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Calculations on the global energy consumption due to friction and wear in the mineral mining industry are presented. For the first time, the impact of wear is also included in more detailed calculations in order to show its enormous tribological and economic impacts on this industry. A large variety of mining equipment used for the extraction, haulage and beneficiation of underground mining, surface mining and mineral processing were analysed. Coefficients of friction and wear rates of moving mechanical assemblies were estimated based on available information in literature in four general cases: (1) a global average mine in use today, (2) a mine with today's best commercial technology, (3) a mine with today's most advanced technology based upon the adaptation of the latest R&D achievements, and (4) a mine with best futuristic technology forecasted in the next 10 years. The following conclusions were reached: • Total energy consumption of global mining activities, including both mineral and rock mining, is estimated to be 6.2% of the total global energy consumption. About 40% of the consumed energy in mineral mining (equalling to 4.6 EJ annually on global scale) is used for overcoming friction. In addition, 2 EJ is used to remanufacture and replace worn out parts and reserve and stock up spare parts and equipment needed due to wear failures. The largest energy consuming mining actions are grinding (32%), haulage (24%), ventilation (9%) and digging (8%). • Friction and wear is annually resulting in 970 million tonnes of CO2 emissions worldwide in mineral mining (accounting for 2.7% of world CO2 emissions). • The total estimated economic losses resulting from friction and wear in mineral mining are in total 210,000 million Euros annually distributed as 40% for overcoming friction, 27% for production of replacement parts and spare equipment, 26% for maintenance work, and 7% for lost production. • By taking advantage of new technology for friction reduction and wear protection in mineral mining equipment, friction and wear losses could potentially be reduced by 15% in the short term (10 years) and by 30% in the long term (20 years). In the short term this would annually equal worldwide savings of 31,100 million euros, 280 TWh energy consumption and a CO2 emission reduction of 145 million tonnes. In the long term, the annual benefit would be 62,200 million euros, 550 TWh less energy consumption, and a CO2 emission reduction of 290 million tonnes. Potential new remedies to reduce friction and wear in mining include the development and uses of new materials, especially materials with improved strength and hardness properties, more effective surface treatments, high-performance surface coatings, new lubricants and lubricant additives, and new designs of moving parts and surfaces of e.g. liners, blades, plates, shields, shovels, jaws, chambers, tires, seals, bearings, gearboxes, engines, conveyor belts, pumps, fans, hoppers and feeders. acceptedVersion

Highly corrosion- and wear-resistant thermally sprayed chromium carbide (Cr3C2)-based cermet coatings are nowadays a potential highly durable solution to allow traditional fluidized bed combustors (FBC) to be operated with ecological waste and biomass fuels. However, the heat input of thermal spray causes carbide dissolution in the metal binder. This results in the formation of carbon saturated metastable phases, which can affect the behavior of the materials during exposure. This study analyses the effect of carbide dissolution in the metal matrix of Cr3C2-50NiCrMoNb coatings and its effect on chlorine-induced high-temperature corrosion. Four coatings were thermally sprayed with HVAF and HVOF techniques in order to obtain microstructures with increasing amount of carbide dissolution in the metal matrix. The coatings were heat-treated in an inert argon atmosphere to induce secondary carbide precipitation. As-sprayed and heat-treated self-standing coatings were covered with KCl, and their corrosion resistance was investigated with thermogravimetric analysis (TGA) and ordinary high-temperature corrosion test at 550 °C for 4 and 72 h, respectively. High carbon dissolution in the metal matrix appeared to be detrimental against chlorine-induced high-temperature corrosion. The microstructural changes induced by the heat treatment hindered the corrosion onset in the coatings. acceptedVersion

