Jerzy A. Szpunar

• DSci; PhD; MS
• Professor (Full) at University of Saskatchewan

UO2-Molybdenum (Mo) composites are being considered for Accident Tolerant Fuel (ATF) applications in commercial nuclear reactors. In this study, UO2-10 vol% Mo was fabricated using Spark Plasma Sintering (SPS), where the particle size of Mo was varied between 30 nm, 60 nm, 100 nm and 150 µm, to study its effect on the densification of the UO2-10 vo...

The microstructure of pipeline steels plays an important role in determining their resistance to corrosion. Among various microstructural features, grain size has been a topic of ongoing debate regarding its influence on the corrosion resistance of pipeline steels. While it is established that grain size inversely correlates with yield strength, it...

The safe transportation of large volumes of hydrogen gas is crucial for a hydrogen-based economy, with low-carbon steel pipelines at high pressures being the most economic option. However, the risk of hydrogen embrittlement poses a significant challenge, requiring conservative operating limits that reduce their viability. To facilitate steel testin...

The effects of hydrogen diffusion parameters, influenced by microstructural features such as non-metallic inclusion content and ferrite grain size, on the hydrogen embrittlement behavior of X80 and X70 pipeline steels were evaluated by slow strain rate tensile tests. The microstructural characterization was done by field emission scanning electron...

Cerium dioxide (CeO2) finds extensive utility in electro ceramics applications, including solid oxide fuel cells, oxygen sensors, and catalysts. However, Spark Plasma Sintering (SPS) of CeO2 presents challenges due to the increased mobility of O²⁻ ions in the presence of an electric field, as well as its reactivity with graphite tooling. Traditiona...

In the present study, the effect of the welding current parameter on the microstructure, hardness, and mechanical properties of the dissimilar resistance spot welding of the advanced high-strength steel DP590 and the interstitial free steel DC06 was studied. Microstructural examinations were performed on the welded samples using optical microscopy...

The quest for a smooth transition from fossil fuels to clean and sustainable energy has warranted studies on alternative energy materials. Herein, we report on an experimental and theoretical study focused on hydrogen generation through the hydrolysis of microcrystalline cellulose (MCC) treated in different media (deionized water, sodium hydroxide)...

Research and test reactors often use dispersion-type fuel due to its increased thermal conductivity and burn-up capabilities compared to conventional fuel. Al-U 3 O 8 (aluminumtriuranium octaoxide) dispersion fuels have several advantages over their competitors, such as higher service temperature and better stability of oxygen stoichiometry. Howeve...

In the present study, effect of a post-weld intercritical annealing (PWIA) on the microstructure and micro-texture of a friction stir-welded DP600 steel was investigated by means of optical microscopy and electron backscatter diffraction. For this purpose, DP600 steel sheets were butt-welded together using friction stir welding. The weldment was th...

Cerium dioxide (CeO 2 ) finds extensive utility in electro ceramics applications, including solid oxide fuel cells, oxygen sensors, and catalysts. However, Spark Plasma Sintering (SPS) of CeO 2 presents challenges due to the heightened mobility of O ²⁻ ions in the presence of an electric field, as well as its reactivity with graphite tooling. Tradi...

This work examines the effect of stress-relief (SR) and quenching and tempering (QT) heat treatments on the hydrogen-induced cracking (HIC) susceptibility of pipeline steels. Two trials of a similar X65 pipeline steel were used in this study. They had distinct differences in microstructural characteristics, which significantly affected their cracki...

This study uses plane wave density functional theory (DFT) to investigate the effect of certain metal carbides (Niobium carbide, Vanadium carbide, Titanium carbide, and Manganese sulfide) on hydrogen embrittlement in pipeline steels. Our results predict that the interaction of hydrogen molecules with these metal carbides occurs in the long range wi...

The study reports the effect of some metal carbides (niobium carbide, vanadium carbide, titanium carbide, and manganese sulfide) on hydrogen embrittlement in the pipeline industry using plane wave’s density functional theory (DFT). Our results predicted that the interaction of hydrogen molecules with these metals carbide occurs in the long range wi...

