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Speakers’ List 
Version: May 1, 2014 
Page 1 of 104 
Stream: Advanced Materials Manufacturing  
Paper No.: 8583  
Paper Title: Fatigue behavior of a nickel-based filler material for SMAW welding of steels  
Jeremy Leroy, Ecole Polytechnique de Montréal; Romain Taliere, Ecole Polytechnique de Montréal; René Begin, Sodel Canada; 
Khemici Badri, Sodel Canada;  
The main objective is to characterise and understand the fatigue behaviour of two nickel base filler materials (FM) used to 
repair high strength steel structures by Shielded Metal Arc Welding. Fatigue test samples were manufactured from a 102mm 
thick and 1524mm long multipass welds performed on Weldox700 martensitic stainless steel. Axial fatigue tests parallel and 
perpendicular to the welding direction were performed at a frequency of 10Hz. In the first case (tests parallel) sample were 
fully contained in the FM and in the second case (tests perpendicular) the specimen gage length covered the base material, the 
heat affected zone (HAZ) and the fusion line (FL). To complement the fatigue tests, microstructural analysis, microhardness 
profiles and tensile tests were also performed. Axial fatigue tests revealed that all-welded (FM) specimens have higher axial 
fatigue strength, 160MPa for 2.106cycles, than those containing the base material and the HAZ, 134MPa for 2.106cycles. For 
the specimens? majority, fatigue crack initiated from a welding defect. In the case of perpendicular tests, these defects were 
located at approximately 2mm from the FL. Three hypotheses may explain failure location: dilution, gradient of defect density 
or defect size and/or gradient of mechanical properties (microhardness).  
Paper No.: 8348  
Paper Title: Effect of Ga on the Wettability of Cu-rich Braze Fillers on Steel  
Simon Pauly, IFW Dresden; Ivan Kaban, IFW Dresden; Gunther Wiehl, Umicore AG & Co. KG; Uta Kühn, IFW Dresden; Jürgen 
Eckert, IFW Dresden; Frank Silze 
In the present work, the effect of Ga on the wetting behavior of Cu-rich braze fillers on steel has been investigated. The contact 
angles of a series of Cu-GaX (X=10-30 wt-%) alloys on steel 304L as well as the surface tension of these alloys were measured 
by the sessile drop method. All Cu-Ga compositions show pronounced wetting. To better understand this behaviour the 
viscosity of the braze fillers and the reactions at the interface with the substrate were determined. Ga readily diffuses into the 
steel and leads to the formation of multiple intermetallic phases depending on the Ga content and the brazing temperature. 
Thus, Ga improves the bonding between the brazing alloy and the steel substrate. Finally, transmission electron microscopy 
reveals that Ga might remove the oxide layer on the steel generally impeding proper wetting and as a result enhances the 
Paper No.: 8426  
Paper Title: INVITED: Effect of welding process on the tensile strength of friction stir welded Ti/Al dissimilar joints  
Jilin Xie, ; Liming Ke, ; Jidong Kang, Yuhua Chen;  
Complementary characteristics of Ti and Al are often required in aircraft or high speed train applications, such as increased 
strength, lowered weight and cost. However, it is difficult to obtain sound dissimilar welds of these two types of alloys using 
traditional fusion welding processes because of the great differences in their performance. There are several reports on 
friction stir welding (FSW) of Ti/Al dissimilar alloys although the ultimate tensile strength of the resulting joint is only 73% of 
base material strength which is unsatisfactory. To improve the tensile strength of friction stir welded joint of Ti/Al, influence 
of tool rotation speed, welding speed and the pin offset to the Al side (the distance between the centre line of the tool pin to 

Speakers’ List 
Version: May 1, 2014 
Page 2 of 104 
the contact surface) on tensile strength were systematically investigated in this paper. 3mm thick of TC4 titanium alloy and 
2A14 aluminum alloy was butt joined using friction stir welding. The results show that the pin offset to the Al side has 
significant influence on the tensile strength of the joints. When the pin offset was 0 mm and 1 mm, the joints were easy to 
crack. Tensile strength increases with increasing pin offset. When the pin offset was fixed at 2.5mm, the tensile strength of the 
joints increased first and then decreased with increasing welding speed and tool rotation speed. The joint reaches the highest 
strength of 348MPa that is 82.5% of the tensile strength of the aluminum alloy base metal at a combination of tool rotation 
speed of 700r/min and the welding speed of 60mm/min . The results also show that the fracture location and the tensile 
strength of the joint depends on microstructure and intermetallic phases formed in the weld seam. For the joint with the 
lowest strength, fracture occurs in the interface of Ti and Al base metal where a large amount of brittle phase of TiAl3 exist. 