Localized deformation and cracking in a system of thermally sprayed hard metal coating overlaid on a low alloy steel is studied by means of bend testing. In-situ digital image correlation measurements are used to characterize material strain field near the coating/substrate interface. The studied substrate undergoes softening upon yielding which manifests itself as narrow bands of localized shear deformation. The measurements show that the coating cracks and the substrate shear bands interact. When the coating starts cracking during the elastic loading of the substrate, the formed cracks function as nucleation points for the shear bands. In contrast, if the coating resists cracking until the yielding of the substrate, the coating cracks and substrate shear bands form simultaneously. Based on the experiments, continuum-scale finite element model of the system is developed, validated and then used for a systematic numerical analysis of the effects of substrate shear banding on the measurement of coating properties. Based on the results of this work, three main effects can be identified. Firstly, the flow localization in the substrate can increase the measured apparent (macroscopic) surface strain of the coating, if not accounted for by using microscopic techniques. Secondly, substrate shear bands increase the interfacial loading, which may cause unexpected delamination of the coating and thus affect the evaluation of the interfacial strength. Finally, substrate shear bands affect the stress state within the coating and may thus affect the cracking morphology in the coating. Therefore, based on the results of this study, if the coating and interfacial strengths are of similar magnitude with the substrate yield strength, the possible tendency of the substrate towards flow localization should be taken into account in the analysis of the coating behavior. acceptedVersion

There is direct link between non-idealities in fretting wear, friction and fretting fatigue, especially in the case of adhesion spots. Friction is not a constant and varies as a function of load cycles and non-Coulomb friction may occur. Fretting wear may lead to material transfer, resulting in tangential fretting scar interactions, and in the long run, wear debris is entrapped and cumulated in the interface. Fatigue failure can occur at low nominal stress amplitudes due to non-Coulomb effects. Novel tools are required in component design to fully capture these non-ideal phenomena. publishedVersion

This paper presents an investigation into the effect of unexpected overloading on scuffing initiation with a twin-disc test device. An existing twin-disc test device was modified to be suitable for applying overloading dynamically to the disc contact. Three test series including three pairs of discs in each series were subjected to combined normal force and rolling/sliding loading. First a base level for scuffing initiation was defined by increasing the normal load stepwise until failure, while keeping the rolling and sliding between the discs constant. In the subsequent test series, the overload cycles were applied at a significantly lower level in two different patterns leading to scuffing at both an earlier and later stage than was observed for the base level. acceptedVersion

Dielectric elastomers are materials often utilized for the fabrication of electroactive actuators. Acrylic rubber (ACM) is very widely used in dielectric elastomer actuators (DEAs). However, its overall good performance is limited by the high operating electric field required. In the present work, we compare the effect of different types of conventionally used carbon black (CB) as well as other carbon-based fillers on the dielectric and actuation properties of ACM in order to show that performance of DEAs can be improved by the development of ACM composites. Indeed, addition of CB, carbon nanotubes (CNTs), and synthetic graphite leads to an increase in the relative dielectric permittivity of elastomeric material. Moreover, incorporation of nanodiamonds results in reduction of dielectric losses. Finally, actuation stress is remarkably improved by CNTs and different grades of CB. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers

High-velocity impact wear can have a significant effect on the lifetime of thermally sprayed coatings in multiple applications, e.g., in the process and paper industries. Plasma-sprayed oxide coatings, such as Cr2O3- and TiO2-based coatings, are often used in these industries in wear and corrosion applications. An experimental impact study was performed on thermally sprayed ceramic coatings using the High-Velocity Particle Impactor (HVPI) at oblique angles to investigate the damage, failure, and deformation of the coated structures. The impact site was characterized by profilometry, optical microscopy, and scanning electron microscopy (SEM). Furthermore, the connection between the microstructural details and impact behavior was studied in order to reveal the damage and failure characteristics at a more comprehensive level. Differences in the fracture behavior were found between the thermally sprayed Cr2O3 and TiO2 coatings, and a concept of critical impact energy is presented here. The superior cohesion of the TiO2 coating inhibited interlamellar cracking while the Cr2O3 coating suffered greater damage at high impact energies. The HVPI experiment has proven to be able to produce valuable information about the deformation behavior of coatings under high strain rates and could be utilized further in the development of wear-resistant coatings.

