A356 Alloy Research Articles

Investigation of Mechanical Properties of AL-7SI With 6 WT% of 40- and 90-Micron Size Boron Carbide Metal Matrix Composite

To create and evaluate the mechanical behaviour of B4C-reinforced A356 alloy metal composites that are 6 wt. % and range in size from 40 to 90 microns. Method: By using the liquid melt stir cast process, an alloy called A356 with 6 wt. % B4C reinforced composites was created. SEM and EDS were used to characterise the microstructure of these produced composites. According to ASTM standards, mechanical characteristics such as hardness and tensile strength were assessed. Findings: The extensive dispersion of B4C particles in the A356 matrix was demonstrated by a SEM of A356 alloy with 6 wt. % of B4C composites. The A356 alloy matrix's EDS signals verified the presence of B4C particles. The hardness increased by 28.6%, ultimate strength by 26%, and yield strength by 44.4 percent with a little loss in ductility with the addition of 6 wt. % of B4C particles. Novelty: Aerospace-grade aluminium alloy A356 is often utilised in industrials. B4C particles with a size range of 40 to 90 microns were included into advanced metal composites to assist reduce weight. The choice of A356 alloy and B4C reinforcement was made strategically to meet the demanding conditions of mining operations. The results indicate a clear potential for improving the efficiency and overall performance of mining equipment.

Corrosion and thermal fatigue characteristics of TiC-xNi coatings by high-frequency induction-heated combustion synthesis in A380 alloy melt

Corrosion and thermal fatigue characteristics of TiC-xNi coatings by high-frequency induction-heated combustion synthesis in A380 alloy melt

Enhanced mechanical properties of Sr-modified Al–Mg–Si alloy by thermo-mechanical treatment

Abstract In this study, the effect of thermomechanical treatments applied to strontium-modified A360 alloy on the microstructure and mechanical properties of the alloy was investigated. Optical microscopy, XRD, and SEM were employed to examine the microstructural properties, while tensile and hardness tests were conducted on the samples to evaluate the mechanical properties. It was observed that the strength values increased as the deformation amount increased, and subsequently, optimum conditions (tensile strength and ductility) were determined after the subsequent aging treatment. Following cold deformation, dendritic structure shifted towards the direction of deformation along with the eutectic silicon structure. After aging, it was found that the dendritic structure transformed into equiaxed grains at certain temperature. The highest tensile strength of 383 MPa was achieved in the sample with a deformation amount of 70 %. In this case, the ductility value was 2.85 %. Subsequently, the optimum conditions after aging were determined as 160 °C & 4 h, resulting in a tensile strength of 341 MPa and ductility of 3.62 %.

Effect of Sr-Ti-B and T6 Heat Treatment on Microstructure and Mechanical Properties of Sand Cast A360 Alloy

Effect of Sr-Ti-B and T6 Heat Treatment on Microstructure and Mechanical Properties of Sand Cast A360 Alloy

An In Situ Study of Short Crack Initiation and Propagation During Fatigue Testing of a Hot Isostatically Pressed Al-7%Si-0.5%Mg (A357-T6) Alloy Specimen.

A hot isostatically pressed specimen of the A357 alloy in T6 condition has been tested for fatigue performance in situ. During testing, multiple small cracks were observed during the first cycle, both in proximity to and far from the stress concentration. These cracks have competed to form a propagating crack, forming multiple crack paths initially. Once the propagating crack has been established, it has chosen paths from multiple cracks that have opened around the tip to grow further. All small cracks observed to open have been attributed to bifilms, i.e., liquid metal damage. It is imperative to develop processes that minimize liquid metal damage to enhance the fatigue performance of aluminum alloy castings.

Effect of pre-deformation on microstructure and mechanical properties of a fine-grained 2A97 alloy.

This study investigates the effect of pre-deformation by cold rolling after solution annealing on the microstructure and properties of the fine-grained Al-Li alloy 2A97. Electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize grain boundaries, dislocations, precipitates and calculate their contribution to strength. It is found that the changes in precipitation behavior predominantly account for the enhanced tensile properties observed in the deformed alloys, where yield and tensile strengths are increased by 85 MPa and 63 MPa, respectively. The peak-aged samples without pre-deformation are mainly strengthened by the T1 phase, δ'/θ'/δ' composite and σ phase. In contrast, deformation of 10 % prior to aging facilitates the precipitation of the T1 and lath-like S phases while concurrently inhibiting the precipitation of the σ phase and δ'/θ'/δ' composite phases. In addition, for fine-grained alloys, low-angle grain boundaries induce the precipitation of the finer T1 phase compared to the T1 phase located inside the grain, which contributes to the good performance of 2A97 alloy.

Effect of Stable and Transient Cavitation on Ultrasonic Degassing of Al Alloy

Cavitation is a critical phenomenon for improving melt quality in casting processes by reducing hydrogen porosity, and it can be classified into two major types based on bubble dynamics, stable and transient cavitation. In this study, the relationship between stable and transient cavitation and the degassing efficiency of A356 alloy was evaluated. Cavitation intensity was quantified based on the Karman vortices method, and the measured cavitation intensities were processed through FFT transformation to analyze the acoustic spectra. The line spectrum and continuous spectrum were characterized separately to quantify stable and transient cavitation in distilled water. Negligible change in stable cavitation was observed, while transient cavitation increased with amplitude. On the other hand, both stable and transient cavitation increased proportionally with frequency. By employing the characterized cavitation indices, the effects of stable and transient cavitation on ultrasonic degassing of A356 were assessed. It was confirmed that transient cavitation was the dominant factor in the degassing before the degassing efficiency reached a steady state. This study clearly demonstrates that optimizing frequency to enhance transient cavitation is a more effective approach for increasing intensity and, consequently, improving degassing efficiency.

