Load Support Research Articles

Synthesis and Characterization of Zwitterionic Polymer Brush Functionalized Hydrogels with Ionic Responsive Coefficient of Friction.

Freeze-thaw poly(vinyl alcohol) hydrogels (PVA-H) offer great potential for several biomedical applications due to their biomimetic mechanical properties and biocompatibility. Despite these advantages, the use of PVA-H for load bearing applications has been limited due to poor performance in boundary lubrication compared to natural tissue such as articular cartilage. Recently, zwitterionic polymer brushes have been shown to act as effective boundary lubricants on rigid substrates; however, to the best of our knowledge, the synergistic effects of zwitterionic brushes coupled with the biomimetic fluid load support exhibited by hydrogels have not been reported. We report here on our investigation involving the synthesis and characterization of two unique types of polymer brush functionalized PVA hydrogels. The zwitterionic polymers that were compared contained either [2-(methacryloyloxy)ethyl]dimethyl-3-sulfopropylammonium hydroxide, PMEDSAH, or 2-methacryloyloxyethylphosphorylcholine, PMPC, repeating units. Both hydrogels coated with zwitterionic polymers were found to be cytocompatible. We report further on micrometer-scale surface properties via water contact angle goniometry, surface roughness measurements, and scanning electron microscopy. Finally, the impact of brush functionalization on the mechanics of the tribologically enhanced gels is reported with comparison to natural articular cartilage within the context of Hertzian contact theory.

Cartilage Biomechanical Response Differs Under Physiological Biaxial Loads and Uniaxial Cyclic Compression.

The main function of articular cartilage is to distribute loads and provide low friction for the opposing surfaces in synovial joints. Biphasic lubrication provided by high fluid load support due to relative motion of the contact surfaces has been widely accepted as the main lubrication mode in diarthrodial joints. However, assessment of chondrocyte response to mechanical loads typically employed nonphysiological uniaxial loads with static contact area. This study aimed to introduce a more physiologically relevant loading protocol for in vitro mechanobiological testing of cartilage explants. Finite element analysis was conducted to examine the biomechanical response of cartilage to two different loading regimes, biaxial loading, that permits migrating contact area, and unconfined uniaxial cyclic compression, traditionally used in mechanobiological experiments. Results predicted in this study showed that continuous tissue rehydration provided by relative surface motion maintained constant fluid pressure and tissue strains through the simulation. On the contrary, due to rapid tissue consolidation predicted in cyclic compression simulation, fluid pressure and transverse strain were reduced by 19% and 26%, respectively. Furthermore, relative surface motion simulation resulted in depth-dependent distribution of fluid pressure and tissue strains while unconfined uniaxial cyclic compression produced nearly uniform fluid pressure through the depth but higher at the center of the sample. Based on the results obtained from this study and since sliding contact occurs in vivo, this physiological loading mode should be considered in assessing biomechanical and mechanobiological cartilage behavior.

Mechanics and tribology of a zwitterionic polymer blend: Impact of molecular weight.

Despite decades of biomimetic materials development, the tribological properties of articular cartilage remain unrivalled. This manuscript presents the design and material properties of a polymer blend composed of poly (vinyl alcohol) (PVA) and a zwitterionic polysulfobetaine (PMEDSAH) prepared into hydrogel form using a cyclic freeze-thaw method. The PVA hydrogel matrix provides mechanical strength while the zwitterionic polymer, PMEDSAH, is intended to act as a boundary lubricant. The formation of PVA-PMEDAH hydrogel blends was found to result in unique biomimetic system where the boundary lubricant elutes from the bulk material to the surface in response to applied pressure. This behavior is attributed to the high-water content of the PVA hydrogel matrix and the solubility of PMEDSAH in aqueous solution. In addition to characterizing the effects of boundary lubricant molecular weight on the diffusive properties of the hydrogel blend, we report the coefficient of friction, μ, versus sliding speed for the hydrogel/glass interface. Consistent with our prior findings, PMEDSAH was found to engender lubricious behavior and the dependence of μ on sliding velocity indicated a repulsive interaction with glass rather than an attractive one. This result agrees with the hydration lubrication hypothesis. Contact mechanics analyzed within the context of Hertzian biphasic theory were also investigated, revealing that the introduction of PMEDSAH enhances the hydrogel's ability to provide interstitial fluid load support.