A two-step masterbatch mixing technique was studied for preparation of carbon nanotube-filled ethylene–propylene diene elastomer compounds, and compared to conventional one-step mixing process. In the two-step process, a masterbatch compound with carbon nanotube content of 50 parts per hundred was prepared by melt-mixing ethylene–propylene diene elastomer. This material was then compounded with pristine ethylene–propylene diene elastomer and composites with different carbon nanotube concentrations were compared. The aim of this study is to compare the efficiency of two different mixing processes on the dispersion of carbon nanotubes and to facilitate the handling of carbon nanotubes, as the masterbatch can be prepared in a controlled way and used for further dilution without the problems related to carbon nanotube processing. The compound properties were studied with emphasis on mechanical characterization and dynamic mechanical thermal analysis. Masterbatch mixing resulted in the similar mechanical properties of the composites compared to the direct mixing method. At the relatively low loadings of carbon nanotubes, the considerable improvements of the mechanical properties were observed. The aspect ratio of the carbon nanotubes determined by transmission electron microscope was found to be similar to the one calculated from the Guth equation. It showed a considerable reduction in aspect ratio independent of the used mixing method. acceptedVersion

Carbide free bainitic (CFB) steels have been tested in two heat treated conditions and compared with currently used quenched and tempered (QT) steel in an industrial mining application subjected to erosive-abrasive wear. A conventional sliding abrasion and a new application oriented high-stress erosion wear tests were performed in laboratory. The results of the erosion and the field tests were compared. The microstructural changes were investigated by optical and scanning electron microscopy. The hardness and hardness profiles of the steels were measured. The results showed that in the laboratory tests, the abrasion and erosion wear rates of the CFB steels were 35 and 45 % lower respectively in comparison to the QT steel. In the field test, the mass losses of the CFB steels were about 80 % lower in comparison with the QT steel. The improved wear resistance of the CFB steel can be explained by its higher hardness and higher work hardening. The erosion wear test was able to simulate the work hardening effect and the wear mechanisms observed in the field test samples. acceptedVersion submittedVersion

Three commercially available quenched wear resistant steel grades were compared with a structural steel and four elastomer materials to reveal the differences in their behavior in slurry erosion conditions and to find the best solutions for demanding applications. A slurry-pot tester, allowing simulation of various wear conditions with different minerals, particle sizes (up to 10 mm), abrasive concentrations, and sample angles were used to simulate different industrial slurry applications. In this study, granite and quartz with concentrations of 9 and 33 wt% were used as abrasives in tests conducted at 45° and 90° sample angles. The performance of the studied steels was evaluated with respect to their material properties such as hardness and microstructure. Furthermore, the cross-sections and wear surfaces of the test samples were analyzed to reveal the possible differences in the mechanical behavior of the materials during slurry erosion. The wear surface analyses show that abrasion is the dominating wear mechanism already for the smallest particle size of 0.1/0.6 mm. In low-stress abrasive slurry erosion with the smallest particles, the elastomers showed better wear resistance than the steels, whereas in demanding high-stress abrasive slurry erosion conditions the quenched wear resistant steels can well compete with elastomers in wear resistance. The relative wear performance of the steels increased with increasing abrasive size, while for the elastomers it decreased. acceptedVersion

A phase fluorimetric sensor targeted for the monitoring of dissolved oxygen concentration in microfluidic in vitro cell models is presented. The sensing surface of the sensor consists of oxygen sensitive fluorescent dyes (PtOEPK) embedded in a thin polystyrene film. The simulated fluorescence emission characteristics show highly anisotropic distribution, and an efficient optical read-out based on a parabolic lens is presented. Experimental results show that the applied sensing scheme allows one to use thin films (

Modeling and simulation for additive manufacturing (AM) is commonly used in industry. Nevertheless, a central issue remaining is the integration of different models focusing on different objectives and targeting different levels of details. The objective of this work is to increase the prediction capability of characteristics and performances of additively manufactured parts and to co-design parts and processes. The paper contributes to this field of research by integrating part's performance model and additive technology process model into a single early integrated model. The paper uses the dimensional analysis conceptual modeling (DACM) framework in an AM perspective to generate causal graphs integrating the AM equipment and the part to be printed. DACM offers the possibility of integrating existing knowledge in the model. The framework supported by a computer tool produces a set of governing equations representing the relationships among the influencing variables of the integrated model. The systematic identification of the weaknesses and contradictions in the system and qualitative simulation of the system are some of the potential uses of the model. Ultimately, it is a way to create better designs of machines and parts, to control and qualify the manufacturing process, and to control three-dimensional (3D) printing processes. The DACM framework is tested on two cases of a 3D printer using the fused filament fabrication (FFF) powder bed fusion. The analysis, applied to the global system formed of the 3D printer and the part, illustrates the existence of contradictions. The analysis supports the early redesign of both parts and AM process (equipment) and later optimization of the control parameters.

