Technical Paper collections have been re-named for better clarity and alignment.x

Your Selections

Joining
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Committees

Events

Magazine

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Research on Joining High Pressure Die Casting Parts by Self-Pierce Riveting (SPR) using Ring-Groove Die Comparing to Heat Treatment Method

Bollhoff Inc.-Xuzhe Zhao
Chang’an University-Dean Meng
  • Technical Paper
  • 2020-01-0222
To be published on 2020-04-14 by SAE International in United States
Nowadays, the increasing number of structural high pressure die casting (HPDC) aluminum parts need to be joined with high strength steel (HSS) parts in order to reduce the weight of vehicle for fuel-economy considerations. Self-Pierce Riveting (SPR) has become one of the strongest mechanical joining solutions used in automotive industry for the past several decades. Joining HPDC parts with HSS parts can potentially cause joint quality issues, such as joint button cracks, low corrosion resistance and low joint strength. The appropriate heat treatment will be suggested to improve SPR joint quality in terms of crack reduction. But the heat treatment can also result in the blister issue and extra time and cost consumption for HPDC parts. The relationship between the microstructure of HPDC material before and after heat treatment with the joint quality is going to be investigated and discussed for interpretation of cracks initiation and propagation during riveting. The SPR joint quality will be evaluated based on interlock distance, the minimum remaining thickness (Tmin), shear strength etc. Instead of using heat treatment method, the…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

User Defined FE Based Connector Joints For Plastics

CAEfatigue Ltd-Neil Bishop, Paresh Murthy
Hella GmbH & Co. KGaA-Thomas Thesing, Odo Karger
  • Technical Paper
  • 2020-01-0186
To be published on 2020-04-14 by SAE International in United States
Spot Welds are a category of joints used extensively in automotive structures, normally for metals. The fatigue analysis of such spot welds can be evaluated using (a) the Point 2 Point (P2P) method where a beam or bar is used to connect the 2 surfaces being joined, (b) a more modern approach where the 1D element is replaced with an “equivalent” brick element, or (c) a third approach falls somewhere between where a “spider” and circular ring of elements is used to represent the spot weld. In all three cases there is an assumption that the cross section is circular. For some specialist cases such as plastic connectors (Heat Stakes) a new user defined weld is proposed. This paper will describe the approach which is based on the concept that a user generated tensor line (equivalent to the theoretical Force/Moment to stress algorithms built into the P2P approach) can be used along with special S-N curves create for different Heat Stake shapes.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Reducing Cycle Times of Refill Friction Stir Spot Welding in Automotive Aluminum Alloys

Brigham Young Univ-Yuri Hovanski
Brigham Young Univ.-Brigham Larsen
  • Technical Paper
  • 2020-01-0224
To be published on 2020-04-14 by SAE International in United States
Refill friction stir spot welding (RFSSW) is an emerging welding process that has shown great potential in joining automotive and aerospace aluminum alloys. Though the process has been in development for nearly a decade, RFSSW has yet to see wide-scale implementation in the automotive industry. A major barrier, preventing RFSSW from use by manufacturers, is the long cycle time that has been historically associated with making a weld. In order for RFSSW to become a readily implementable welding solution, cycle times must be reduced to an acceptable level, similar to that of well developed, competing spot joining processes. In the present work, an investigation of the RFSSW process is conducted to evaluate factors that have traditionally prevented the RFSSW process from achieving fast cycle times. Within this investigation, the relationship between cycle time and joint quality is explored, as is the meaning and measurement of cycle time in the RFSSW process. Claims and general sentiment found in prior literature are challenged regarding the potential for high-speed RFSSW joints to be made. The RFSSW weld design—as…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Methods to Control Adhesive Curing Induced Distortion in Hybrid Joining of Dissimilar Metals