Detrimental effects of long sedentary bouts on the biomechanical response of cartilage to sliding

ABSTRACTPurpose/Aim: Epidemiological evidence suggests, contrary to popular mythos, that increased exercise/joint activity does not place articular cartilage at increased risk of disease, but instead promotes joint health. One explanation for this might be activity-induced cartilage rehydration; where joint articulation drives restoration of tissue hydration, thickness, and dependent tribomechanical outcomes (e.g., load support, stiffness, and lubricity) lost to joint loading. However, there have been no studies investigating how patterning of intermittent articulation influences the hydration and biomechanical functions of cartilage.Materials and Methods: Here we leveraged the convergent stationary contact area (cSCA) testing configuration and its unique ability to drive tribological rehydration, to elucidate how intermittency of activity affects the biomechanical functions of bovine stifle cartilage under well-controlled sliding conditions that have been designed to model a typical “day” of human joint activity.Results: For a fixed volume of “daily” activity (30 min) and sedentary time (60 min), breaking up intermittent activity into longer and less-frequent bouts (corresponding to longer continuous sedentary periods) resulted in the exposure of articular cartilage to markedly greater strains, losses of interstitial pressure, and friction coefficients.Conclusions: These results demonstrated that the regularity of ex vivo activity regimens, specifically the duration of sedentary bouts, had a dominant effect on the biomechanical functions of articular cartilage. In more practical terms, the results suggest that brief but regular movement patterns (e.g., every hour) may be biomechanically preferred to long and infrequent movement patterns (e.g., a long walk after a sedentary day) when controlling for daily activity volume (e.g., 30 min).

Effect of demand response program of loads in cost optimization of microgrid considering uncertain parameters in PV/WT, market price and load demand

Using renewable distributed generators as photovoltaic cell and wind turbine in microgrid includes green and free energy exploitation. However, uncertainty of generated energy from these resources may underestimate energy planning for load demands. The uncertainty may be from market price and load demand in addition to the renewable distributed generators. To overcome the uncertainty challenge, energy storage system and demand response program with cooperation of users on demand side are applied as solutions to plan the energy flow in microgrid to guarantee the voltage stability and essential load supporting. In this paper, price-based demand response for industrial, commercial and house loads are considered in which the effect of demand response on the cost reduction is analyzed and discussed. Electrical and heat demand are considered in the microgrid while uncertainty of renewable distributed generators, market price and load demand are modeled and estimated by point estimation method. Simulation results with three scenarios are performed with and without price-based demand response program and results are compared. As shown in simulation results, demand response has highly reduced total cost (22–28% related to the case without that) where voltage dip (maximum 1.5%) and power deviation (maximum 1.33%) are also improved in the microgird.

Assessment of the stresses produced on the bone implant/tissue interface to the different insertion angulations of the implant - a three-dimensional analysis by the finite elements method.

BackgroundThe present study aimed to assess the stresses produced on the surface of the bone tissue around dental implants with three different insertion angulations subjected to axial and oblique loading. Material and MethodsThe study was created according to the recommendations of the Checklist for Reporting In-vitro Studies (CRIS). The Straumann™ bone level RC (4.1 x 10 mm) implant, Cone Morse connection (CM), RC Straumann Variobase™ with abutment (3.5 mm) was placed in the region of element 16, with the platform positioned at the height of the bone crest. Three assessment models were produced: model M1 or control - implant perpendicular to the bone crest; model M2 - implant angulated at 17° relative to the bone crest; and model M3 - implant angulated at 30° relative to the bone crest. The masticatory loads were simulated with 100 N of intensity and two loading patterns (axial and oblique) were applied to each model. Then, the models were exported to the finite elements simulation software Ansys Workbench V19.2 (Ansys Inc., Canonsburg, PA, USA). To assess the finite elements, qualitative and quantitative analyses were performed. ResultsIt was observed that, under axial loading, qualitatively, the peaks occurred in the cavosurface region, palatal aspect in M1 and M2, and buccal aspect in M3. Quantitatively, the greatest angulation resulted in a low stress peak. Under oblique loading, qualitatively, the peaks occurred in the cavosurface region, buccal aspect in the three groups. Quantitatively, the greatest angulation of the implant resulted in an increase in stress peaks on the buccal aspect. ConclusionsUnder axial loading, the three insertion angulations of the implant - M1, M2, and M3 - were clinically viable. When subjected to oblique loading, the 30° angulation (M3) suggested a significant risk of bone loss and it was contraindicated. Key words:Finite element analysis, dental implants, load support.