Several environmental challenges such as corrosion, low temperature, hydrogen-induced cracking (HIC), stress corrosion cracking (SCC), sulfide stress corrosion cracking (SSCC), and various other failure mechanisms contribute to the deterioration of the mechanical properties of pipeline steels, ultimately resulting in failure. In this review, divers...

In this research, the efficacy of specific heat treatment procedures in mitigating hydrogen embrittlement in X100 pipeline steels is discussed. The studied steels underwent a one-step austenitization process at temperatures of 780 °C (HT1), 830 °(HT2), and 880 °C (HT3) for 90 min, followed by oil quenching, tempering at 600 °C, and air cooling. The...

In this study, the effect of unidirectional accumulative roll bonding (UARB) and rotational ARB (RARB) on the microstructure, texture, and mechanical properties of AA1050 sheets was investigated. The X-ray diffraction technique was used to study the microstructural and textural evolutions in the processed samples. It was found that the successive s...

Accumulative roll bonding (ARB) was carried out via unidirectional (UARB) and cross (CARB) routes to investigate the role of strain path variation on the microstructure, texture, and mechanical properties of commercially pure Al sheets. The microstructure and crystallographic texture were studied using the X-ray diffraction method. Microstructural...

Thorium dioxide (ThO2)-silicon carbide (SiC) composite fuel pellets were fabricated via the spark plasma-sintering (SPS) method to investigate the role of the addition of SiC in enhancing the thermal conductivity of ThO2 fuel. SiC particles with an average size of 1µm in 10 and 15 vol% were used to manufacture the composite pellets. The changes in...

In this study, the hydrogen embrittlement and corrosion behavior of X100 pipeline steel (Ref) was investigated after various heat treatments, including one-step austenitizing at 880 °C (HT3), 830 °C (HT2), and 780 °C (HT1) for 90 min, oil quenching to room temperature, tempering at 600 °C for 30 min, and air cooling to room temperature. Potentiodyn...

Owing to the application of high-strength low-alloy (HSLA) steels and their welded joints in the steel structure of buildings, developing reliable predictive equations for their mechanical properties at elevated temperatures and fire conditions are a matter of great concern. The present study examined the tensile behavior of S900 HSLA steel and its...

The microstructure and micro-texture in different areas of a friction stir (FS)-welded DP600 steel were investigated by means of electron backscatter diffraction. The volume fraction of martensite and non-polygonal ferrite was evaluated based on the image quality (IQ) parameter. Analysis of grain boundaries revealed that the fraction of sub-grain b...

The focus of this work is hydrogen storage in pristine cellulose, chitosan, and cellulose. Chitosan doped with magnesium, titanium, and niobium is analyzed using spin unrestricted plane-wave density functional theory implemented in the Dmol³ module. The results of this study demonstrate that hydrogen interaction with pure cellulose and chitosan occ...

Three different heat treatments were applied on X70 pipeline steel: below transformation temperature (X70-720), in the intercritical temperature range (X70-780), and in the intercritical temperature + tempering (X70-780/720). Then, cathodic hydrogen charging was conducted on these heat-treated samples to study the effect of hydrogen ingress on the...

This paper presents the results of experimental and in-service observations of the nucleation and growth of hydrogen-induced cracking (HIC) in hydrocarbon transport pipelines made of type API 5L steel. The experimental work was done by inducing HIC on steel plates by electrochemical cathodic hydrogen charging and using a straight beam ultrasonic in...

The microstructure evaluation and phase transformation of multi-pass friction stir-processed (FSP) commercially pure titanium were investigated using optical microscopy, scanning electron microscopy equipped with a backscatter detector, and electron backscatter diffractometer. The microstructure characterization shows that the grain refinement mech...

Nowadays, an increasing number of oil and gas transmission pipes are constructed with high-strength low alloy steels (HSLA); however, many of these pipelines suffer from different types of hydrogen damages, such as hydrogen-induced cracking (HIC). So many research efforts are being carried out to reduce the detrimental effects of hydrogen damage in...

We compared the electronic heat capacity coefficient, thermal conductivity and resistivity of ThN and ThC. We found that the electronic heat capacity coefficient of both compounds was very low as evaluated using Quantum Espresso and GGA of the Perdew, Burke, and Ernzerhof (PBE) functional. The calculated electronic heat coefficient was further redu...