The continuous demand for higher power density leads to a very challenging operational environment for sliding bearings regarding pressures and deformations. Understanding of the deformation behavior of heavily loaded bearings becomes even more pronounced when modern hybrid multilayer designs are considered. The aim of this study is to develop a numerical, multi-physical model for the evaluation of journal bearing performance. Hydrodynamics were based on the Reynolds equation and deformations were calculated using the integrated finite element method. Elastic and thermal deformations have a significant effect on bearing performance and those deformations can be adjusted with properties of polymer layer. The design of hybrid bearings is delicate and their properties must be tailored according to the operating conditions. acceptedVersion

Heavy steel plates are used in demanding applications that require both high strength and hardness. An important step in the production of such components is cutting the plates with a cost-effective thermal cutting method such as flame cutting. Flame cutting is performed with a controlled flame and oxygen jet, which burns the steel and forms a cutting edge. However, the thermal cutting of heavy steel plates causes several problems. A heat-affected zone (HAZ) is generated at the cut edge due to the steep temperature gradient. Consequently, volume changes, hardness variations, and microstructural changes occur in the HAZ. In addition, residual stresses are formed at the cut edge during the process. In the worst case, unsuitable flame cutting practices generate cracks at the cut edge. The flame cutting of thick steel plate was modeled using the commercial finite element software ABAQUS. The results of modeling were verified by X-ray diffraction-based residual stress measurements and microstructural analysis. The model provides several outcomes, such as obtaining more information related to the formation of residual stresses and the temperature history during the flame cutting process. In addition, an extensive series of flame cut samples was designed with the assistance of the model. acceptedVersion

Thermally sprayed tungsten carbide (WC) and chromium carbide (Cr3C2) based hard metal coatings are commonly applied on component surfaces as corrosion and wear resistant layers. Typically, WC-Co/Ni with optional Cr addition and Cr3C2-25NiCr powders are sprayed with high velocity oxy-fuel (HVOF) or high velocity air-fuel (HVAF) processes. Due to the poor oxidation resistance of the WC particles, Cr3C2-25NiCr composition is typically selected for high temperature environments, up to 800-900°C. In this study, two distinct Cr3C2-based compositions of Cr3C2-50NiCrMoNb and Cr3C2-37WC-18NiCoCr were selected as interesting alternatives to conventional Cr3C2-25NiCr. Sliding wear behavior of the coatings sprayed with HVOF and HVAF processes were tested with a ball-on-disk configuration against an Al2O3 ball at room temperature and at 700°C. It was found that both alternative materials had comparable coefficients of friction with the Cr3C2-25NiCr coatings. The Cr3C2-37WC-18NiCoCr coatings provided improved wear resistance at room temperature conditions, but at 700°C the wear rate was increased to the level of the Cr3C2-50NiCrMoNb coatings. Cr3C2-25NiCr coatings experienced the lowest wear rates at elevated temperatures, which was even lower than at room temperature. acceptedVersion

Cavitation and cavitation erosion are sometimes unavoidable phenomena in hydro machine operation. For example, operating hydro turbines as regulating power leads to situations in which the risk of cavitation is accepted to some extent. Cavitation-resistant materials are therefore required to reduce machine damage and maintenance. This study characterizes the microstructure of two martensitic stainless steels from Francis turbines. They were already studied for cavitation erosion resistance in a previous study, and this study reveals the reasons behind the other steel having a significantly better resistance, while they had similar chemical compositions. The electron backscatter diffraction (EBSD) method is effective in defining the martensitic microstructure, specifically the block, packet, and prior austenite grain level. In addition, the retained austenite is effectively detected with the method. A fine prior austenite grain size and small packet and block sizes were found to be among the defining factors in cavitation erosion resistance of these steels. In addition, the transformation of retained austenite to martensite was detected in the edge region where cavitation had taken place. This transformation further increases cavitation erosion resistance. The better resistance of Steel 1 against cavitation was attributed to these microstructural differences. According to these findings, the microstructure in Steel 1 would be highly beneficial in building cavitation erosion resistant hydro machines and would be of interest to manufacturers of martensitic stainless steel components. acceptedVersion

