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Speakers’ List 
 
Version: May 1, 2014 
Page 11 of 104 
 
to measure the ultimate tensile strengths of the coach peel SPR joints with different material combinations. Deformation and 
failure of the joints under tensile loading were studied. The normal hypothesis tests were performed to examine the 
rationality of the test data. This work was also aimed at evaluating experimentally and comparing the energy absorption of the 
coach peel SPR joints with different material combinations.  
 
Paper No.: 8443  
Paper Title: Improved mechanical properties of heat treated 7075 aluminum alloy  
Authors:  
Haroon Mehmood Ali, ; Muhammad Ali Asghar, ;  
Abstract 
Abstract: Author : Haroon Mehmood Ali (haroon267@hotmail.com), Ali Asgher, Umar Shaukat A study has been carried out on 
commercial aluminum alloy AA7075. The effects of hot rolling, at different temperatures, after T73 temper were studied in this 
experiment. Alloy 7075 was solution heat treated at 470oC and then subjected to the aging process at 120oC for 16 hours. The 
heat treated samples were hot rolled into the sheets of 2mm thickness. Two temperatures 350o C and 450o C were chosen for 
hot rolling process. The obtained samples were analyzed by using different characterization techniques i.e. optical microscopy, 
Scanning Electron Microscopy (SEM) to study micro-structural changes and formation of inter metallic, and Universal Testing 
Machines (UTM) to characterize mechanical properties of the hot rolled sheets part. Improved mechanical properties were 
obtained for the sheet hot rolled at 450o C. Increase in strength was caused due to the formation of fine grains via 
recrystallization process. Whereas mechanical properties of the sheets, hot rolled at 350o C decreased due to the increase in 
the size of inter-metallic particles.  
 
Paper No.: 8472  
Paper Title: INVITED: Optimization of Die Cooling in the Aluminum Alloy Wheel Casting Process  
Authors:  
Jianglan Duan, University of British Columbia; Carl Reilly, University of British Columbia; Daan Maijer, University of British 
Columbia; Steve Cockcroft, University of British Columbia; Andre Phillion, The University of British Columbia;  
Abstract 
In the aluminum alloy wheel casting process, careful design of the cooling system in the die and its operation (cooling channel 
timing) are critical to achieve quality and productivity goals. The problem is challenging owing to the cyclic nature of the 
process and the relatively large thermal mass of the die in comparison to the wheel. For a given die geometry, a set of 
constraints have been defined to ensure directional solidification and an objective function, based on cooling rate during 
solidification, has been defined to reach a target secondary dendrite arm spacing. The methodology presented in this study 
employs the commercial finite element package, ABAQUSTM, and an optimization module based on the open source library, 
Scipy. The developed methodology has been applied to a series of geometries and cooling system configurations, including a 2-
D axisymmetric wheel and die assembly generated from a prototype die. Preliminary testing has shown that careful selection 
of the objective and constraint functions have made it possible to reach desired solidification pattern.  
 
Paper No.: 8503  
Paper Title: INVITED: Analysis of Microstructural Changes in the Heat-Affected Zone and Fusion Zone of a Fiber Laser 
Welded DP980 Steel  
Authors:  
Jianqi Zhang, University of Manitoba; Abdul K. Khan, University of Manitoba; Olanrewaju Ojo, University of Manitoba; Norman 
Zhou, University of Waterloo; Daolun Chen, University of Ryerson;  
Abstract 
Dual phase (DP) steels were designed to consist of hard martensite dispersed in a relatively soft ferrite matrix, which offered a 
favorable combination of high strength with good deformability. During manufacturing, welding is an essential process. Fiber 
laser welding (FLW) is becoming increasingly important due to its flexibility and deep penetration. However, the rapid 
thermal cycle involved in the FLW generates microstructural changes in the heat-affected zone (HAZ) and fusion zone (FZ) of 
DP steels, which could significantly affect the subsequent mechanical properties. The fine martensitic structure in the FZ and 
large variation in microstructure in the narrow HAZ made it very difficult to properly elucidate microstructural changes that 

 
Speakers’ List 
 
Version: May 1, 2014 
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occurred during the FLW. In this study the microstructural changes that occurred in the narrow HAZ and FZ were 
systematically studied by the use of Gleeble thermo-mechanical simulation system and transmission electron microscopy 
(TEM). It was observed that significant microstructural changes occurred in the FZ and upper-critical HAZ, which could result 
in dramatic changes in mechanical properties. The microhardness of the FZ and adjacent HAZ were notably disparate from 
that of the base metal (BM). Detailed results that are indicative of microstructural changes during the FLW of DP980 steel will 
be presented.  
 