One of the most critical issues affecting the integrity of nuclear fuel cladding tubes is hoop stress-induced hydride reorientation from the circumferential to the radial direction. The theoretical prediction of the threshold stress for the hydride reorientation is a long-standing but unrealized objective of material-design engineers in the nuclear...

Hydrogen production, storage, and transportation are the key issues to be addressed to realize a so-called clean and sustainable hydrogen economy. Various production methods, storage methods, and hydrogen transportations have been listed in the literature, along with their limitations. Therefore, to summarize the state of the art of these proposed...

The factors affecting hydrogen trapping at the non-metallic inclusions (NMIs) are identified by a combined experimental and theoretical study. The calculated results based on the proposed models show that the hydrogen trapping capacities at the NMIs decrease in the order of EbTiC>EbTiN>EbAl2O3>EbFeO>EbMnS. The interfacial sinking of hydrogen leads...

The influence of quenching temperature on microstructural and mechanical properties of low alloy steel of the following chemical composition: 0.26 C, 1.70 Mn, 1.42 Si, 1.10 Cr, 1.10 Ni, 0.94 Cu, 0.24 Mo, 0.1 V, Bal. Fe (Wt.%) was investigated after applying a quenching-partitioning (Q-P) treatment. The steel samples were isothermally quenched at 26...

For some decades, the resources within the northern hemisphere have been studied for possible exploration and commercial activities. The need for reliable infrastructures in such extreme cold climatic condition is constantly on the rise. There is an imminent need to develop pipeline steels that can retain good characteristics under extremely low te...

In welding of high-strength steels by conventional methods, it is essential to preserve the strength and ductility close to the base material. The primary focus of this research was to investigate the electron backscattered diffraction (EBSD) characteristics in the coarse grain heat-affected zone (CGHAZ) of S900 base material and correlate them wit...

Evolution of the texture of an Al-Cu composite after addition of alumina particles was investigated in details using X-Ray Diffraction (XRD) method. Composite samples were produced by the Accumulative Roll Bonding (ARB) and alumina particles were uniformly added to the composite using anodizing technique. The process was accompanied by cutting, sta...

Improvement of nondestructive inspection techniques has allowed more frequent detection of closely spaced zones of non-metallic inclusions in pressure vessels made of low carbon steel. In the present study, closely spaced inclusions in an in-service cylindrical horizontal pressure vessel were detected by Scan-C ultrasonic inspection and considered...

Two different thermo-mechanical controlled process procedures were utilized to modify the microstructure and texture of pipeline steel. Moreover, electrochemical hydrogen charging and hydrogen permeation experiments were used to investigate the effect of texture and microstructure on the HIC susceptibility of tested specimens. The results showed th...

Uranium dioxide (UO2)−molybdenum (Mo) composites have been proposed as accident tolerant fuel candidates due to their high thermal conductivity, high melting point, high boiling point, and ability to have low thermal neutron absorption cross-section. It is therefore essential to evaluate the method of fabrication and thermophysical properties of th...

The aim of this study is to investigate the fracture surfaces and crack propagation in an API X70 pipeline steel in acidic environment. To this purpose, as-received and electrochemically hydrogen-charged tensile specimens are subjected to tensile testing. Moreover, EBSD measurements were carried out on the cross section (RD-ND plane) in as-received...

SEM and EBSD techniques are used to evaluate hydrogen induced cracking susceptibility in API X70 pipeline steels produced by thermo-mechanical controlled process (TMCP) in laboratory scale. Based on the observations, there is no dominant texture in the specimens and the grains are randomly distributed. Different TMCP parameters and rolling processe...

This study assesses the effect of microalloying additions and thermomechanical processing on the mechanical properties of four pipeline steels. The investigated steels had quite similar processing conditions, with some small differences, in niobium (Nb) content. The surface and center layers of the steels were characterized after thermomechanical p...

In this study, a comparative analysis of fracture surfaces in API X60 and API X60SS pipeline steels is carried out after hydrogen charging followed by tensile testing. The JIS test setup is also utilized in order to measure the amount of discharged hydrogen through the microstructure of both steels. EBSD measurements are also done on as-received an...