For the joint with the highest strength, it fractures in the heat affected zone of Al base metal as TiAl phase formed in the weld 
seam in addition to TiAl3 phase that offers better plasticity.  
Paper No.: 8463  
Paper Title: INVITED: Laser-MIG Hybrid Welding of Maraging Steel  
G. Padmanabham, International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI); L. Subashini, 
International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI); K.V. Phani Prabhakar, 
International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI);  
Laser-arc Hybrid Welding (LHW) is a relatively recent concept which effectively combines the advantages of laser welding 
such as the high depth of penetration, low heat input, high welding speed and the positive aspects of arc welding such as better 
edge bridging and possibility to add filler. For example, steel sections upto 12 mm thickness have been successfully welded in 
a single pass at a welding speed of 1 m/minute using a 3.5 kW CO2 laser in combination with a MIG arc. Maraging steel of 
grade M250 is widely used in the aerospace industry in thicknesses upto 10 mm. Conventionally, it is possible to MIG weld 
such thicknesses in 3-5 passes employing V-Groove joint preparation. However, this multi-pass welding results in formation of 
reverted austenite in the weld zone after post weld aging; and the high heat input widens the reverted austenite containing 
heat affected zone which is popularly known as the dark zone/eyebrow zone. Both these zones are detrimental to strength of 
the welded joint, specifically the fracture toughness. The width of the dark band is an important factor because, thinner the 
band, it is supported more effectively by the surrounding material. Therefore, in order to avoid multi-pass welding and reduce 
the overall heat input, single-pass laser-MIG hybrid welding was attempted on 10 mm thick maraging steel M 250 plates using 
a hybrid laser arc welding system comprising a 3.5 kW CO2 slab laser and a MIG welding system. Simultaneously, multi-pass 
MIG welds also are produced. Both the laser-MIG hybrid and MIG welds are characterized microstructurally and subjected to 
mechanical tests such as tensile and fracture toughness in as-welded and post weld aged condition. The amount and 
distribution of reverted austenite in the fusion zone and width of the dark band was found to be different. Hybrid welds 
showed only a 120µm dark band zone and improved mechanical properties. Laser-hybrid and MIG welding investigations 
carried out on thick section maraging steel M 250 will be presented in detail, including microstructure, tensile properties and 
fracture toughness of the welds. To the best of the knowledge of the authors there are no reports on laser-MIG hybrid welding 
of maraging steels.  
Paper No.: 8504  
Paper Title: INVITED: In-situ Synchrotron S-ray Study of Ultrasound Cavitation and Its Effect on Solidification 
Jiawei Mi, University of Hull; D.Y. Tan, University of Hull; T.L. Lee, University of Hull; J.C. Khong, University of Hull; T. 
