MIT 2020 Alloy Design Workshop

Prof Christopher Hutchinson, from Monash University, delivered a talk at the 2020 Alloy Design Workshop hosted by the Massachusetts Institute of Technology (MIT) on 4th December 2020. The workshop had an impressive line-up, including: Prof Hugo Sandim (University of Sao Paulo), Prof Zhaoping Lu (University of Science and Technology Beijing), Prof Gregory Olson (MIT), Prof John Ågren (KTH), Prof Francisca Caballero (Spanish National Research Council), Prof Davesh Misra (University of Texas at El Paso), Prof John Speer (Colorado School of Mines), Prof Cem Tasan (MIT) and Prof Christopher Hutchinson (Monash University).

Prof Hutchinson’s talk, entitled Damage resistant microstructures generated from chemically patterned austenite was very well received by the international audience and led to some rich discussions in the Q&A session that followed. The workshop covered the most recent ideas to push the limits of metastability-engineering towards steels with superior damage resistance, and it was a great opportunity to showcase the excellent work conducted by Monash and mineAlloy researchers.

mineAlloy annual meeting 2020

The mineAlloy training centre held its annual meeting on 24th November 2020 in a rather unusual setting. Given the travel restrictions and the social distancing rules in effect at the time of the meeting, the attendees connected remotely, from their home office or from geographically dispersed meeting rooms, through a videoconferencing platform.

The event offered a cross section of the research activities of mineAlloy students and postdoctoral fellows and it also gave the attendees an opportunity to learn more about the resources and expertise available across the Centre. The meeting finished with a valuable discussion with the industry partners on the challenges and opportunities that became apparent during the year.

Thanks to the organising committee for the effort: Abhishek Jain, Chunkit Sit, Roshan Sasi, Alireza Vahid, Jiangting Wang and Arul Varman.

2nd mineAlloy workshop on computational thermodynamics and kinetics

mineAlloy hosted the 2nd Workshop on Computational Thermodynamics and Kinetics on Tuesday 24th November 2020. The event was attended by more than 50 students and researchers from academia and industry. Dr Richard Ball represented ThermoCalc, who supported this event, and he provided a summary of the recent improvements in the software and the thermodynamic databases. Following this presentation, Dr Tiger Tang from Weir Minerals offered a few examples to illustrate how ThermoCalc is used in a commercial/industrial context. Finally, the workshop on computational thermodynamics and kinetics was delivered by Prof Christopher Hutchinson and Dr Yuxiang Wu from Monash University. The presenters covered a wide range of topics, including: thermodynamic equilibrium calculations and Scheil-Gulliver simulations using ThermoCalc, solidification, homogenisation and microsegregation simulations using DICTRA, as well as complex alloy composition and heat treatment optimisation using the ThermoCalc toolbox for MATLAB.

Pioneering friction stir additive manufacturing of steels

Dr Ehsan Farabi has recently joined the mineAlloy team at Deakin University. Ehsan is a physical metallurgist with interest in developing processing-structure-property links for advanced structural materials, mainly steels and titanium alloys. He has expertise in state-of-the-art characterisation techniques, such as electron microscopy (SEM), electron backscattered and transmission diffraction (EBSD and TKD), focused-ion beam (FIB), transmission electron microscopy (TEM). Ehsan specialises in the analysis of complex microstructures, combining experimental results with physical and metallurgical principles. His research is focused on the development of new alloys for advanced manufacturing. This includes understanding and predicting material behaviour, phase transformations, and microstructure evolution during material processing. Ehsan’s current project involves a fundamental study of the process-structure-property relationship of advanced steels during friction stir additive manufacturing (FSAM).

Chun Kit completes project on direct laser deposition of WC/Co

Chun Kit Sit has submitted his Master’s thesis on Direct Laser Deposition (DLD) of WC/Co cermets as wear-resistant coatings. WC/Co cermets are composite materials composed of tungsten carbide (ceramic) in a cobalt binder (metallic). WC/Co cermets are especially hard and wear resistant but their traditional manufacturing processes are expensive.

Direct laser deposition (DLC) of WC/Co is an alternative route for the fabrication of wear-resistant surfaces and it also opens the possibility of repairing used components. This is a particularly interesting option since the wear resistant material can be placed where it is most required, while the bulk of the component can be made from cheaper or tougher materials.

This thesis reports the process optimisation of DLD of WC/17Co coatings on a low carbon mild steel substrate and examines the wear performance of the coatings in both low-stress (ASTM B65) and high-stress (ASTM B611) wear tests.