Analysis of residential building with STAAD. Pro & ETABS

A building that overlooks multiple floors is a multi-story structure. The multi-story buildings are designed to increase the building's floor area without raising the land area and saving money. In these modern days the Buildings are made to fulfill our basic aspects and better Serviceability. It is not an issue to construct a building any how its, important to construct an efficient building which will serve for many years without showing any failure. In this paper aims to finding better analysis for creating load case, applying load combinations, support reactions & reinforcement of column and beam etc. Then reviewing (whether beam or column passed in the loads or failed). This complete design analysis is the case study of ongoing building project in Hyderabad and standard code books (IS 456: 2000, SP 16) are used for the building analysis.

Принцип «позитивної суми» у дорожній сфері: децентралізація доріг

The article is aimed at disclosing the issue of financial support for the construction, reconstruction, repair and maintenance of motor roads in the context of implementation of budget decentralization and decentralization of road management. The article specifies the steps taken towards implementation of decentralization in the sphere of road infrastructure of Ukraine and the introduction of budget decentralization: distribution of functions and powers in the road sphere at the subregional level of management and the updated mechanism of financing the road industry. Both the dynamics of formation and distribution of the State Road Fund and the status of distribution of subvention on the streets and roads of settlements are analyzed. The vision of the main risks of financial support for the maintenance of streets and roads of communal property in settlements in 2021 is disclosed. The directions of improvement of the system of financial support for the construction, reconstruction, repair and maintenance of motor roads are proposed, including in particular: the need to deepen diversification of sources of formation of the State Road Fund; consolidation of the proper guaranteed part of the State Road Fund’s costs for the maintenance of streets and roads of communal property in settlements; balancing the expenditure load and financial support for the implementation of road projects; increasing the level of transparency of decision-making in the distribution of financial resources intended for the construction, reconstruction, major, ongoing repair of motor roads.

Power System Improvement of Different Coordinated Electric Vehicles Integration Approaches with Superconducting Magnetic Energy Storage

Nowadays, electric vehicles have a considerable effect on the electrical system, thus their analysis based on different electric vehicle integration approaches is necessary. This paper exhibits four case studies for electric vehicles with the grid to exhibit their influence on the electrical network and reduce power loss and voltage fluctuation. Furthermore, the growing load demand matters, management and support of active and reactive power, and load balancing are discussed. Fuzzy logic control is applied to estimate the process of the charging/discharging. Moreover, a controlled superconducting magnetic energy storage system is utilized for the power grid which integrates with electric vehicles to the level of load demand during on-peak load and fast charging. A coordinated control between electric vehicles and superconducting magnetic energy storage unit is applied to level the power required by electric vehicles and improve the power system performance. Electricity price is a common coordination signal for both electric vehicles and superconducting magnetic energy storage, which depends on fuzzy control. The simulation results implemented by the Matlab Simulink tool show the effectiveness of the coordination control technique and superconducting magnetic energy storage in minimizing power loss and voltage fluctuation. Besides that, it helps to alleviate the active power and reduce the reactive power provided by the grid.

Optimization of Cost and Time of Repair and Rounding of Roads With Way Pavement Design Manual Method 2013

Smoothness, safety, and comfort of traffic depend on road pavement conditions. If the width of the road is narrow, damaged, hollow, the traffic will disrupted; the travel time will increase, fuel consumption increases, the risk of damage to high vehicles and so on, if there is no immediate improvement in the form of an increase, the damage will increase. To deal with this problem, it is necessary to research and plan road improvements with widening, an increase in existing pavements with overlays, the need for cost and time of implementation. The Mojokerto - Ploso road segment is an alternative route connecting the cities of Mojokerto - Jombang, and Lamongan. Based on the status of the road is the provincial road, and based on the function is the Collector’s road. Furthermore, for the planning of improvement and widening required subgrade CBR data, for overlay planning, a Test Pit data is needed to determine the existing pavement structure and traffic data. In determining the road widening plan, the 2015 revised Road Pavement Design Manual (MDP) method for overlaying was used with the Planning Guidelines for Pt-T-01-2002-B Bending Pavement Thickness and calculating the Budget using Work Unit Price Analysis (AHSP ) 2013, creating a Schedule of Work (Time Schedule), as well as calculating the critical path to find out the critical path in carrying out the work. To planning data analysis is needed - traffic data, land investigation, layer thickness calculation on widening, overlay layer thickness, cost requirements, execution time and critical track path. From the calculation results, the road widening obtained AC = 5 cm pavement arrangement, ATB = 14 cm, CTB = 30 cm, Class B Aggregate = 20 cm, the optional load support layer = 85 cm, using geogrid as the selected urine separator with subgrade, in the old pavement repair (overlay) with an overlay, the AC = 5 cm arrangement, ATB = 14 cm, at a cost of Rp. 19,200,000,000.00 (Nineteen billion two hundred million rupiahs) with a 20-year plan life, as well as a 6-month implementation time.