Connolley, Diamond Light Source; K. Fezzaa, Advanced Photon Source;  
One of the remaining scientific and technological challenges in solidification processes and many other materials synthesis 
processes involving phase change is to understand precisely and predict quantitatively the dynamics of grain nucleation and 
the subsequent nano/microstructure evolution in a highly dynamic and non-equilibrium conditions, such as the solidification 
nano/microstructure under the influence of an ultrasound field. Although considerable progress has been made in studying 

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Version: May 1, 2014 
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the mechanism and effectiveness of using ultrasound waves to manipulate alloy solidification microstructure, Uncertainties 
remain in both the underlying physics of how microstructure evolve under ultrasonic waves, and the best technological 
approach to control the final microstructure and properties. We used the ultrafast synchrotron X-ray phase contrast imaging 
facility housed at the Advanced Photon Source, Argonne National Laboratory, USA; and the high speed synchrotron X-ray 
imaging facility at the Diamond Light Source to study in-situ the highly transient and dynamic interactions between the 
liquid/semisolid metal and ultrasonic waves/bubbles. The dynamics of ultrasonic bubbles in liquid metal and their 
interactions with the solidifying phases were captured in-situ for the first time. The experiments were complemented by the 
simulations of the acoustic pressure field, the pulsing of the bubbles and the associated forces acting onto the solidifying 
phases, providing more quantitative understanding for using ultrasound to control the growth of dendritic grains and to 
enhance grain multiplication effects for grain refinement.  
Paper No.: 8300  
Paper Title: INVITED: Tensile Properties and Microstructure of Squeeze Cast Magnesium Matrix Composite Reinforced 
with 35 vol.% of Al2O3 Fibers  
XUEZHI ZHANG, University of Windsor; HENRY HU, University of Windsor;  
Magnesium alloy AM60 matrix-based composite reinforced with 35 vol % of Al2O3 fibers were fabricated by preform 
infiltration and squeeze casting technique. The optical and SEM microstructural analysis indicate that the alumina fiber 
distribute uniformly in the preform. The mechanical properties were investigated in comparison with the matrix alloy AM60. 
The results of tensile testing indicated that the addition of Al2O3fibres to magnesium alloy AM60 led to a significant 
improvement in mechanical properties. In particular, the ultimate and yield strengths and modulus of the composites were 
enhanced considerably. However, the notably increase in strengths was at sacrifice in elongation.  
Paper No.: 8320  
Paper Title: Effect of Testing Temperature on Shear Tensile Properties of a Friction Stir Lap Welded AZ31B-H24 
Magnesium Alloy  
Daolun Chen, Ryerson University, Toronto; Xinjin Cao, National Research Council Canada (NRC Aerospce), Montreal; Priti 
Wanjara, National Research Council Canada (NRC Aerospce), Montreal; Srinivasa Bhukya 
In this study, 2-mm thick AZ31B-H24 Mg alloy sheets were friction stir welded in a lap joint configuration at different tool 
rotational rates (1000 and 1500 rpm) and welding speeds (10 and 20 mm/s). The tensile behavior of these lap joints was then 
evaluated at low (-40°C), room (25°C), and elevated (180°C) temperatures. The room temperature mechanical behavior 
indicated that the tensile failure load increased with decreasing heat input, i.e. decreasing tool rotational rate and increasing 
welding speed, such that a maximum failure load was obtained for operational conditions of 1000 rpm and 20 mm/s. This 
tendency in the failure load was also apparent for all the temperatures tested in this work. Compared to the room temperature 
condition, however, the fracture strengths decreased at both low and high temperatures, probably due to the relatively brittle 
and ductile behaviors demonstrated, respectively. The fracture modes were further detailed by using fractographic analysis.  
Paper No.: 8322  
Y. N. Zhang, National Research Council Canada ? Aerospace; X. Cao, National Research Council Canada ? Aerospace; P. Wanjara, 
National Research Council Canada ? Aerospace;  
A continuous wave 5 kW fibre laser welding system was used to deposit Waspaloy filler wire on Inconel 718 substrates. The 
single-bead, multi-bead, and multi-layer deposits were evaluated in terms of macrostructure, microstructure and defects in 
both the as-deposited and post-clad fully heat treated conditions. The main defects observed in the Wapaloy deposits include 
porosity, strain-age cracking and liquation cracking. Deposits without porosity could be obtained with optimized fiber laser 

Speakers’ List 
Version: May 1, 2014 
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deposition parameters. Re-heating during direct laser deposition and/or post-clad heat treatment resulted in the appearance 
of strain-age cracks, which are commonly observed for Waspaloy alloy during welding. By contrast, the liquation cracking was 
healed after post-clad heat treatment. These results indicate that the direct laser process for depositing Waspaloy filler wire 
on Inconel 718 substrates has good potential for the re-manufacturing of superalloy components for aerospace applications.  
