TMS 2020 - SAN DIEGO CALIFORNIA
The TMS (The Minerals, Metals and Materials Society) annual conference was held in San Diego, California this year. Some of the faculty members and students from the Materials and Manufacturing Sciences department were able to attend the conference and give presentations on their current research projects.
Dr. Brajendra Mishra attended the conference as the past president and TMS Foundation Trustee. In addition to this, Mishra organized the WPI Alumni & Guest Reception
Prof. Diana Lados was recognized at the TMS 2020 Conference with the Acta Materialia Silver Medal Award, which honors and recognizes significant scientific contributions and leadership from leaders in the midst of their careers. As the recipient of the award, Prof. Lados also presented the Acta Meterialia Silver Medal Lecture: "Integrative Materials Design and Additive Manufacturing in the Context of Industry 4.0"
Some of the faculty members and students who were able to attend the conference this year.
Presenter: Diana Lados
Title: Integrative Materials Design and Additive Manufacturing in the Context of Industry 4.0 (Acta Materialia Silver Medal Lecture)
Abstract: Manufacturing of materials is marching into an era where the gap between conceptualization and commercialization can be significantly reduced by utilizing an integrated materials design approach, materials informatics, and machine learning. Additive manufacturing (AM), which enables fabrication of parts with complex geometries directly from 3D models, is a major driving force in this new design and manufacturing era. In order to fully develop Industry 4.0 capabilities, the field of AM is seeing significant research efforts focused on developing comprehensive and well-integrated processing-microstructure-properties knowledge and databases, as well as multi-scale modeling tools to be used in a data-driven materials design and manufacturing approach. There are many metal AM processes that have been developed and are being evaluated for adoption in high-integrity applications. In this context, opportunities for qualification of structural AM materials will be discussed, with emphasis on effective methodologies for rapid material characterization and process optimization for fatigue performance.
Presenter: Ankaksha Gupta
Title: Review of coating removal techniques from metal substrates
Advisor: Dr. Brajendra Mishra
Abstract: In recent years, protection against corrosion, high temperature, and other extreme environmental service conditions are provided by applying different coatings to metal substrates. These materials mainly find applications in aerospace, automobile and commercial industries. Coatings mainly differ depending on the type of application, substrate, deposition technique, and properties desired. It is necessary to remove these coatings during inspection, refurbishment of damaged coating, and remanufacturing of end-of-life materials. Some removal techniques commonly applied are chemical stripping, high-pressure water jet technique, and impacting abrasive media. While selecting a suitable removal technique, it is essential to consider environmental, economic, and safety hazards. This review gives an in-depth review into the existing coating removal techniques and the various factors that must be considered while choosing a removal technique, and provides case studies of currently in-use coated materials.
Presenter: Anthony Spangenberger
Title: Fatigue Crack Growth in Structural Cast Aluminum Alloys: Microstructural Mechanisms, Modeling Strategies, and Integrated Design
Advisor: Prof. Diana Lados
Authors: Anthony Spangenberger, Diana Lados
Abstract: Advanced design for fatigue crack growth (FCG) resistance requires development and integration of phenomenological models across a range of size scales and mechanistic regimes. To address this need, numerical and computational models of small and long FCG have been developed for materials having a ductile matrix and brittle reinforcing phases, and are supported by experimental testing of cast A356 aluminum alloy. A combined physical/statistical predictive model of microstructurally small crack growth has been developed on the basis of transforming long FCG data using easily measured microstructural parameters for secondary phase-controlled behavior. Complementary to this, an extended finite element model of microstructurally-based small and long FCG was developed as part of a through-process approach to component development and material selection for enhanced structural integrity. Both models are validated by conventional FCG testing, and supported by novel characterization methods for properties at the microstructure scale.
Presenter: Diana Lados
Title: Fatigue Crack Growth Mechanisms and Design-Qualification Considerations in Ti-6Al-4V Alloys Fabricated by Three Powder-Based Additive Manufacturing Technologies (Invited talk)
Authors: Yuwei Zhai, Haize Galarraga, Robert Warren, Diana Lados
Abstract: There are many additive manufacturing (AM) processes that have been used for the fabrication and repair of Ti-6Al-4V components, each process providing different mechanical properties due to its unique thermal history. This presentation systematically discusses and compares the processing-microstructure-property relationships in Ti-6Al-4V alloys produced by three powder-based AM technologies: Laser Engineered Net Shaping (LENS), Electron Beam Powder Bed Fusion (EBM), and Laser Powder Bed Fusion (LPB). First, the relationships between thermal histories and resulting microstructures will be presented and discussed. Further, the fatigue crack growth behavior for different orientations (with respect to the deposition direction), stress ratios, and heat-treating conditions will be addressed, and damage mechanisms at the microstructural scale at different crack growth stages will be identified. The results will then be broadly reviewed from the perspective of design for fatigue resistance and life predictions in high-integrity applications. Opportunities and directions towards material/part qualification will also be discussed.