Refinement of primary carbides in hypereutectic high-chromium cast irons

mineAlloy researchers from University of Queensland and Weir Minerals have recently published a review paper on the refinement of primary carbides in hypereutectic high-chromium cast irons. High-chromium cast irons (HCCIs) are widely used in mining, minerals and cementation industries. The large volume fraction of coarse primary carbides (M7C3) imparts excellent wear resistance, but it also results in high cracking susceptibility and early failure of components, particularly under impact loading. The mechanical performance of HCCIs is correlated with the microstructure of the matrix, as well as the size, shape, volume fraction and distribution of primary carbides. This paper comprehensively reviews the currently available methods to modify the primary M7C3 carbides in various HCCIs and, ultimately, to optimise their mechanical properties for wear resistant applications.

Follow this link to the full paper: https://doi.org/10.1007/s10853-020-05260-8

Postdoc in Advanced Characterisation

Dr Jiangting Wang is a research fellow and FIB-SEM manager at the Institute for Frontier Materials, Deakin University. He is specialised in advanced material characterisation, such as scanning electron microscopy (SEM), electron backscattered diffraction (EBSD), focused-ion beam (FIB), transmission electron microscopy (TEM), and atom probe tomography (APT). His previous research focused on understanding the microstructure and mechanical behaviours of high-strength low-alloy (HSLA) steels, twinning-induced plasticity (TWIP) steels, and magnesium alloys, using advanced characterisation techniques.

He joined the mineAlloy team in February 2020, to investigate the nano-scale microstructures and fundamental strengthening mechanisms of mining alloys using EBSD, FIB, TEM, and APT techniques. His focus will be on the precipitation-hardened Hadfield steels, high chromium cast iron, and high-strength bainitic steels. He will also be involved in characterising additively manufactured mining alloys.

More details about his research areas and publications can be found in the following link.

http://www.deakin.edu.au/about-deakin/people/jiangting-wang

Running DEM simulations at the National Computational Infrastructure

The researchers of mineAlloy, Vadim Zolotarevskiy and Michael Pereira, have been recently granted with access to the National Computational Infrastructure (NCI). The NCI facility operates Gadi – the most powerful Australian supercomputer. Gadi, that was launched in the beginning of 2020 and already ranked as 24th in the TOP500 list of the global supercomputers, makes it possible to conduct fast computations that rely on high-end CPU as well as GPU performance with the latest available hardware. Such an opportunity addresses the challenges of mineAlloy especially in the field of Discrete Element Method modelling, where time-efficient yet accurate simulations of complex multi-particle systems are of the top priorities.

Design, modelling and characterisation of wear-resistant steels

Yuxiang Wu is currently a research fellow in the Department of Materials Science and Engineering at Monash University. His work involves quantitative studies of microstructure development with both experimental and modelling components. He received his PhD in Materials Science and Engineering from Monash University in 2019. In the mineAlloy training centre, Yuxiang will provide support on the design, modelling and characterisation of wear-resistant steels.

Confirmations and completion

Congratulations to George Galis for successfully completing his confirmation of candidature at University of Queensland earlier this month. In this way, George joins the cohort of mineAlloy students who completed their confirmation of candidature this year, including: Abhishek Jain at University of Queensland, and Vamshi Chennuri, Roshan Sasi and Eigor Petry at Deakin University. In addition, Guillaume Bruel was recently awarded a Masters degree from Deakin University for his work on ‘Precipitation hardening of Fe-Mn-C steels for wear resistance improvement’. We celebrate the hard work and success of our HDR students in such challenging times. Well done, guys!

Xin starts master’s at Deakin

Xin Zheng has started his Master of Engineering project with the mineAlloy team at Deakin University. The project will use DEM modelling to develop design principles for titanium carbide inserts embedded in the mantles of cone crushers.

Xin recently completed his Bachelor of Mechanical Engineering (Honours) degree. His thesis was titled “Computational fluid dynamic simulation of drainage cannula in veno-arterial ECMO applications”.

Xin also completed a three-month internship with the mineAlloy team in 2019. During his internship, Xin became familiar with the Rocky DEM software, while conducting fundamental studies of particle-surface impacts and the effect of modelling parameters on the outputs.

Rocky DEM workshop

LEAP Australia and ESSS delivered a workshop on Rocky DEM software to graduate students and postdoctoral researchers from the Institute for Frontier Materials and the School of Engineering at Deakin University.

The presenters, Marcus Reis and Leon White, had originally planned to visit Waurn Ponds, but they had to deliver the workshop over ZOOM instead, because of the recent COVID19 travel restrictions.

The workshop covered the capabilities of this DEM software package in a broad context, and the researchers discussed its particular use in wear applications. The presenters also introduced some of the new features included in forthcoming versions of Rocky, expected to be released later in 2020.