Capacitive sensors can be used to monitor changes in materials by monitoring complex permittivity. Inductively coupled passive resonance sensors provide means to make short range wireless permittivity measurements if the sensors are embedded in the tested material. In this study, inductively coupled sensors were embedded in biodegradable polymers, which are important materials in regenerative medicine. However, it is challenging to observe their decay especially in vivo. After preparing the samples by compression moulding, the encapsulated sensors and a reference series were immersed in buffer solution. The signals from the passive resonance sensors were measured for eight weeks. In addition, mechanical and chemical testing was periodically carried out to monitor the state of the reference series. The wirelessly measured signals are compared with water absorption, flexural modulus, glass transition temperature and viscosity. publishedVersion

Zinc oxide (ZnO) is an important semiconductive material due to its potential applications, such as conductive gas sensors, transparent conductive electrodes, solar cells, and photocatalysts. Photocatalytic activity can be exploited in the decomposition of hazardous pollutants from environment. In this study, we produced zinc oxide thin films on stainless steel plates by hydrothermal method varying the precursor concentration (from 0.029 M to 0.16 M) and the synthesis temperature (from 70 °C to 90 °C). Morphology of the synthesized films was examined using field-emission scanning electron microscopy (FESEM) and photocatalytic activity of the films was characterized using methylene blue decomposition tests. It was found that the morphology of the nanostructures was strongly affected by the precursor concentration and the temperature of the synthesis. At lower concentrations zinc oxide grew as thin needlelike nanorods of uniform length and shape and aligned perpendicular to the stainless steel substrate surface. At higher concentrations the shape of the rods transformed towards hexagon shaped units and further on towards flaky platelets. Temperature changes caused variations in the coating thickness and the orientation of the crystal units. It was also observed, that the photocatalytic activity of the prepared films was clearly dependent on the morphology of the surfaces. publishedVersion

This paper presents an improved experimental setup for high strain rate testing based on the modified Tensile Hopkinson Split Bar device developed previously at TUT. The test setup can be used to study the effects of a sudden large change in the strain rate on the stress flow of the material. The setup allows deforming the sample at a low rate and at isothermal conditions before the high rate loading. During the strain rate jump, the deformation rate is rapidly increased by approximately six orders of magnitude. In this work, the low and high rate deformation of the specimen was recorded with a combination of low and high-speed digital cameras and analyzed using the Digital Image Correlation technique. The measurement provides information about the effects of the strain rate jump on the macroscopic response of the material and allows accurate observation of the deformation of the sample just before, during, and immediately after the strain rate jump, when the conditions change from isothermal to adiabatic. In this paper, we present the results for a metastable austenitic stainless steel and discuss the effects of the strain rate jump on the strain-hardening rate, compare the experimental results with numerical results from a thermomechanical model, and evaluate the effects of the preceding deformation at a low strain rate on the strain localization. We conclude that the strain rate jump results in a clear decrease in the strain-hardening rate, the deformation following the jump is uniform along the gauge section, and that the strain localization is not significantly affected by the strain rate or the amount of pre-strain in the studied conditions.

Rheology and FTIR spectroscopy are compared as methods to study the degree of photodegradation in polypropylene (PP) and polystyrene (PS) sheets. The materials are hot pressed, artificially photo-aged with fluorescent lights for 4–2048 h and then measured with a rotational rheometer and FTIR. Both materials show a tendency for chain scission which can be seen as a reduction in viscosity. Changes in PP can be observed with both methods after 256 h of irradiation. Changes in PS become significant in rheology after 64 h but in FTIR only after 1024 h of irradiation. Due to the different chemical nature of the materials, the degradation of PS is rather linear with exposure, whereas the degradation of PP is more exponential. Using the zero shear viscosities obtained through extrapolations of the Cole–Cole and Carreau–Yasuda models, relative molecular weights are estimated with the aid of the power–law relationship between these two. These results are compared with the carbonyl indices determined from the FTIR spectra. Rheology is found to be a viable alternative for FTIR in certain situations. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42246.