In this study, texture development during the accumulative roll bonding (ARB) of Al-Cu multilayered composite was investigated using X-ray diffraction. Microstructural investigations were also conducted using optical and transmission electron microscopy. The results of textural investigation of the rolled specimens indicated that a strong β-fiber w...

In this investigation, we prepared samples with five different grain misorientations by cold-rolling an X70 pipeline steel plate. The hydrogen permeation and hydrogen visualization experiments were used to compute the diffusion parameters and to reveal the diffusion path in steel samples. The dual-polarized permeation experiment allowed us to show...

The aim of this study is to investigate the microstructure and mechanical properties of friction stir welded super duplex stainless steels. In this regard, UNS S32750 steel is joined by friction stir welding (FSW) method. The tool used in this research is made of WC with 16-mm shoulder diameter and 5-mm pin diameter. Microstructural investigations...

Iranian Journal of Materials Forming: A commercial Al-Mg-Si alloy (AA 6061) was deformed by using the accumulative roll bonding (ARB) process for up to five cycles at ambient temperature. The evolution of texture in this process was studied by the X-ray diffraction (XRD) method. Experimental results indicate that the combination of the shear textu...

Heat treatment is suggested as a means of improving microstructural properties for steels. Three API 5L X65 pipeline steels were subjected to a variety of quenching rates in brine and oil after heating up to 800°C. Thereafter, tempering was performed at a lower temperature of 550°C. Quenching the steels at a slower rate in oil generated refined mic...

Microstructure and microtexture of a dual-phase (DP) steel was investigated using the electron backscattered diffraction (EBSD) technique. A DP600 steel was produced by 60% cold-rolling a low carbon steel with an initial ferrite pearlite microstructure followed by intercritical annealing at 720°C for 1 h. Kernel average misorientation map of the DP...

The microstructure of the fuel pellet plays an essential role in fission gas buildup and release and is critical for the safe and continued operation of nuclear power stations. Structural analysis of uranium dioxide (UO2)–molybdenum (Mo) composite fuel pellets prepared at a range of sintering temperatures from 1300–1800 oC was performed. Mo micro a...

This research aims to evaluate the effect of weld pitch on the microstructure and properties of St 37/AISI 316 steels friction stir welds. The microstructure and microtexture of the samples were studied by means of electron backscatter diffraction analysis. The mechanical behaviors of the weldments were also investigated by microhardness, shear pun...

The aim of this work was to characterize the microstructure-mechanical response relationships in UNS N08825/AISI 316L welds by means of electron backscatter diffraction analysis. Welding was conducted by ERNiCrMo-3 and ER308L filler wires. It was indicated that a significant increase in fractions of low Σ coincidence site lattice (CSL) boundaries o...

We compared the heat capacity and thermal conductivity of ThN calculated using ab initio methods versus recently published porosity-free experimental data. The experiments provided only a cumulative contribution from phonons and electrons; the problem thus presented was how to distinguish between each contribution and the new correlations were deve...

The precipitation behavior during equal-channel angular pressing (ECAP) performed at 400°C in an Al-Si-Cu alloy has been investigated. Meanwhile, grain refinement and tensile properties of solution-treated A390 Al alloy have been studied under various ECAPed passes. Microstructural results showed that during the solution treatment, the high volume...

Theoretical and experimental studies with focuse on hydrogen generation through thehydrolysis of graphene oxide (GO) functionalized with magnesium (GOMg), titanium(GOTi), and niobium (GONb) were performed. Thermogravimetric (TGA) results revealvariable thermal decomposition profiles for the composites, in agreement with thedecomposition of the labi...

In automotive industries, employing advanced high-strength steels such as dual-phase steels by taking advantage of high dynamic force absorption during car accidents and lightweight is one of the major challenges. In this regard, the effect of resistance spot welding parameters on the above great properties of advanced high-strength DP590 steel has...

A new facile approach for preparing two nonfluorinated hybrid organic-inorganic siloxane/polydimethylsiloxane nanocomposite coatings for cotton fabrics is presented using two distinct silylating agents. The first coated fabric was prepared predominantlyviatrimethylsilyl modification using hexamethyldisilazane (HMDS) while higher amounts of trimetho...