Paper No.: 8512  
Paper Title: INVITED: Effect of Porosity on Fatigue Crack Initiation and Propagation of High Pressure Die Casting AM60 
Magnesium Alloy  
Authors:  
Zhuofei (Felix) Yang, McMaster University; Jidong Kang, CANMET, Materials; David S. Wilkinson, McMaster University;  
Abstract 
High pressure die casting magnesium alloys are increasingly being used for automotive applications. Shrinkage voids are often 
seen in microstructure of these alloys thus raises concerns on the effect of porosity on mechanical properties including fatigue 
performance. However, traditional non-destructive techniques such as X-ray radiography or ultrasound are hardly to measure 
voids in the sub-millimeter range. In this contribution, the effect of porosity on fatigue crack initiation and propagation of an 
AM60 high pressure die casting was studied using X-ray computed tomography (XCT) technique and full-reversed strain 
controlled fatigue testing at an amplitude of 0.3% total strain. 3D spatial distribution of shrinkage voids and its evolution was 
followed prior to and during the testing. Fatigue test was interrupted every 20, 00 for XCT-scans to detect porosity evolution 
and possible crack initiation and propagation until macroscopic cracks are visualized on the specimen surface. The results 
show that fatigue crack usually initiates at the machined side surface where large-volume pores lie underneath and then 
perpendicularly propagates into specimen. During its propagation, crack becomes thicker and wider. Void linkage with cracks 
is seen in the specimen but no apparent void growth was found during the fatigue testing.  
 
Paper No.: 8517  
Paper Title: INVITED: Ultrasonic Processing of Materials  
Authors:  
Qingyou Han, Purdue University;  
Abstract 
Irradiation of high energy ultrasonic vibration in metals and alloys generates oscillating strain and stress fields in solids, and 
introduces nonlinear effects such as cavitation, acoustic streaming, and radiation pressure in molten materials. These 
nonlinear effects can be utilized to assist he conventional materials processing processes. This article describes recent 
research at Purdue University using high intensity ultrasonic vibrations for deagssing molten aluminum, processing 
particulate reinforced metal matrix composites, refining metals and alloys during solidification process, and producing bulk 
nanostructures in solid metals and alloys.  
 
Paper No.: 8524  
Paper Title: Development of new Erbia-doped Yttria Stabilized Zirconia solid solutions via Spark Plasma Sintering 
route  
Authors:  
Christopher James Verdon, University of British Columbia; Lukas Bichler, University of British Columbia;  
Abstract 
Yttria stabilized zirconia (YSZ) ceramics are used in diverse applications ranging from solid oxide fuel cells to thermal barrier 
coatings on turbine blades, to oxygen sensors in automotive applications. In the nuclear industry YSZ is used as a thermal 
insulator, it can experience issues related to corrosion and high temperature degradation. Doping of YSZ with oxides (e.g., 
CeO2, La2O3, Nd2O3) is beneficial for enhancing the room temperature properties of YSZ. Literature suggests that erbia 
(Er2O3) doped alumina ceramics exhibit excellent creep resistance and chemical inertness. However, there is no literature on 
the effect of Er2O3 doping of YSZ. In this work, the effect of doping YSZ with 5, 10 and 15 mol% erbium oxide (Er2O3) was 
investigated using spark plasma sintering (SPS) technique. Sintering was carried out at 1200, 1300, and 1400°C, with 30, 60, 

 
Speakers’ List 
 
Version: May 1, 2014 
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and 70 MPa uniaxial pressures. Densification kinetics were studied using displacement response from SPS tooling. As- sintered 
microstructure characterization was carried out via scanning electron microscopy and X-ray diffraction. ANOVA analysis was 
also used to relate microhardness to the as-sintered microstructure, and most influential process parameters were identified.  
 
