Ohio State University
Colorado School of Mines
University of Tennessee, Knoxville
Last Reviewed: (not done)
The center is devoted to the development of advanced manufacturing technology associated with materials joining, including additive manufacturing. This involves the evaluation of weldability/joinability with respect to both existing and advanced material. Projects use a mix of computational and experimental tools to achieve the center objectives and meet the needs of its broad-based industrial membership.
Mission: The mission of the center is to advance the science and technology of advanced manufacturing as it applies to materials joining. The following are specific goals associated with this mission: 1) close the gap between material development and weldability, 2) develop scientifically-based methodologies for assessing material weldability/joinability that span nm to mm length scales, 3) develop experimental and computational tools for materials joining and advanced manufacturing, and 4) develop a new generation of materials joining engineers & scientists.
Rationale: US leadership in advanced manufacturing is critical to the economic health and well being of the country. Materials joining is an important aspect of advancing manufacturing, particulrly in the context of incorporating advanced materials into the manufacture of new products. Throughout the history of materials innovation, there are instances where the application of new, high performance materials has been limited, or precluded, by the inability to join them. A basic problem along the path from development to implementation is the lack of a structured, scientifically-based methodology for determining material “weldability”. The concept of weldability occurs at the intersection of the joining process and the materials’ response to the thermal and mechanical conditions that are imposed by the process. Considering the diverse need for materials in virtually every industry segment, it is critical to develop scientific methodologies to join these materials.
Needs: Technical needs related to materials joining in fossil and nuclear energy, transportation, defense, and petrochemical industries have been identified. These needs are grouped under five thrust areas within the center: 1) Material Performance, 2) Weldability Testing and Evaluation, 3) Process Innovation and Development, 4) Modeling, and 5) Additive Manufacturing. To address the above needs, this NSF Industry and University Cooperative research (I/UCRC) center was formed in 2010, originally known as the Center for Integrative Materials Joining Science for Energy Applications (CIMJSEA). The new name (Ma2JIC) reflects the broader mission of the center focussed on materials joining and advanced manufacturing for a wide range of industries.
Topics in this reserach area include the evaluation of the microstructure and properties of powder-based additive manufacturing processes, development of weldability testing approaches, modeling of the the process, and validation of additive manufacturing procedures using different types of powder-based equipment (powder feed versus powder bed).
Topics of research in this thrust include (a) dissimilar weld behavior in challenging petrochemical applications, including offshore platforms and deepwater exploration, (b) effect of PWHT on properties and corrosion resistance of clad steels, (c) stress corrosion cracking resistance of aluminum alloys for automotive applications, and (d)fundamental understanding of localized deformation under severe microstructural gradients.
Process Innovation and Development
Topics of research in this thrust include (a) wide gap brazing of Ni-ase alloys for aerospace applications, (b) laser welding for joining high-nitrogen stainless steels, and (c) development of overlay technology for applied corrrosion-resistant materials over steel.
Processand Materials Modeling
In this research thrust, the focus is on the development and deployment of computational models that can provide a comprehensive understanding of microstructure and performance in welds/joints, as a function of joining processes, and process parameters. Models are also being developed to predict material performance in harsh environments associated with advanced power generation schemes.
Weldability Testing and Evaluation
Topics of research in this thrust include (a) nickel-base alloys for supercritical boilers, (b) repair and maintenance of Cr-Mo grade steels, (c) development of standardized weldability test techniques for advanced materials, and (d) development of weldability tests for additive manufacturing applications.
The center supports activities at both the undergraduate and secondary school levels. Center members are encouraged to support Senior Design "capstone" projects that are linked to projects ongoing in the center. The OSU site has also started a high school intern program (2014) that engages students at local STEM schools in center research projects.
The Ohio State University, Colorado School of Mines, Lehigh University, and University of Wisconsin have many laboratories, which are relevant to the proposed center. Some of the salient data is provided. For more details, please contact the center director.
Gleeble 3800: This is a state-of-the-art thermo-mechanical simulator purchased in 2004 for performing testing and microstructure simulation. Samples can be prepared under protective atmosphere or vacuum. In addition to the standard “pocket jaw” module for standard testing, we also have a torsion unit that can be used to simulate processes that induce high strains and strain rates (such as friction stir processing). Standard testing includes hot ductility, strain-to-fracture, and a variety of specialized tests for evaluating weldability.
Button Melting Apparatus: A small button melting apparatus has been developed for alloy development, phase transformation analysis, and weldability testing. Using this equipment, small charges of material can be cast and their weldability and phase transformation behavior determined.
Characterization Laboratory: Equipment for metallographic preparation of samples (sectioning, mounting, polishing and etching) is available. This laboratory also has standard metallographic microscopes and microhardness (spot and mapping mode) testing equipment.
Clark-MXR CPA-2110 Femtosecond pulsed laser system: Ti-Sapphire C-P amplified PAV = 1.5 W, fp = 1-2 kHz, Tp = 150 fs
Spectra Physics FCstack™ Tornado TN50-106Q : Diode stack-pumped 50 watt, multi-mode Nd:YAG laser, A/O Q-switched, CW modes, Pav= 5- 35 W, fp = 1 - 50 kHz
Magnetic Pulse Processing Laboratory:This lab has two commercial and custom-built capacitor discharge equipments capable of crimp joining and magnetic pulse welding for tube to round or sheet-to-sheet. This lab also has full instrumentation including measurement of primary and secondary currents and 4 channels of photon Doppler velocimetry with 10 ns time resolution and <1% velocity accuracy over the time and velocity regimes seen in EMF. These experimental data can be used to test and calibrate numerical models. The laboratory has versions of these built on coupled differential equations as well as collaborating with LSTC on the on-going development of EM subroutines for LS-DYNA.
Plastic and Composites Joining Laboratory: The following equipments are available: Ultrasonic welders (20 and 40 kHz, 700 - 3500 watts), Variable frequency ultrasonic power supply, Vibration welding machine (200 to 280 Hz), Callanan 2 kW Radio Frequency Welder, Spin friction welding machines (inertia system up to 2" parts), Hot plate welder (8 x 8", 1000° F maximum), Induction welding machines (9 kHz-8 MHz and 2-15 kW), Hot gas welding equipment (150-1100° F w/ or w/o inert gas), Resistance implant welder, Laser welders (CO2 and Nd:YAG), High power laser diode through transmission welding and Plastics flame spraying equipment
Non-Destructive Evaluation Laboratory:The following equipments are available: Schlieren imaging system, Holographic inspection system, Acoustic holography system, Ultrasonic flaw detectors, Immersion test systems with X-Y positioners, Combined ultrasonic inspection mechanical loading system, Scanning acoustic microscope, Computer controlled radiographic system, Eddy current NDT and Magnetic particle inspection.
Computational Modeling: OSU has access to ThermoCalc®, DicTra®, JMatPro and associated iron, slag, aluminum, titanium, and nickel alloy databases. These tools have been used for both undergraduate research and teaching. OSU has proven track record of using finite element analyses codes to predict residual stress and distortion. For example, plastic strain based distortion prediction was developed at OSU by Prof. Tsai and his students. These tools will be leveraged for the center activities.
Center for Electron Microscopy and Analysis (CEMAS), based in the Materials Science and Engineering Department, operates world-class electron and ion microscopes and supporting equipment. It recently moved to a new site and has undergone a $10 million upgrade.
5 East Packer Avenue
Bethlehem, Pennsylvania, 18015
University of Tennessee, Knoxville
331 Ferris Hall
1508 Middle Drive
Knoxville, Tennessee, 37996