Slippery, liquid-infused porous surfaces offer a promising route for producing omniphobic and anti-icing surfaces. Typically, these surfaces are made as a coating with expensive and time consuming assembly methods or with fluorinated films and oils. We report on a route for producing liquid-infused surfaces, which utilizes a liquid precursor fed oxygen-hydrogen flame to produce titania nanoparticles deposited directly on a low-density polyethylene film. This porous nanocoating, with thickness of several hundreds of nanometers, is then filled with silicone oil. The produced surfaces are shown to exhibit excellent anti-icing properties, with an ice adhesion strength of ∼12 kPa, which is an order of magnitude improvement when compared to the plain polyethylene film. The surface was also capable of maintaining this property even after cyclic icing testing. Slippery, liquid-infused porous surfaces (SLIPSs) are nature inspired surfaces that are designed to repel liquid and solid materials. These surfaces have been shown to pose anti-icing properties, which broadens the available end-uses from the chemical industry to arctic transportation and energy production. The method behind repellency of SLIPSs relies on preventing outside liquids from penetrating the surface structure to the Wenzel state. Instead, the slippery liquid within the porous solid supports the Cassie-Baxter state (instead of air, here the porous structure is filled with lubricant), where the reduced area of the porous solid surface is available to interact with the liquid or ice to be repelled. The difference between Wenzel and Cassie-Baxter states is illustrated in Figure 1. This phenomenon is exploited in many superhydrophobic surfaces where an air cushion is entrapped within the porous solid surface. As a result, spherical water drops easily roll off the surface (and have static contact angles larger than 150°). publishedVersion

Fins and fin arrays with constant temperature at the fin base have known solutions for natural convection. However, in practical applications, no simple solution exists for maximum temperature of heat sink with many heat dissipating components located at the base plate. A calculation model is introduced here to solve this practical problem without time consuming CFD modelling of fluid flow and heat transfer. Solutions with the new model are compared with some simple analytical and CFD solutions to prove that the results are accurate enough for practical applications. Seminal here is that results are obtained many orders of magnitude faster than with CFD. This much shorter calculation time scale makes the model well suited for multi-objective optimization in, e.g., simultaneous minimization of heat sink maximum temperature, size, and mass. An optimization case is presented in which heat sink mass and size are significantly reduced over those of the original reference heat sink. publishedVersion

This paper aims to introduce small angle X-ray scattering (SAXS) as a promising technique for measuring size and size distribution of TiO2 nanoparticles. In this manuscript, pulsed laser ablation in liquids (PLAL) has been demonstrated as a quick and simple technique for synthesizing TiO2 nanoparticles directly into deionized water as a suspension from titanium targets. Spherical TiO2 nanoparticles with diameters in the range 4–35 nm were observed with transmission electron microscopy (TEM). X-ray diffraction (XRD) showed highly crystalline nanoparticles that comprised of two main photoactive phases of TiO2: anatase and rutile. However, presence of minor amounts of brookite was also reported. The traditional methods for nanoparticle size and size distribution analysis such as electron microscopy-based methods are time-consuming. In this study, we have proposed and validated SAXS as a promising method for characterization of laser-ablated TiO2 nanoparticles for their size and size distribution by comparing SAXS- and TEM-measured nanoparticle size and size distribution. SAXS- and TEM-measured size distributions closely followed each other for each sample, and size distributions in both showed maxima at the same nanoparticle size. The SAXS-measured nanoparticle diameters were slightly larger than the respective diameters measured by TEM. This was because SAXS measures an agglomerate consisting of several particles as one big particle which slightly increased the mean diameter. TEM- and SAXS-measured mean diameters when plotted together showed similar trend in the variation in the size as the laser power was changed which along with extremely similar size distributions for TEM and SAXS validated the application of SAXS for size distribution measurement of the synthesized TiO2 nanoparticles. publishedVersion

The in-service cutting edge of a mining loader bucket was investigated and its wear behavior compared with samples tested in the laboratory to assess how well the wear testing methods correlate with the in-service conditions. The examined in-service cutting edge of a bucket had been run in an underground mine with quarry gravel and it was made of wear resistant steel. The wear behavior of the cutting edge was simulated in the laboratory scale with several application oriented abrasive and impact-abrasive wear testing methods. In addition to the contact mode, high loads, large abrasive size, abrasive type, and the comminution of the abrasive formed the basis for the design of the laboratory experiments. The wear surfaces and cross-sections of the original cutting edge and the test samples were characterized, and the wear behaviors were compared with each other. Work hardening of the steels occurred in all cases, but the amount of plastic deformation and the depth of the wear scars varied. submittedVersion acceptedVersion