As the new developed system does not need new sensors and additional installation setup, it is easy and cheap to replicate it in other presses and plants.
This article presents two tools that have been developed from the information obtained with this criterion, these tools are currently in operation and have been used to modify work processes and get the press to work in optimal conditions.
Process Monitoring using Digital Twin-Based Sensors integrated in Tool Clamping Surfaces
Authors: Kurth Robin , Alaluss Mohaned , Wagner Martin , Tehel Robert , Riemer Matthias , Ihlenfeldt Steffen 
Published: June 2023

Abstract
Process monitoring in forming technology can serve as a basis for transparent manufacturing and closed-loop control systems. Particularly, sensor systems associated with tool clamping interfaces offer great potential for robust inline process monitoring but are hardly investigated. In this paper, a concept to monitor a sheet metal forming process combined with a digital twin-based approach for virtual sensors is introduced. Here, sensors integrated into the T-slots of tool clamping surfaces in forming machines are enhanced by a mathematical representation of the elasto-mechanical behavior of the tool clamping interfaces. Moreover, the potential of the certain sensor system for inline process monitoring is highlighted. The resulting approach is substantiated by simulative analysis and by experimental investigation.
Effect of pre-strain on edge formability of high strength steels for chassis applications
Authors: Payà A , Lara A , Frómeta D , Marés M , Gil I , Arenillas C 
Published: June 2023

Abstract
There is a high level of uncertainty in the prediction of edge cracking during the design and manufacturing of high strength sheet metal products. Edge ductility is a complex parameter to measure since it is not an intrinsic property of the material, but it also depends on the trimming strategy/parameters that have been applied to the edge (edge preparation method, cutting/punching clearance, etc.). Furthermore, most forming processes involve more than one operation where the material can be deformed in a first stage, then trimmed or punched and further deformed in a final forming step to obtain the desired shape. Therefore, in order to design a robust and safe forming process able to predict the risk of edge cracking, it is crucial to understand the influence of pre-strain on the residual formability of trimmed edges. This paper analyses the effect of different pre-strain levels and paths (uniaxial tension, plane strain and equi-biaxial stretching) on the sheared edge ductility of a Complex Phase (CP) steel and a high strength low alloy (HSLA) steel used for automobile chassis applications. To this purpose, rectangular specimens are cut out from pre-strained samples and punched. Hole Tension Tests (HTTs) in combination with Digital Image Correlation (DIC) are carried out to determine the edge fracture strain of undeformed and pre-strained samples. The results are discussed in terms of major strains obtained from DIC. The proposed methodology allows describing the edge cracking sensitivity of high-strength steel sheets as a function of the pre-deformation state and can be useful to predict the risk of edge cracking more accurately in forming simulations.
Hot-forming of a 980 MPa third generation advanced high strength steel
Authors: Midawi Abdelbaset R H , Tolton C , George R , Subramanian M , Skszek T , Butcher C , Worswick M 
Published: June 2023

Abstract
This paper considers the effect of processing route on the final microstructure hardness and tensile behavior of a 980 MPa third generation advanced high strength steel (3G-AHSS). Of particular interest is the use of a hot stamping thermal schedule that mimics a quench and partition (Q&P) heat treatment process normally used to produce Q&P grade steel sheet. For comparison purposes, samples were also produced using a quench and temper (Q&T) processing history. The experiments were performed using a Gleeble 3500 thermo-mechanical simulator system. Large coupons were produced using both processing routes from which microstructure, hardness, and tensile samples were extracted. Mechanical properties results were compared with the as-received material. Both processing routes resulted in strength levels that were close to that of the as-received material; however, the total elongation of the Q&P processed samples was 52% higher than that of the Q&T processed material.
Crashworthiness evaluation of press hardened steels with different lath-like microstructures.
Authors: Aroca V P , Philippot C , Pujante J , Frómeta D , Caballero F G , Capdevila C 
Published: June 2023

Abstract
The deployment of Press Hardened Steels (PHSs) in the Body-In-White structures that took place during the two last decades is at the origin of a breakthrough weight saving on vehicles while guaranteeing the safety requirements of the automotive industry. The production of parts with complex shapes and a high strength between 1500-2000MPa was made possible by taking advantage of the hot rheology of austenite combined with the fast cooling obtained by in-die quenching leading to auto-tempered martensitic microstructures. In the present work, PHS1500 was hot stamped with different thermomechanical processes to promote different lath-like microstructures (bainite, tempered martensite…). An innovative approach is proposed to link the complex microstructures formed between thermoregulated dies to the mechanical behaviour and local ductility of these materials during crash-like solicitations. The microstructure has been characterised through a multi-characterization technique approach including light optical microscopy, scanning electron microscopy and X-ray diffraction. The local ductility is assessed with a combination of crack initiation tests (bending, notch tensile test) and crack propagation resistance tests (Essential work of fracture). Despite similar microstructural crystallographic features, lower bainite and auto-tempered martensite can lead to very different strength – local ductility compromise.
Research on toolpath optimization of robot-assisted incremental flanging
Authors: Cheng X , Zhao Y X , Yu Z Q , Chen W 
Published: June 2023

Abstract
Robot-assisted incremental flanging (RAIF), a cost-effective and promising forming technology for producing large-size open-edge flanged parts in multi-variety and small batches, is expected to be widely used in aerospace, automotive and other technological industries. As a multi-pass incremental forming technique, the forming quality of the flanged parts is dependent on the movement of the roller controlled by the robot directly. The toolpath of a certain pass is determined by the rotation velocity (to adjust the flanging angle), the revolution velocity (to complete the flanging process of the whole blank sheet) and the matching relationship between two velocities (synchronously or asynchronously). In this paper, the process principle of RAIF technology is illustrated by using the example of shrink flanging firstly, then the effects of asynchronous motion and synchronous motion on the forming quality of a 60° flanged part made of the 5A06 aluminum alloy are compared while the rotation and revolution velocity of the roller are set to 1°/s and 1.8°/s, respectively. Results show that the forming quality is improved significantly that the maximum height of edge waves is decreased from 2.1 mm to 0.19 mm when the roller is set to rotate and revolve synchronously. Based on the above comparison results, the rotation velocity is set as 1°/s, 1.33°/s, 2°/s and 4°/s respectively to further investigate the effect of different toolpaths on the forming quality under synchronous motion conditions. It can be found that the maximum stress gradually increases from 575.4 MPa to 621.6 MPa when the rotation velocity decreases from 4°/s to 1°/s.
Evaluation of hardening laws coupled with shear modified Lemaitre damage model for fracture prediction in incremental sheet forming
Authors: Kumar Abhishek , Narasimhan K 
Published: June 2023

Abstract
Incremental sheet forming (ISF) is an emerging technology for manufacturing sheet metal components with fewer tools and equipment compared to conventional sheet forming. In this process, forming is generally performed without dies and punches and a simple hemispherical shaped tool can be used for shaping the final component. Forming limit in incremental sheet forming can be defined by the maximum formable wall angle. Finite element analysis can be used for fracture prediction by using a damage model. Also, to define the material flow behaviour hardening law should be incorporated into the finite element model. In this study four different hardening laws were used with shear modified Lemaitre damage model for fracture prediction during ISF of AA1050 alloy. The effectiveness of Hollomon, Johnson-Cook, Ludwigson and Swift hardening laws were compared for fracture prediction. Further, the predicted fracture wall angles were compared with the experimental observations. The results were analysed in terms of damage and strain evolution for the predicted fracture wall angles based on different hardening models.