Paper No.: 8580  
Paper Title: Carbon content and heat treatment effects on microstructures and mechanical properties of 13Cr?4Ni 
martensitic stainless steel  
Authors:  
Aziz Akhiate, École Polytechnique de Montréal, Canada; Elise Braud, École d'ingénieur EPF, France; Denis Thibault, Institut de 
recherche d'Hydro-Québec (IREQ), (QC), Canada; Myriam Brochu, École Polytechnique de Montréal, Canada;  
Abstract 
Cast martensitic stainless steels, 13Cr?4Ni, having carbon contents between 0.018 wt.% and 0.067 wt.% were normalized, air 
quenched, and tempered at two different temperatures (550°C and 610°C). Their microstructures were characterized by 
optical microscopy and X-ray diffraction (XRD). Macro- and micro-hardnesses, tensile strengths, and impact resistance were 
quantified for each material and condition. Results show that the prior-austenite grain size is constant through the materials 
but the percentage of reformed austenite, contained in the martensitic matrix, depends strongly on the material chemistry and 
on the tempering temperature and on its duration. It is observed that, independently of tempering conditions, an increase in 
carbon content increases the material hardness and tensile strengths, whereas the elongation remains constant. In contrast, 
the results of Charpy type impact toughness tests show a different trend. The material containing the average carbon content 
(0.034 wt.%) is significantly tougher than the two other alloys. Surprisingly, the toughness of the steel containing 0.034 wt.% 
carbon was found independent of the reformed austenite content. It is thus concluded that carbon content and reformed 
austenite are not the only parameters affecting the toughness of these steels.  
Stream: Arsenic Metallurgy & the Environment
  
 
Paper No.: 8640  
Paper Title: Reduction of Arsenic and Other Species of Concern in Mining Effluent  
Authors:  
Gioulchen Tairova, Enviramet, Inc; Junian Ioffe, Enviramet, Inc;  
Abstract 
Arsenic, selenium and mercury species are common contaminants in mining aqueous streams and present significant 
environmental and health problems. The objective of this project is to investigate methods to lower the concentrations of 
these elements in mining aqueous streams. A new composite media for removal of these elements of concern from mining 
effluents was developed. The results of bench scale and pilot plant experiments, using the media, indicated removal of arsenic, 
selenium, mercury and other elements of concern below detection limits.  
 
Paper No.: 8641  
Paper Title: PRESSURE LEACHING OF A HIGH ARSENIC COPPER CONCENTRATE UNDER CESL PROCESS CONDITIONS  
Authors:  
Fernando Parada, University of Concepción; I. Wilkomirsky, ;  
Abstract 
A copper concentrate with 26% of enargite was leached in a 3 L autoclave reactor under conditions based on the CESL process. 
The concentrate with a P80 of 48 microns was leached without a regrind and temperature was tested between 150 and 180ºC. 
Copper, arsenic, sulfur and iron were checked in all the experiments and antimony, bismuth, zinc and molybdenum were 
evaluated in selected tests. The 98% of the obtained copper extraction is agree with other authors, but the behavior of arsenic, 
iron an sulfur have some differences. The solid residue was characterized by chemical analysis, DRX and Qemscan. Finally, a 
comparative analysis with roasting treatment for this type of concentrate is presented.  
 

