Erosion characteristics on surface texture of additively manufactured AlSi10Mg alloy in SiO2 quartz added slurry environment

Purpose The main purpose of this work is to explore the erosion wear characteristics of additively manufactured aluminium alloy. Additive manufacturing (AM), also known as three-dimensional (3D) manufacturing, is the process of manufacturing a part designed in a computer environment using different types of materials such as plastic, ceramic, metal or composite. Similar to other materials, aluminum alloys are also exposed to various wear types during operation. Production efficiency needs to be aware of its reactions to wearing mechanisms. Design/methodology/approach In this study, quartz sands (SiO2) assisted with oxide ceramics were used in the slurry erosion test setup and its abrasiveness on the AlSi10Mg aluminum alloy material produced by the 3D printer as selective laser melting (SLM) technology was investigated. Quartz was sieved with an average particle size of 302.5 µm, and a slurry environment containing 5, 10 and 15% quartz by weight was prepared. The experiments were carried out at the velocity of 1.88 (250 rpm), 3.76 (500 rpm) and 5.64 m/s (750 rpm) and the impact angles 15, 45 and 75°. Findings With these experimental studies, it has been determined that the abrasiveness of quartz sand prepared in certain particle sizes is directly related to the particle concentration and particle speed, and that the wear increases with the increase of the concentration and rotational speed. Also, the variation of weight loss and surface roughness of the alloy was investigated after different wear conditions. Surface roughness values at 750 rpm speed, 10% concentration and 75° impingement angle are 0.32 and 0.38 µm for 0 and 90° samples, respectively, with a difference of approximately 18%. Moreover, concerning a sample produced at 0°, the weight loss at 250 rpm at 10% concentration and 45° particle impact angle is 32.8 mg, while the weight loss at 500 rpm 44.4 mg, and weight loss at 750 rpm is 104 mg. Besides, the morphological structures of eroded surfaces were examined using the scanning electron microscope to understand the wear mechanisms. Originality/value The researchers verified that this specific coating condition increases the slurry wear resistance of the mentioned steel. There are many studies about slurry wear tests; however, there is no study in the literature about the quartz sand (SiO2) assisted slurry-erosive wear of AlSi10Mg alloy produced with AM by using SLM technology. This study is needed to fill this gap in the literature and to examine the erosive wear capability of this current material in different environments. The novelty of the study is the use of SiO2 quartz sands assisted by oxide ceramics in different concentrations for the slurry erosion test setup and the investigations on erosive wear resistance of AlSi10Mg alloy manufactured by AM.

Laboratory measurements of the erodibility of gravelly soils

The critical shear stress and erodibility of soil are fundamental parameters for modeling embankment breaching. Unfortunately, very few studies have examined the erosion characteristics of soils consisting predominantly of particles larger than sand. This report presents results of an experimental study in which the erosion characteristics of gravelly soils were measured. A flume apparatus was developed in which 0.45-m-square samples were extruded into confined flow. A mechanical laser system allowed the measurement of scour in real time, resulting in a continuous and automated erosion test. The critical shear stress of a uniform gravel was found to match the expected values based on the Shields diagram, while tests that were composed largely of gravel but contained other soils, such as sand, silt, and clay, varied significantly with the critical shear stress and erodibility, depending highly on the characteristics of the finer soils.

Experimental and Computational Investigation of Flow Fields using Accelerated Erosion Test Ring (AETR)

The erosion of the blades of hydraulic pumps and turbines, caused due to the water that has enormous suspended particles and erosive agents, is a severe global challenge among scientists and engineers. In the present work, an attempt has been made to compute the extent of erosion caused by water when it passes through devices like hydraulic machines, centrifugal pumps and turbines. Experimental and computational techniques using pitched turbine blades with 45o with the horizontal plane under down pumping condition is employed for investigation of the suspension phenomena for calculating erosion wear by sand suspended in water in river, canal on turbine, pump blades. An experimental set up, named as Accelerated Erosion Test Rig (AETR), is developed through dimensional analysis. For experimental analysis, the sand particle size and propeller dimensions were varied while running the propeller at different speeds. Experimental results revealed that the propeller speed must be maintained at an optimum value, preferably lower speeds, to ensure maximum lifting of impurities and sand particles from the base of the cylinder.

Correlation between experimental and analytic approaches to study the erosion rate of aluminum-metal matrix composites

The incorporation of a ceramic particles like SiC, Al2O3, and TiO2 into aluminum matrices results in Aluminum composite better mechanical and physical properties that make them attractive for various applications such as Aircraft, Helicopter, High-speed automobile, and Submarine. In this study, the erosion properties of the aluminum composite were studied in dry conditions using sand blast-erosion test rig. Impact velocity, standoff distance, particle size, particulate (wt. %), and impingement angle were preferred as control factors. Taguchi method, Grey relational and regression analysis were considered for optimizing the erosion process parameters. L27 orthogonal array was determined for the experimental trials. The most significant factors in the process were identified. Nonlinear regression model has been developed for Grey Relational Grade in relation to the different erosion parameters. An optimization schema is established based on a correlation between analytic and experimental results.