Laboratory investigation of the mechanical properties of coal-rock combined body

Understanding the behavior of the top-coal caving mining face and immediate roof can be used to enhance buffering effects. The mechanical properties of the coal-rock combined body (CRCB) play a vital role in the performance of overburden load transmittance and support resistance design. We define and derive the relative physical and mechanical parameters of CRCB to illustrate and analyze the influence of coal-rock height ratio (CRHR), coal and rock mass behavior, and interface parameters on CRCB mechanical properties. We conducted uniaxial compression tests to obtain uniaxial compressive strength (UCS), elastic modulus (EM), and the full range of stress–strain curves. Our results show that UCS is positively correlated with EM. However, CRCB EM and UCS decrease with increasing CRHR or effective coal-rock height ratio (ECRHR) and the slope of the curves gradually decreases. CRCB mechanical parameters increase linearly with EM of the coal or rock mass. Although increased coal-rock interface angles (IA) lead to increased CRCB mechanical parameters, the incremental value can be ignored. Sensitive analysis shows that the rank of influential factors on CRCB properties is CRHR/ECRHR > coal strength > rock strength > IA.

Coordinated Multilayer Control for Energy Management of Grid-Connected AC Microgrids

This paper proposes a coordinated multilayer control strategy for the energy management (EM) of grid-connected ac microgrids. The strategy predicts the customer's load demand and the photovoltaics (PV) power generation for a day-ahead EM. It utilizes the PV power generations and the bidirectional energy transactions from electric vehicles and battery storage to provide a combined response for load support. The system also predicts any uncertainties in customers demand and power generations and implements day-ahead precautionary measures to tackle that uncertainty. Two different prediction strategies are used, autoregressive moving average and artificial neural networks, and their performances for a day-ahead EM are investigated. The reference power from the tertiary layer EM is sent to the local controllers for power regulation at the inverter level. Additionally, the varying power output reference obtained from a day-ahead EM is classified into the slow, medium, and fast variations. The performance of the local controller employed in the interfacing grid-connected three-phase inverter is tested during the above-mentioned power reference variations. The total harmonic distortion incorporating a moving window technique is calculated for the ac output current during each class of power variations over a day.

Multiphase Computational Fluid Dynamics Analysis of Hydrodynamic Journal Bearing Under the Combined Influence of Texture and Slip

The drive to maintain the environmental sustainability and save the global energy consumption is urgent, making every powertrain system component a candidate to enhance efficiency. In this work, the combined effects of the slip boundary and textured surface in hydrodynamic journal bearing as one of the critical components in industrial powertrain and engine systems are assessed using a multiphase computational fluid dynamic analysis that allows for phase change in a cavitation process and arbitrary textured geometry. The texture studied consists of regularly spaced rectangular dimples through two-dimensional (infinitely long) journal bearing. The modified Navier–slip model is employed to describe the slip boundary condition. A systematic comparison is made for various textured configurations varying the texture depth and the length of the texturing zone with respect to the performance of a smooth (untextured) bearing for several eccentricity ratios. The effectiveness of the texture with or without slip at enhancing the load support over a corresponding smooth bearing is investigated with the parameters. The detrimental or beneficial effect of surface texturing as well as the slip promotion is explained in terms of the mechanisms of pressure generation for several eccentricity ratios. The results of the present work indicate that journal bearing textured by a proper texturing zone and dimple depth are characterized by substantial load support levels. However, in the range of high eccentricity ratios, the promotion of texturing and slip can significantly degrade the performance of the load support.