Deere and Company, USA-Sankaran Subramaniam, Bradley Iverson, Doug Nimrick
John Deere India Pvt, Ltd.-Indrajit Malvade
  • Technical Paper
  • 2020-01-1053
To be published on 2020-04-14 by SAE International in United States
In lightweight structures with dissimilar metal designs, structural adhesive joining is a potential joining method. Adhesives help in reducing galvanic corrosion by minimizing physical contact between two dissimilar metals. Along with adhesives, fasteners are often used as a secondary joining method to hold the assembly together during adhesive curing. Therefore, a hybrid joint which is a combination of adhesives and mechanical fasteners is potential joining method to join dissimilar metals. However, when two dissimilar metals such as aluminum to steel are joined with hybrid joint by adhesive curing at elevated temperature, the distortion of assembly is observed when cooled at room temperature. This is due to the mismatch between coefficients of thermal expansion of aluminum vs steel. The adhesive may also experience residual stress and fracture. In this study, adhesive curing induced distortion is studied using 1.1 meter long specimens of aluminum to steel hybrid joint assembly. The base materials consist of 4.8 mm thick aluminum 6061 T6 joined to 1 mm thick UHSS with 30 mm adhesive overlap. One-part heat cured structural epoxy adhesive…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Parameter Sensitivity Study of Self-piercing Rivet Insertion Process using Finite Element and Machine Learning Method

Chongqing University-Yudong Fang, Zhenfei Zhan
Ford Motor Company-Li Huang, Shiyao Huang
  • Technical Paper
  • 2020-01-0219
To be published on 2020-04-14 by SAE International in United States
Self-piercing rivets (SPR) are efficient and economical joining methods for lightweight automotive body structure manufacturing. Finite element method (FEM) is a potential effective way to assess joining process while some uncertain parameters can be employed in the simulation based on the prior knowledge, which could lead to significant mismatches between CAE predictions and physical tests. Thus, a sensitivity study on critical CAE parameters is important to guide the high-fidelity modeling of SPR insertion Process. In this paper, a 2-D symmetrical CAE model is constructed to simulate the insertion process of the SPR using LS-DYNA/explicit. Then, several surrogate models are trained using machine learning methods to build the linkage between selected inputs (e.g. material properties, interfacial frictions, clamping force) and outputs (cross-section dimensions). It is found that it is feasible to train surrogate models with high accuracy to replace the time-consuming CAE simulations with a limited sampling volume. Based on trained surrogate models, an extensive sensitivity study is conducted to thoroughly understand the impact of a collection of CAE parameters. This research provides a solid foundation…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Methodology for Automotive Steel Wheels Life Assessment

Fraunhofer ITWM-Manfred Baecker, Axel Gallrein
MW Italia-Davide Rovarino, Luca Actis Comino
  • Technical Paper
  • 2020-01-1240
To be published on 2020-04-14 by SAE International in United States
A methodology for an efficient failure prediction of automotive steel wheels during fatigue experimental tests is proposed. The strategy joins the CDTire® simulative package effectiveness to a specific wheel finite element model in order to deeply monitor the stress distribution among the component to predict damage. The numerical model acts as a Software-in-the-loop and it is calibrated with experimental data. The developed tool, called VirtualWheel®, can be applied for the optimisation of design reducing prototyping and experimental test costs in the development phase. In the first section, the failure criterion is selected. In the second one, the conversion of hardware test-rig into virtual model is described in detail by focusing on critical aspects of finite element modelling. In conclusion, failure prediction is compared with experimental test results.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Crack Detection Method for Self-Piercing Riveting Button Images through Machine Learning