Paper No.: 8340  
Paper Title: INVITED: On the understanding of aluminum grain refinement by Al-Ti-B type master alloys  
Xiaoming Wang, Purdue University; Qingyou Han, Purdue University;  
Al-Ti-B type master alloys have been widely used in the grain refinement of aluminum since 1940s. The introduction of Al3Ti 
and TiB2(AlB2) particles reduces the grain sizes down to about 200 micrometer level and makes cold work possible. However, 
the mechanism for the grain refinement is still not clear, though it is believed that TiB2 in the presence of Al3Ti nucleate alpha 
aluminum grains in solidification. This paper presents our finding on the formation of (Ti,Al)B2 solid solution, which leads to a 
proposed theory on grain refinement by Al-Ti-B type master alloys that upon addition into aluminum melt stable TiB2 
particles react with aluminum slowly and release titanium into the melt. The titanium thus released in combination with 
titanium in the melt through dissolution of Al3Ti maintains a transient titanium-rich layer on the surface of (Ti,Al)B2. This 
layer offers a low crystal mismatch with alpha aluminum and promotes the nucleation of aluminum grains.  
Paper No.: 8344  
Paper Title: INVITED: Improved Transient Liquid Phase Bonding of Single Crystal Aerospace Superalloys  
Olanrewaju A. Ojo, University of Manitoba;  
The single crystal (SC) aerospace nickel-base superalloys developments that have occurred in the past two decades have not 
been matched by adequate understanding of appropriate techniques for joining and repairing components made from these 
extremely difficult-to-weld materials by conventional fusion welding processes. Transient liquid phase (TLP) bonding has 
evolved as an attractive alternate joining technique for difficult-to-weld structural materials. Unfortunately, commercial 
exploitation of this technique has been severely limited due to excessively long processing time that is required to produce a 
reliable high temperature joint. In this research, numerical simulation coupled with careful experimental analysis was used to 
study how to reduce the processing time during TLP bonding of SC nickel-base superalloys without the detrimental formation 
of misoriented stray-grains in the joint. The results of the research show that this can be effectively achieved through 
appropriate use of composite powder as interlayer material, which had been previously considered unfeasible for SC 
materials, and this finding will be presented and discussed.  
Paper No.: 8394  
Paper Title: INVITED: Magnetic pulse welding as competitive tool for joining of aluminum to steel sheets  
MANOGARAN Arun, Ecole Centrale Nantes; MARYA Surendar, Ecole Centrale Nantes; RacineuX Guillaume; Ecole Centrale 
Joining of dissimilar metals is a challenging assignment when, coupled with difference in their physical and mechanical 
properties, intermetallic phases are formed. Aluminum and steel offer this challenge as they differ heavily in their melting 
temperatures and inter-diffusion leads to intermetallic compounds of nil or very limited ductility. Fusion welding is impossible 
unless a filler material, compatible from metallurgical standpoint both with aluminum and iron is used. Solid state welding 
processes like diffusion bonding, friction stir welding or linear friction welding remain possible but are slow enough to meet 
productivity criterions of industry such as in automotive. High-speed processes operating in solid phase are required and 
magnetic pulse welding offers one such alternative. In magnetic pulse welding by using an inductor coil through which a heavy 
transient current is discharged, strong magnetic fields are produced. When within these fields, i.e., close to the inductor coil, a 
work piece like aluminum is placed, opposing magnetic fields are produced and if the inductor coil is stiffly fixed, the work 

Speakers’ List 
Version: May 1, 2014 
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piece (Al) is projected away and after impact with the stationary part (steel for instance), explosive like welding is produced. 