EFFECT OF MIG WELDING PROCESS PARAMETERS ON EROSION AND CORROSION BEHAVIOR OF ASTM A106 GRADE-B PIPE WELDMENTS

Evaluating the integrity of the welded pipes used for fluid transportation in processing industries demands certain investigations on the erosion and corrosion behavior under various environmental conditions. ASTM A106 Grade-B pipes are butt welded using an automated MIG welding setup to obtain the optimum output response such as Reinforcement Form Factor (W1), Penetration Shape Factor (W2), and Tensile Strength (W3) in the weldments. The slurry erosion test is conducted on the weldment surface by varying the velocity and erodent concentration in acidic (0.1M H2SO[Formula: see text] and alkaline (3.5%[Formula: see text]wt. NaCl) conditions. Correspondingly, the samples are subjected to electrochemical corrosion test in 0.1[Formula: see text]M H2SO4 and 3.5% wt. NaCl solutions. The SEM investigations carried out on the eroded weldment surface show glimpses of erosion mechanisms such as shallow and deep ploughing, oxide cracks, ridges and valleys, scale formation at some areas attributing to sulphide deposition. The corrosion that occurred on the weldment surface tested under acidic conditions is relatively high compared to the alkaline conditions. The reinforcement form factor is the most preferable weld bead characteristic to obtain better erosion and corrosion resistant weldments in the investigated pipe material.

Assessment of a Wind Turbine Blade Erosion Lifetime Prediction Model with Industrial Protection Materials and Testing Methods

Leading edge protection (LEP) coating systems are applied to protect turbine blade edges from rain erosion. The performance of a LEP system is assessed in an accelerated rain erosion test (RET) as a metric for industrial application, but these tests are expensive. Modelling methods are available to predict erosion, based on fundamental material properties, but there is a lack of validation. The Springer model (1976) is analysed in this work to assess it as a tool for using material fundamental properties to predict the time to failure in a rain erosion test. It has been applied, referenced and industry validated with important partial considerations. The method has been applied successfully for erosion damage by wear performance prediction when combined with prior material data from rain erosion test (RET), instead of obtaining it directly from fundamental properties measured separately as Springer proposed. The method also offers accurate predictions when coupled with modified numerical parameters obtained from experimental RET testing data. This research aims to understand the differences between the experimental data used by Springer and the current industry approach to rain erosion testing, and to determine how it may introduce inaccuracies into lifetime predictions of current LEP systems, since they are very different to those tested in the historic modelling validation. In this work, a review of the modelling is presented, allowing for the understanding of key issues of its computational implementation and the required experimental material characterisation. Modelling results are discussed for different original application issues and industry-related LEP configuration cases, offering the reader to interpret the limits of the performance prediction when considering the variation in material fundamental properties involved.

A Novel Framework to Study the Role of Ground and Fumed Silica Fillers in Suppressing DC Erosion of Silicone Rubber Outdoor Insulation

This paper investigates the effect of ground and fumed silica fillers on suppressing DC erosion in silicone rubber. Fumed silica and ground silica fillers are incorporated in silicone rubber at different loading levels and comparatively analyzed in this study. Outcomes of the +DC inclined plane tracking erosion test indicate a better erosion performance for the fumed silica filled composite despite having a lower thermal conductivity compared to the ground silica composite. Results of the simultaneous thermogravimetric and thermal differential analyses are correlated with inclined plane tracking erosion test outcomes suggesting that fumed silica suppresses depolymerization and promotes radical based crosslinking in silicone rubber. This finding is evident as higher residue is obtained with the fumed silica filler despite being filled at a significantly lower loading level compared to ground silica. The surface residue morphology obtained, and the roughness determined for the tested samples of the composites in the dry-arc resistance test indicate the formation of a coherent residue with the fumed silica filled composite. Such coherent residue could act as a barrier to shield the unaffected material underneath the damaged surface during dry-band arcing, thereby preventing progressive erosion. The outcomes of this study suggest a significant role for fumed silica promoting more interactions with silicone rubber to suppress DC erosion compared to ground silica fillers.

Investigation of Internal Erosion Susceptibility of Core Soil from Three Dams

Laboratory tests on internal erosion of cohesionless soils are often performed on cells submitted to a controlled seepage. The cell dimension depends on the grain size of tested soil and must meet the geometric and hydraulic scale requirements as regards to the modeled process. Three specimens collected from different zoned dams in Morocco were characterized for their geotechnical properties and dispersion sensitivity, and then submitted in two different cells to internal erosion (Hole Erosion Test) under controlled seepage. The erosion kinetics was measured, and soil classification was assessed as regards to the useful engineering guidelines. The results showed that specimen dimensions can affect the erosion parameters which are quite different from a cell to another. Even though the derived erosion coefficient values are different from the two testing cells, the classification of the three soils regarding the susceptibility to erosion, using engineering guidelines, indicated that the tested soils fall overall in neighboring erosion classifications. However, the soil involving the lower clay content provided the greatest resistance against internal erosion.