 
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Version: May 1, 2014 
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Paper No.: 8643  
Paper Title: MINERALOCHEMICAL CHARACTERIZATION OF CALCINES AND FLUE DUSTS DURING NEUTRAL ROASTING 
OF ARSENIC COPPER CONCENTRATES IN THE PILOT PLANT OF UNIVERSITY OF CONCEPCIÓN  
Authors:  
F. Parada, University of Concepción; I. Wilkomirsky, University of Concepción; E. Balladares, University of Concepción; Roberto 
Parra, University of Concepción;  
Abstract 
The neutral roasting of As bearing concentrates is one of the most confirmed and promising options for the treatment of this 
type of complex concentrate. The As elimination by volatilization allows the treatment of the calcines produced in a 
conventional pyrometallurgical process, blending this product with standard concentrates. Several tests were performed in 
the fluidized pilot plant in the University of Concepción with different types of concentrates allowing the collection of calcines, 
fines from two hot cyclones and flue dust from ESP. Those materials were characterized using QEMSCAN® and used for the 
development of a mass and balance considering the specific chemical transformation that occurs in the bed. A 
physico?chemical/kinetic model is being proposed to explain the formation of bornite, chalcopyrite and magnetite. The 
mechanism involves solid state- gas and solid?gas reactions between chalcocite, pyrrhotite and gaseous sulfur that without the 
mineralochemical characterization would not been possible to propose  
 
Paper No.: 8642  
Paper Title: TECHNICAL EVALUATION OF THE USE OF WEAK ACID CONTAMINATED WITH ARSENIC IN COPPER HEAP 
LEACHING  
Authors:  
Fernando Parada, University of Concepción; R. Parra, University of Concepción;  
Abstract 
Sulfuric acid plants associated to copper concentrates smelters produce an acid effluent from the gas scrubber. This effluent is 
called weak acid and usually contains 100 to 500 g/l of sulphuric acid, 4 to 10 g/l of arsenic and other minor elements. This 
paper presents the analysis of the utilization of weak acid in a copper heap leaching operation whose mineral contain soluble 
iron (III) which can be used to precipitate the arsenic in a stable form, similar to ferrihydrite process. Lab test results and 
samples from the heap leaching plant showed that a PLS with a Fe/As ratio higher than 50 is obtained and an almost complete 
arsenic precipitation occur in the secondary leaching stage, when the PLS pH reach a value between 2 an 2.5. The solid residue 
with the arsenic was treated with the TCLP test (EPA, toxicity characteristic leaching procedure) showing that the impurities 
level were under the maximum levels to be a hazardous residue.  
 
Paper No.: 8560  
Paper Title: KEYNOTE: Arsenic Immobilization Research Advances: Past, Present and Future  
Authors:  
George Demopoulos, McGill University;  
Abstract 
In this paper the author will provide an overview of over 20 years of research & developments in the area of 
hydrometallurgical arsenic immobilization that culminated recently in the industrial implementation of the atmospheric 
scorodite process. The paper will consider various aspects of arsenic fixation in the non-ferrous metal industry from the iron-
arsenic co-precipitation process employed to arsenic-bearing effluent solutions; to autoclave processing of arsenical copper 
and gold feedstocks and the fate of the in-situ formed iron sulphato-arsenate precipitate phases; the precipitation and stability 
of scorodite; the possible stabilizing role of mineral phases like yukonite, symplesite or svabite; and the development of 
?scorodite-plus? processes employing novel encapsulation strategies. Emphasis is placed on the characterization and long-
term stability of the various forms of arsenic-immobilized phases under either oxic or anoxic conditions over a wide pH range 
and the establishment of critical links between process parameters and hazardous material stability, contributing thus to 
advancement of new generation safe and sustainable waste management technologies.  
 
Paper No.: 8568  
Paper Title: Environmental and Occupation Hygiene Considerations for High-Arsenic Metallurgical Testwork  

 
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Version: May 1, 2014 
Page 15 of 104 
 
Authors:  
Peter Lind, Barrick Gold Corporation; Hamid Ardehali, Barrick Technlology Centre;  
Abstract 
Many gold deposits also contain significant quantities of deleterious elements such as arsenic. Several biological pathways are 
possible for arsenic exposure; special care and caution must be used while undertaking metallurgical testwork on ores and 
concentrates that contain high levels of arsenic. Laboratory precautions pertaining to handling of airborne dust 
concentrations, necessary personal protective equipment, and effluent treatment are discussed.  
 