The development of high-strength pipeline steels with low susceptibility to hydrogen embrittlement (HE) is essential in the energy industry. Studies focusing on the HE of steels often results in contradicting findings due to the complex connection between hydrogen behavior and other material characteristics such as microstructure, chemical composit...

Al-18%Si-4.5%Cu alloy was processed by route BC equal-channel angular pressing (ECAP) at a temperature of 400 °C. Electron backscattered diffraction (EBSD) was used to analyze the microstructure and microtexture during the ECAP process. The microstructural results showed three important effects: First, the particle-stimulated nucleation (PSN) and c...

In this study, the microstructure, tensile properties, and the fracture behavior of hypereutectic A390 aluminum alloy produced by route BC of equal channel angular pressing (ECAP) were investigated. Microstructural observations showed that the microstructure of the A390 alloy was considerably improved by the ECAP. After the fourth pass, most of the...

Chitosan derivatives are easily synthesized since their amine-bound glucosamine molecular units allow for the introduction of reactive chemical groups within their linear polymer chains. These compounds acted as green corrosion...

In this article, a theoretical and experimental investigation on the phonon thermal conductivity (κL) of α-U3O8 in the temperature range of 300 K to 1000 K is reported. The theoretical calculations of the κLwere performed via the density functional theory (DFT) unified with the Boltzmann transport equation (BTE). An extensive investigation of the m...

An in-depth understanding of the role of non-metallic inclusions (NMIs) in the hydrogen-induced failure of structural materials is important in the manufacture and application of steels. In this paper we investigated the type, the amount and the distribution of NMIs in pipeline steels and their relation to the susceptibility to hydrogen-induced cra...

Nickel superalloy Hastelloy-N, alloy X-750, stainless steel 316 (SS316), and stainless steel 304 (SS304) are among the alloys used in the construction of molten salt reactor (MSR). These alloys were analyzed for their corrosion resistance behavior in molten fluoride salt, a coolant used in MSR reactors with 46.5% LiF+ 11.5% NaF+ 42% KF. The corrosi...

In this study, the microstructural features and microtexture evolution of API X-65 steel welded to UNS S32750 stainless steel were evaluated. The weldments were produced with the different heat input (HI) values: 0.68 and 0.78 kJ/mm. The samples were then characterized by means of the electron backscatter diffraction analysis. The obtained results...

SAF 2205 and IN X-750 were joined using the TLP method. The joining process was carried out at 1100 °C for different times using BNi-3 interlayer. Microstructural study and identification of the present phases in the bonding regions were performed using optical microscopy and scanning electron microscopy equipped with energy-dispersive X-ray spectr...

Readers should note that the name of the second author of this article was misspelled (as Morteza Shmanian) in the article as published. The correct spelling of the author’s name is Morteza Shamanian.

In this study, route Bc of the equal channel angular pressing (ECAP) method has been successfully applied to the Al–Si–Cu alloy at 400 °C. Scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) were used to analyze the microstructure. Texture evolution was studied by the X-ray diffraction (XRD) technique. The microstructural...

In this research the microstructure evolution and mechanical behavior of dissimilar weld between AISI 321 stainless steel (SS) and INCOLOY 825 using ERNiCrMo-3 (Inconel 625) filler wire were investigated. Electron back scattered diffraction (EBSD) analysis was used to characterize the weld substructure. The microstructural examination exhibited an...

The development of inhomogeneity in the microstructure, texture, and mechanical property in hot-rolled (API) 5L X70 pipeline steel after rough and finish thermomechanical control processing has been investigated by experimental measurements. Our investigations revealed that the rough rolling stage produced mostly large and coarse ferrite grains acr...

Inclusions are very often founded in the centre of thickness in hot-rolled pipeline steel. In this research, the role of these inclusions on hydrogen diffusion, accumulation and distribution in pipeline steel is studied using the electrochemical permeation and visualisation experiments. While the permeation experiment estimates the parameters of th...

We investigated the electronic heat capacity and energetics of thermal excitations of electrons around Fermi energy of selected metallic compounds (UN, UAl2 and ThN) using first-principles methods. The effect of magnetism was evaluated for UN and UAl2. The generalized gradient approximation (GGA) of the Perdew, Burke, and Ernzerhof functional, deve...