Presenter: Jack Grubbs
Title: Comparing Traditional and Designer Alloy Feedstock Powders for Additive Manufacturing
Advisor: Prof. Danielle Cote
Authors: Jack Grubbs, Kyle Tsaknopoulos, Danielle Cote
Abstract: Metal powder-based additive manufacturing (AM) techniques often rely on traditional alloys to create a processed part. However, processing and performance capabilities are not optimized with these traditional powders, prompting a need for designer feedstock material. Considering variations in powder morphology and composition, research was conducted to compare both traditional and designer feedstock powders for AM applications. Ideal feedstock powder for AM can be characterized by narrow particle size-shape distributions, as well as superior powder properties. Powder properties are directly connected to internal microstructure; thus, a precisely controlled microstructure is necessary for optimal powder performance. A powder's microstructure can be manipulated by thermal treatments, therefore both heat-treated and as-received powders were evaluated. Powder morphology was characterized using a synchronous laser diffraction and dynamic image particle analyzer, and the microstructure was analyzed using scanning electron microscopy, energy dispersive x-ray spectroscopy, and nanoindentation. Analysis was guided through computational thermodynamic and kinetic models.
Presenter: Kübra Karayağız
Title: Phase-Field Modeling of Galvanic Corrosion in Magnesium-Aluminum Joints
Advisors: Dr. Adam Powell, Dr. Brajendra Mishra
Authors: Kübra Karayağız, Adam Powell, Qingli Ding, Brajendra Mishra
Abstract: Several future light-weight automotive designs require joining aluminum and magnesium alloy parts in order to take maximum advantage of the best properties of both materials. However, such joints inherently give rise to galvanic corrosion between the two metals, their intermetallic compounds, and other phases in the alloys themselves. Presented here is a formulation with two-dimensional results for multiscale modeling of this corrosion, consisting of macroscopic computation of galvanic potential distribution over the joint, coupled with grain-level phase-field modeling of micro-galvanic material degradation at each phase. Modeling is guided by experimental observations of aqueous corrosion of diffusion-bonded magnesium-aluminum couples in order to provide a relatively simple geometry and microstructure for initial development. The formulation is intended for later use with more complex geometries and joints including friction stir welds between magnesium and aluminum alloy sheet.
Presenter: Matthew Gleason
Title: Evaluation of Two Novel Techniques to Characterize the Bond Strengths of Cold Sprayed Single Particle Impacts
Advisor: Prof. Danielle Cote
Authors: Matthew Gleason, Kyle Tsaknopoulos, Danielle Cote
Abstract: In order to better understand the cold spray bonding process, it is necessary to experimentally assess the bond strengths of individual particle impacts. While there exist several techniques for this purpose in the literature, each possess limitations that restrict their usefulness. Some are too time-intensive to gather enough data for statistical investigations, while others sacrifice measurement accuracy. We have previously proposed two novel techniques that exceed these limitations, each allowing for high throughput characterization while still maintaining high accuracy. One is a novel method of sample preparation that results in a sample geometry that is easy to test, while the other is a type of crack propagation test. In this work, preliminary experiments are performed with both methods to evaluate and compare their effectiveness.
Presenter: Matthew Ryder
Title: Optimization of Additively Manufactured Low Carbon Steels for Fatigue-Critical Applications
Advisor: Prof. Diana Lados
Authors: Matthew Ryder, Colt Montgomery, Michael Brand, Robin Pacheco, John Carpenter, Peggy Jones, Diana Lados
Abstract: Additive manufacturing (AM) provides unparalleled flexibility in component design, and a comprehensive understanding of the AM parts’ behavior is imperative for their implementation in fatigue-critical applications. Two low carbon steels fabricated by Laser Powder Bed (LPB) have been investigated in this study – in both as-fabricated and heat-treated conditions – and compared to their wrought counterparts. Build parameters have been selected through melt pool geometry optimization, and used in the fabrication of tensile, fatigue, and fatigue crack growth specimens. Microstructure, yield and tensile strengths, and hardness have been evaluated for all materials and conditions. Residual stresses have been predicted using DANTE® simulations, and experimentally measured via x-ray diffraction, the contour method, and notch clamping on fatigue crack growth (compact tension) specimens. Through systematic high-cycle fatigue (R=-1) and fatigue crack growth (R=0.1, 0.8) testing and characterization, crack initiation and propagation mechanisms have been identified and used in the process-microstructure-performance optimization.
Presenter: Timothy Piette
Title: Microstructure, Mechanical Properties, and Fatigue Damage Mechanisms in Laser Powder Bed Al-10Si-0.4Mg Alloys
Advisor: Prof. Diana Lados
Authors: Timothy Piette, Robert Warren, Edward Hummelt, Diana Lados
Abstract: Laser powder bed (LPB) manufactured Al-10Si-0.4Mg was studied in as-fabricated, T6, and HIP+T6 conditions, to understand the effects of microstructure and heat treatment on mechanical properties. Tensile and fatigue crack growth (FCG) properties and behavior were compared with those of conventionally-cast counterparts and related to build orientation and post-processing conditions. The as-fabricated LPB alloys show lower FCG response compared to the conventionally-cast and heat-treated LPB alloys. Anisotropic residual stresses in the as-fabricated condition affect the FCG thresholds, resulting in differences between build orientations. Heat treatments alter the microstructure, which causes loss of orientation dependence on properties, improves FCG threshold values, and changes the crack growth mechanisms. Fatigue testing in high-cycle fatigue regime was performed to relate the effects of build orientation, heat treatment, surface condition, and defect morphology and distribution (evaluated using x-ray computed tomography) to fatigue life. Recommendations for microstructure and post-processing optimization for fatigue-critical applications are provided.