Chongqing University-Ling Jiang, Xuyang Wang, Zhenfei Zhan
Ford Motor Company-Li Huang, Shiyao Huang, Garret Huff, Amanda Freis
  • Technical Paper
  • 2020-01-0221
To be published on 2020-04-14 by SAE International in United States
Self-piercing riveting (SPR) is a key joining technique for lightweight materials, and it has been widely used in the automobile manufacturing. Manual visual crack inspection of SPR joints could be time-consuming and might rely on high-level training for engineers to distinguish features subjectively. This paper presents a machine learning based crack detection method for SPR button images. Firstly, sub-images were cropped from the button images and preprocessed into three categories (cracks, edges, others) as training samples. Then, Artificial Neural Network (ANN) was chosen as the classification algorithm for sub-images. During the training of ANN, three pattern descriptors were proposed as feature extractors of sub-images respectively, and compared with validation samples. Lastly, a search algorithm was developed to extend the application of the learned model from sub-images to the original button images. The preliminary results on non-cracked and cracked button images show that the proposed crack detection method could achieve an acceptable performance.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Fatigue Evaluation of Flow Drill Screw Joints Using the Equilibrium-Based Structural Stress Method

Engineering Mechanics Corp. of Columbus-Jeong Hong, Gery Wilkowski PhD
  • Technical Paper
  • 2020-01-0189
To be published on 2020-04-14 by SAE International in United States
According to increasing the demands of light-weight design in the automotive industry, the usage of thinner and lighter materials such as aluminum alloy has led to significant weight reduction. The joining of these materials has required new technologies in joining/fastening rather than welding. Flow drill screw (FDS) is one of the latest technologies to fasten sheet metal panels. This paper discusses the results of an evaluation of the fatigue characteristics of FDS joints based on experimental data and observations from the literature. It was observed that the important geometric parameters of FDS joints are the gap between panels and the extruded (or bulged) zone during screwing. Major failure modes were observed as panel failure which cracks grow from the inner surface of the panel around the bulged zone. In this paper, the fatigue evaluation procedure for FDS joints using the mesh-insensitive equilibrium-based structural stress (ESS) method was proposed. The ESS-based simplified modeling procedure was used for the fatigue evaluation procedure development for FDS joints. The effectiveness and applicability of the ESS-based simplified procedure for modeling…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Analysis of Sheet Metal Joining with Self-Piercing Riveting

Oakland Univ.-Sergey Golovashchenko
Oakland University-Srecko Zdravkovic
  • Technical Paper
  • 2020-01-0223
To be published on 2020-04-14 by SAE International in United States
Self-piercing riveting (SPR) has been in production in automotive industry since early 1990s. A substantial amount of experimental work was traditionally required in order to find an appropriate combination of rivet and anvil design to satisfy the required joint parameters. Presented study is describing the methodology of numerical simulation of SPR process and its experimental validation for Aluminum alloys and steels. Among material properties, the required information for numerical simulation includes stress-strain curves validated for the range of strains taking place in SPR process (up to 2.0 of true strain for sheets and up to 0.4 of true strain for the rivet) and parameters of fracture model for all involved materials: all sheets in the stack and the rivet material. Experimental data on stress-strain curves for extended range of strains was obtained based upon multistep rolling tensile testing procedure for the sheet metals. Parameters of the fracture model for sheets were defined by custom hole expansion test, and the parameter of the fracture model for the rivet was defined via expanding the tubular portion of…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Development of Exmani-Heat protector to Improve Sound Absorption using New Perforated Thin Aluminum Plate

Hyundai Motor Group-JAEGI SIM, Minsoo Kim, KwangMin Yoon
  • Technical Paper
  • 2020-01-0405
To be published on 2020-04-14 by SAE International in United States
This technology is a technology for reducing the gas flow noise generated from the noise of the vehicle, especially the exhaust system. The primary function of the heat protector is thermal shutdown. However, due to the increase in engine power, downsizing of engines, and the rise of consumer's eye level, solutions about noise are now emphasized. Established the manufacturing technology of 3-ply composite board which can absorb sound in the existing heat protector. For this purpose, mold technology for punching aluminum sheet, optimization technique for punching effect, unique high-strength / high-forming pattern design, sound absorbing material selection and composite sheet molding technology, and noise vibration reduction mounting technology for plate joining were developed.