Paper No.: 8582  
Paper Title: INVITED: TREATING HIGH ARSENIC COPPER CONCENTRATES THROUGH PYROMETALLURGICAL 
PROCESSING  
Authors:  
Patrick R. Taylor, Colorado School of Mines;  
Abstract 
A review of various methods to treat high arsenic copper concentrates through pyrometallurgical processing is presented. 
Examples are drawn from various past and current operations and research. Various aspects of the engineering alternatives 
for treatment methods are discussed. Some of the methods discussed include: controlled oxidation roasting, adaptation of 
some smelter technology to accept higher amounts of arsenic, complete oxidation with arsenic fixation; sulfation roasting; acid 
baking, soda ash roasting, and others methods. Other topics include: a short discussion of other problematic impurities; the 
effects of arsenic on copper electro-refining and product purity; and methods for the ultimate disposal, or marketing, of the 
arsenic. The latest work being done at the Colorado School of Mines on soda ash roasting is also presented.  
 
Paper No.: 8317  
Paper Title: Two-Stage Fluid Bed Reactor for Arsenic Removal and Fixation  
Authors:  
Kamal Adham; Hatch & Associates Ltd.; Chris Harris, Hatch & Associates Ltd;  
Abstract 
Arsenic is often associated with copper, nickel and gold in sulphide deposits. This paper describes a two-stage high-
temperature fluid bed reactor for the removal and fixation of As from ores and concentrates. The first (bottom) stage of 
reactor removes the As through a neutral roast, by volatilization as mostly sulphide species. The second (top) stage of reactor 
captures the As from the gas phase through oxidative fixation, as a stable iron arsenate, by reaction with an appropriate iron 
source (sulphide or oxide). The second stage is placed on top of the first, so that their combined function can be achieved in a 
simple two-stage fluid bed arrangement, with the bottom stage off-gas providing the top stage fluidization.  
 
Paper No.: 8318  
Paper Title: Gold Concentrate Roaster for Sulphur, Carbon and Arsenic Removal  
Authors:  
Kamal Adham; Hatch & Associates Ltd.; Andrew Tohn, Hatch & Associates Ltd; David Lemieux, Nichromet ;  
Abstract 
To remove sulphur, carbon and arsenic from the gold concentrates of Nichromet (now Dundee Sustainable Technologies), 
Hatch has designed a demonstration plant roaster using the fluid bed technology. The fluid bed was selected for its ability to 
maintain stable temperatures and uniform reaction conditions. Data points from a small pilot plant (operated by Nichromet) 
were used for setting the parameters of the demo plant roaster. The Nichromet demonstration plant is being built to further 
prove their patented gold extraction process at a larger scale. Their gold extraction process is based on halogenation at 
atmospheric pressure and relatively low temperatures. Before the halogen leaching, most of the sulphur, carbon and arsenic 
should be roasted out of the feed concentrate. The Hatch fluid bed roaster design includes a moist feed introduction system
simple bed cooling for temperature control, and cyclone fines recirculation. The demonstration plant roaster is planned for 
construction in 2014, and the performance results will be presented in a future paper.  
 
Paper No.: 8337  

 
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Version: May 1, 2014 
Page 16 of 104 
 
Paper Title: Selective metal recovery to offset cost of arsenic removal with sulphide precipitation  
Authors:  
Farzad Mohammadi; BioteQ Environmental Technologies; Patrick Littlejohn, BioteQ Environmental Technologies; David 
Sanguinetti, BioteQ Environmental Technologies;  
Abstract 
Arsenic levels in copper concentrates are increasing with the development of low grade and complex ores. Smelting of these 
minerals generates process water high in dissolved arsenic, copper and often other metals that require treatment prior to 
discharge or re-use. Sulphide precipitation has been tested at a laboratory scale to treat copper smelter effluent containing 
high concentrations of arsenic. In addition to removing arsenic to very low levels, the process can selectively recover dissolved 
metals of appreciable value and reduce waste generation. An overview of the test program, results and preliminary economics 
will be discussed in this paper.  
 
Paper No.: 8392  
Paper Title: Investigation of the Fe2O3-As2O5 Phase Diagram for Arsenic Stabilization During Gold Extraction Process  
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