Circular space curve frame (3D) with any load and spring supports by Transfer Matrix Method and Finite Element Method

In this paper, authors present a new numerical method, combining the Transfer Matrix Method and Finite Element Method (TMM - FEM), to analyze spatially circular curved bar, with general load and elastic support. Analysis space curved bar is complex problem because conventional methods will not simultaneously calculate the entire structure, or difficulty in establish the stiffness matrix, or the size of stiffness matrix is too large due to multiple elements. TMM - FEM method is proposed to promote the advantages of each method. Due to being directly generated from the parametric equations of the bar axis, the analytical results are accurate. Results are programed in Matlab and verified with SAP2000 programe.

Influence of micro-groove attributes on frictional power loss and load-carrying capacity of hybrid thrust bearing

PurposeMicro-surface texturing is emerging as a possible way to enhance the tribological performance of hydrodynamic fluid film bearings. In view of this, numerical simulations are carried out to examine the influence of surface texture on performance of hybrid thrust bearing system. This paper aims to determine optimum attributes of micro-grooves for thrust bearing operating in hybrid mode.Design/methodology/approachAn iterative source code based on finite element formulation of Reynolds equation has been developed to numerically simulate flow of lubricant through the bearing. Mass-conserving algorithm based on Jakobsson–Floberg–Olsson (JFO) condition has been used to numerically capture cavitation phenomenon in the bearing. Gauss Siedel method has been used to obtain steady state performance parameters of the bearings.FindingsA parametric study has been performed to improve the load supporting capacity of the bearing by optimizing micro-groove attributes and configuration. It is noticed that use of full-section micro-groove is beneficial in improving the efficiency of bearing by enhancing the fluid film reaction and reducing the film frictional power losses.Originality/valueThis study is helpful in examining the usefulness of micro-groove textured surfaces in hybrid thrust bearing applications.

Control of Dissipation Sources: A Central Aspect for Enhancing the Mechanical and Mechanobiological Performances of Hydrogels.

Development of mechanically durable and biologically inductive hydrogels is a major challenge for load-bearing applications such as engineered cartilage. Dissipative capacity of articular cartilage is central to its functional behavior when submitted to loading. While fluid frictional drag is playing a significant role in this phenomenon, the flow-dependent source of dissipation is mostly overlooked in the design of hydrogel scaffolds. Herein, we propose an original strategy based on the combination of fluidic and polymeric dissipation sources to simultaneously enhance hydrogel mechanical and mechanobiological performances. The nondestructive dissipation processes were carefully designed by hybrid cross-linking of the hydrogel network and low permeability of the porous structure. It was found that intrachain and pore water distribution in the porous hydrogels improves the mechanical properties in high water fractions. In contrast to widely reported tough hydrogels presenting limited load support capability at low strain values, we obtained stiff and dissipative hydrogels with unique fatigue behavior. We showed that the fatigue resistance capability is not a function of morphology, dissipation level, and stiffness of the viscoelastic hydrogels but rather depends on the origin of the dissipation. Moreover, the preserved dissipation source under mechanical stimulation maintained a mechanoinductive niche for enhancing chondrogenesis owing to fluid frictional drag contribution. The proposed strategy can be widely used to design functional scaffolds in high loading demands for enduring physiological stimuli and generating regulatory cues to cells.

Hydrodynamic Lubrication of Textured Journal Bearing Considering Slippage: Two-dimensional CFD Analysis Using Multiphase Cavitation Model

Partial texturing of the surface of journal bearings have been proven very beneficial in terms of friction coefficient. In the present work, the load support of the hydrodynamic textured journal bearing combined with artificial slippage is fully characterized by means of computational fluid dynamics (CFD) simulations based on the numerical solution of the Navier–Stokes equations for incompressible flow. In order to model slippage, the enhanced user-defined-function (UDF) code is developed. Realistic boundary condition is employed by implementing the mixture multiphase model to model a cavitation in the bearing. The numerical analysis is performed under the condition of different groove depths, eccentricity ratios and slippage placements along the textured area of bearing. The simulation results including hydrodynamic pressure and load support are gained and compared for conventional smooth parameters. A reference to determine optimal groove depths as well as best artificial slippage placement of textured bearing under different conditions of loading are proposed. Based on the present results, favorable slippagetextured journal bearing design can be assessed.

Effect of structural distortions on articular cartilage permeability under large deformations.