One of the constraints for sheet metal welding remains the necessity of maintaining an air gap between Al and steel sheets, as 
the flyer part (Al) must get accelerated to impact the stationary steel part. The maintenance of this air gap is a problem in 
industrial applications. To solve this problem, one of the sheets was stamped locally and placed in close contact with the steel 
plate/sheet. Two sheets are in permanent contact except at stamped regions, where air gap is optimized to generate a local 
spot weld between the two parts. This is a new approach to the joining of Al to steel sheets. The paper will present the 
methodology of joining AA1199 Al to EN 355 steel and detail the characteristics of the spot welds through metallographic 
investigations and mechanical tests.  
Paper No.: 8548  
Paper Title: Progress on stainless steel as bipolar electrode plate material for PEM fuel cells Proton exchange 
membrane (PEM) fuel cells generate electricity by reacting hydrogen and oxygen  
Selcuk Kuyucak, CANMET Materials; Fateh Fazeli, CANMET Materials; Renata Zavadil, CANMET Materials;  
A thin, bipolar electrode material provides a medium for electron exchange with the electrolyte, alternately serving as anode 
at the hydrogen-rich side and cathode at the oxygen-rich side. Stainless steels have sufficient corrosion resistance to qualify as 
bipolar plate. However, the protective chromite layer increases the electrode contact resistance, the battery's internal 
resistance; and thus, decreases the electrical efficiency of the fuel cell. A heat-treatment is proposed and investigated via 
simulation by ThermoCalc / Dictra and experimentally, to generate a sufficient quantity of conducting carbides that breach the 
protective layer. Once carbide growth is arrested, a subsequent heat-treatment is also needed at a higher temperature to 
restore the corrosion resistance by filling-in the Cr-depleted layer (sensitization) around the carbide particles.  
Paper No.: 8549  
Paper Title: INVITED: Friction Stir Processed Powder Metallurgy Aluminium Matrix Composites  
Allison Nolting, DRDC Atlantic Research Centre; C. Munro, DRDC Atlantic Research Centre; A. Gerlich, DRDC Atlantic Research 
Centre ; H. Izadi, DRDC Atlantic Research Centre; P. Bishop, DRDC Atlantic Research Centre;  
Powder metallurgy billets fabricated from Alumix 431D and 4 to 20 vol. % Grade 800 SiC powder were subjected to a single 
pass with a friction stir processing (FSP) tool. Optical and scanning electron microscopy indicated that the friction stir 
processing broke up agglomerated ceramic particles, decreased porosity and increased homogeneity of the ceramic particle 
distribution. Hardness values increased by as much as 40% after friction stir processing. The SiC content at which peak 
hardness occurred increased from 8 vol. % for the unprocessed billets to 16 vol. % for the friction stir processed billets.  
Paper No.: 8553  
Paper Title: INVITED: An Integrated Framework for Multi-scale Multi-physics Modelling of Welding  
Hongbiao Dong, University of Leicester;  
An integrated framework for multi-scale multi-physics modelling of welding has been developed by MIntWeld Consortium in 
Europe. The MIntWeld project ( Modelling of Interface evolution in advanced Welding) is a 4-year international collaborative 
research project funded by the European Commission under their FP7 programme. The consortium developed a numerical 
toolbox which can be used to predict the evolution of interfaces during welding. There are various interfaces involving 
multiple phenomena and different spatial scales, which can be simulated using corresponding numerical modelling methods 
respectively. The modelling methods include quantum dynamics, molecular dynamics, phase field, phase field crystal, 
computational fluid dynamics, phase transformation and heat transfer, thermodynamics, continuum mechanics and 
component life prediction. The MIntWeld consortium designed a common framework which couples each models with the 
upstream and/or downstream models at the relevant neighbouring length scales. Typical examples addressing the remaining 
challenges, such as those of data interpolation between one discretisation of the computational domain and another, are 


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