Defects and Properties of Cast Metals IV: On-Demand Oral Presentations
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Solidification Committee
Program Organizers: Lang Yuan, University of South Carolina; Brian Thomas, Colorado School of Mines; Peter Lee, University College London; Mark Jolly, Cranfield University; Alex Plotkowski, Oak Ridge National Laboratory; Andrew Kao, University of Greenwich; Kyle Fezi, Fort Wayne Metals
Monday 8:00 AM
March 14, 2022
Room: Materials Processing
Location: On-Demand Room
Research Progress of Composite Preparation Technology of Bimetallic Wire: Chenglin Li1; Ting-an Zhang1; Yan Liu1; 1Northeastern University
The bimetallic composite wire is concentrically covered with another metal layer on the outer surface of the metal core wire, so that the two metals form an interatomic bond at the interface to become a whole metal wire. Under the premise of ensuring the performance, it has the advantages of two kinds of metals at the same time. The bimetal composite wire can save copper resources, reduce production costs, and improve product performance. With the development of China's wire and cable industry and railway industry, bimetallic composite wires are bound to become popular products and have huge market prospects.This article introduces the preparation technology of bimetallic composite wire from solid-state method to liquid method, analyzes its preparation mechanism, and looks forward to the future trend, hoping to provide a reference for the rapid preparation of high-quality bimetallic wire.
Porosity Defects in High Pressure Die Castings: Mechanisms and Uncertainties: Shishira Bhagavath1; Zhixuan Gong2; Tim Wigger2; Saurabh Shah2; Shashidhara Marathe3; Bita Ghaffari4; Mei Li4; Shyamprasad Karagadde1; Peter Lee2; 1Indian institute of Technology Bombay, India; 2University College London, UK; 3Diamond Light Source, UK; 4Ford Research and Advanced Engineering, Dearborn, USA
Aluminium alloy components produced from high-pressure die casting (HPDC) are used in key automotive components, with strict requirements on their tensile, compressive and fatigue strengths. However, the mechanical properties may be limited by microstructural features such as porosity that form during the late stages of solidification and semi-solid deformation in the HPDC process. In this study, a thermomechanical process simulator and real time synchrotron X-ray imaging was used to capture the microstructural development of semi-solid alloys during injection into a miniature die cavity. Using image analysis and digital volume correlation the complex interaction of semi-solid flow, shear localisation, and defect formation was elucidated. The results were then correlated to industrial HPDC components formed at various pressure conditions using lab-scale X-ray tomography. By quantifying the shape, size and location of the defects and correlating this with the in-situ studies, the nature of the defect forming mechanisms is ascertained.
Probabilistic Multiscale Finite Element Model for Predicting Strength and Fracture Strain of Cast Al-Si-Mg Alloy: Woojin Jeong1; Chanyang Kim1; Chung-An Lee2; Hyukjong Bong3; Seung-Hyun Hong2; Myoung-Gyu Lee1; 1Seoul National University; 2Hyundai Motor Company; 3Korea Institute of Materials Science
The strength and ductility of cast Al-Si-Mg alloy are predicted from a multi-scale finite element model that integrates the Mori-Tanaka (MT) mean field homogenization and the Gurson-Tvergaard-Needleman (GTN) ductile fracture model. The MT mean field method calculates the stress of Si particle embedded in the aluminum matrix and the nucleation of void is determined if the stress satisfies a critical failure value. The nucleated voids from the cracked Si particles grow and finally initiate the ductile fracture of matrix under the scheme of GTN approach. Moreover, the cracking of Si particles is identified by applying the Weibull distribution function, which reproduces the probabilistic characteristics of failure under various stress states. The developed finite element model is validated by predicting the tensile failure strengths and strains of different geometries of specimens covering shear to biaxial modes. The comparison shows reasonably good agreement with experimental failure data.
Hybrid Additive Manufacturing of Island Grain Bicrystals: Logan Ware1; Benjamin Herstein2; Yuxuan Zhang3; Hassina Bilheux3; Zachary Cordero4; 1Purdue University; 2Rice University; 3Oak Ridge National Laboratory; 4Massachusetts Institute of Technology
We report a hybrid additive manufacturing-based directional solidification technique which can fabricate tailored, three-dimensional crystal structures. This technique can manufacture single crystal, bicrystal, tricrystal, and higher-order oligocrystalline parts whose grain boundary networks are continuously varied and controlled by the part geometry. By designing the part geometry and controlling the contrast in thermal conductivity of the mold material and the metal/alloy, planar solidification fronts can be manipulated to form custom grain shapes and orientations. Polycrystalline parts with tailored grain boundary properties can be manufactured quickly by leveraging additive manufacturing for fast iteration and fabrication. We demonstrate this technique by growing a novel island grain bicrystal and measuring the energy of the grain boundary as a function of the grain boundary plane in a continuous manner. Applications of this technique to defect study are also briefly reviewed.
Reduced-Order Multiscale Modeling of Elasto-Plastic Cast Alloys with Process-Induced Porosity: Shiguang Deng1; Carl Soderhjelm1; Diran Apelian1; Ramin Bostanabad1; 1University of California Irvine
Cast aluminum alloys often contain heterogeneously distributed pores of complex morphologies that significantly affect material behaviors. In this talk, we will introduce a computationally efficient reduced-order multiscale framework to simulate the behavior of metallic components with process-induced porosity under irreversible nonlinear deformations. Major components of our approach include: (1) a data compression stage which dramatically reduces the number of degrees of freedom by agglomerating neighboring finite element nodes; (2) a novel reduced-order method which projects displacement vectors into a lower dimensional space where the material’s elasto-plastic behaviors are approximated; and (3) a porosity oriented microstructure reconstruction algorithm which mimics the material’s local heterogeneity with reconstructed pores from tomography characterization. We will illustrate the effects of spatially varying microstructures on cast alloy behaviors and compare our approach against the results from direct numerical simulations to demonstrate its performance and versatility.
Modification of Cast and Wrought Aluminum Parts Using Hybrid Laser Hot-wire Manufacturing: Gerry Knapp1; Thomas Feldhausen1; Ying Yang1; Benjamin Stump1; Donovan Leonard1; Alex Plotkowski1; 1Oak Ridge National Laboratory
Die-casting and hydroforming of aluminum parts are critical manufacturing processes for automotive applications. However, aluminum alloys with desirable specific strength or wear resistance are not always formable in the desired geometries. We used laser hot-wire hybrid manufacturing to create locally modified cast and wrought aluminum alloy substrates by depositing and machining dissimilar aluminum alloy features. Preliminary work focused on determining printable wire alloys and characterization of the interface of the deposited material with the substrates. High throughput thermodynamic calculations using a multi-component Al alloy database helped screen combinations of wire and substrate alloys based on material hot cracking sensitivity at the interface. Al 4043 wire was chosen for high printability with cast A356 alloy ingot and 6111 plates as substrates. Mechanical testing and characterization of the interface region were performed. This work was supported by the U.S. Department of Energy – Vehicle Technology Office Light Metals Core Program.