The permeability of articular cartilage has a key role in load support and lubrication in diarthrodial joints. The microstructural rearrangement and consequent alteration in permeability caused by the large deformations undergone by cartilage have been previously modelled with a multi-scale approach. At the microscopic scale, the tissue is regarded as a homogeneous fluid-filled proteoglycan matrix reinforced by collagen fibres. A material point is described by a representative element of volume (REV), comprising a collagen fibre surrounded by a jacket of fluid-saturated proteoglycan matrix. At the macroscopic scale, the statistical orientation of the fibres is accounted for via averaging of the REV over all possible directions. The previous models accounted for volumetric deformation and fibre reorientation, but did not consider the cross-sectional distortion of the REV, which changes the widths of the fluid channels in different directions. We account for REV cross-sectional distortion and demonstrate its effects by simulating confined compression tests for the superficial, middle and deep zones of articular cartilage. The proposed model captures published experimental results that were not reproduced correctly by the previous models, and shows that each factor (volumetric deformation, fibre reorientation, REV cross-sectional distortion) can be dominant, depending on fibre orientation and amount of compression, implying that all three factors should be accounted for when modelling cartilage permeability.

Effects of mechanical injury on the tribological rehydration and lubrication of articular cartilage

Healthy articular cartilage is crucial to joint function, as it provides the low friction and load bearing surface necessary for joint articulation. Nonetheless, joint injury places patients at increased risk of experiencing both accelerated cartilage degeneration and wear, and joint dysfunction due to post-traumatic osteoarthritis (PTOA). In this study, we used our ex vivo convergent stationary contact area (cSCA) explant testing configuration to demonstrate that high-speed sliding of healthy tissues against glass could drive consistent and reproducible recovery of compression-induced cartilage deformation, through the mechanism of ‘tribological rehydration’. In contrast, the presence of physical cartilage damage, mimicking those injuries known to precipitate PTOA, could compromise tribological rehydration and the sliding-driven recovery of cartilage function. Full-thickness cartilage injuries (i.e. fissures and chondral defects) markedly suppressed sliding-driven tribological rehydration. In contrast, impaction to cartilage, which caused surface associated damage, had little effect on the immediate tribomechanical response of explants to sliding (deformation/strain, tribological rehydration, and friction/lubricity). By leveraging the unique ability of the cSCA configuration to support tribological rehydration, this study permitted the first direct ex vivo investigation of injury-dependent strain and friction outcomes in cartilage under testing conditions that replicate and maintain physiologically-relevant levels of fluid load support and frictional outcomes under high sliding speeds (80 mm/s) and moderate compressive stresses (~0.3 MPa). Understanding how injury alters cartilage tribomechanics during sliding sheds light on mechanisms by which cartilage's long-term resilience and low frictional properties are maintained, and can guide studies investigating the functional consequences of physical injury and joint articulation on cartilage health, disease, and rehabilitation.

The effect of alloying elements on the properties of pressed and non-pressed biodegradable Fe–Mn–Ag powder metallurgy alloys

Current trends in the biodegradable scaffold industry call for powder metallurgy methods in which compression cannot be applied due to the nature of the scaffold template itself and the need to retain the shape of an underlying template throughout the fabrication process. Iron alloys have been shown to be good candidates for biomedical applications where load support is required. Fe–Mn alloys were researched extensively for this purpose. Current research shows that all metallurgical characterisation and corrosion test on Fe–Mn and Fe–Mn–Ag non pre-alloyed powder alloys are performed on alloys which are initially pressed into greens and subsequently sintered. In order to combine the cutting-edge field of biodegradable metallic alloys with scaffold production, metallurgical characterisation of pressed and non-pressed Fe, Fe–Mn and Fe–Mn–Ag sintered elemental powder compacts was carried out in this study. This was performed along with determination of the corrosion rate of the same alloys in in vitro mimicking solutions. These solutions were synthesised to mimic the osteo environment in which the final scaffolds are to be used.Both pressed and non-pressed alloys formed an austenite phase under the right sintering conditions. The corrosion rate of the non-pressed alloy was greater than that of its pressed counterpart. In a potentiodynamic testing scenario, addition of silver to the alloy formed a separate silver phase which galvanically increased the corrosion rate of the pressed alloy. This result wasn't replicated in the non-pressed alloys in which the corrosion rate was seen to remain similar to the non-silver-bearing alloy counterparts.