Assessment and Improvement of Melt Quality of Recycled Secondary A357 Alloy by Application of the High Shear Melt Conditioning (HSMC) Technology

In addition to impurities in recycled aluminum alloys, non-metallic inclusions are a significant factor that deteriorates the material’s castability and final mechanical properties. This, therefore, restricts the ability to transition from a primary to secondary aluminum alloy. In this study, the cleanliness of the recycled A357 alloy was evaluated through non-metallic inclusions’ characterization, hydrogen content measurement, fluidity test, and casting defects identification. The non-metallic inclusions generated during the recycling process of A357 alloy were collected by the pressurized melt filtration technique. All of the inclusion types collected during filtration were examined and identified by analytical scanning electron microscopy (SEM). Extra additions of up to 2 wt.% swarf in these secondary A357 alloys were designed to simulate highly contaminated alloys. Different to the conventional melt cleaning technologies that mainly focus on complete removal of inclusions, this study developed a novel approach that combines the removal of easily removeable inclusions while preserving well-dispersed inclusions that do not adversely affect the mechanical properties. This study demonstrates that high shear melt conditioning (HSMC) technology can achieve well-dispersed small non-metallic inclusions, low hydrogen content, improved fluidity, and fewer casting defects. As a result, the melt quality of the recycled A357 alloys has achieved a quality comparable to that of primary A357 alloy.

Implications of incorporating CrFeNiTiZn high-entropy alloy on the tribomechanical and microstructure morphology behaviour of A356 composites processed by friction stir processing

Abstract This study investigated the impact of incorporating a CrFeNiTiZn High Entropy Alloy (HEA) into the A356 aluminum matrix through the friction stir processing (FSP) technique. The CrFeNiTiZn HEA, renowned for its compositional complexity and high-performance potential, was incorporated into the A356 alloy with different weight percent combinations to enhance its mechanical and tribological characteristics. The results revealed a refined microstructure characterized by solid solution phases and potential intermetallic compound formation due to the HEA addition for A356/2 %Cr2 %Fe2 %Ni2 %Ti2 %Zn composition. Strong interfacial bond strength was also observed among the matrix and reinforcement particles for the A356/2 %Cr2 %Fe2 %Ni2 %Ti2 %Zn composition. The number of grains was found to be about 1820.34 (average grain size is 686 µm) for A356/2 %Cr2 %Fe2 %Ni2 %Ti2 %Zn processed composite with FSP per square inch at 500 magnifications. The A356/2 %Cr2 %Fe2 %Ni2 %Ti2 %Zn composite exhibited improved tensile strength (35.70 %) and hardness (63.33 %) after the addition of 2 %Cr2 %Fe2 %Ni2 %Ti2 %Zn into A356 alloy, attributed to the strengthening effect of HEA particles. Furthermore, wear resistance is notably enhanced, likely due to the synergistic effects of the HEA’s inherent hardness and the modified microstructure.

Research on the microstructure and mechanism of high content Sn modified A356 alloy

The effect of Sn alloying on the casting structure of A356 aluminium alloy, especially on the morphology of eutectic silicon, is investigated in detail. With the increase of Sn content, the eutectic silicon gradually changed from sheet to fine coral, and the α-Al dendrites are significantly refined. Within the modified eutectic silicon, there are high density crossed stacking faults located in the <111>Si direction. The analysis reveals that these stacking faults are caused by the segregation of Al-Mg-Sn atomic clusters on the {111}Si growth plane, which hinders the stacking of Si atoms on the growth step and induces lateral growth of eutectic silicon. Mg2Sn phase formed by Sn and Mg enrichment will preferentially nucleate and grow in the {111}Si growth layer, which will also hinder the macroscopic growth of eutectic silicon. In this paper, the phenomenon of stacking faults induced by Al-Mg-Sn atomic clusters leading to the eutectic modification is proposed and investigated for the first time.

Investigation of the effect of Fe on flexural strength of A356 alloy

Investigation of the effect of Fe on flexural strength of A356 alloy

THE EFFECT OF HEAT-TREATMENT ON THE MECHANICAL PROPERTIES OF EXPANDED GLASS PARTICLE/A356 SYNTACTIC FOAM

This research investigates the manufacturing of metal syntactic foams (MSFs) using a packed bed of porous (2-2.8 mm) expanded glass (EG) within an A356 alloy matrix. To this end, the counter-gravity infiltration casting technique is employed to manufacture the specimens. The density of the MSFs ranges from 1.05 to 1.17 g/cm3, making it one of the lowest densities foams, attributed to the filler particles' low bulk density. The study investigates the influence of T6 heat treatment on the mechanical properties and microstructural characteristics of the manufactured MSFs. The mechanical properties of the MSFs are characterized under quasi-static compressive loads at 1 mm/min. After heat treatment, the compression test results indicate a significant enhancement in most mechanical properties. Compression strength and plateau stress are approximately doubled compared to as-cast foams for samples with similar densities. While energy absorption of the MSFs triples in heat-treated conditions. These improvements are attributed to changes in the matrix microstructure due to thermal treatment. Microstructural analysis reveals that Si particles, initially sharp and continuous within inter-dendritic boundaries, become blurry and discontinuous through spheroidization after thermal treatment. This hinders crack growth in the cell wall and mitigates the effects of casting defects and the columnar dendritic structure. The majority of mechanical properties in both heat-treated (HT) and as-cast (AC) foams exhibited an increase in density due to an increase in the matrix fraction. However, plateau end strain and energy absorption efficiency demonstrated an independent effect of heat treatment and density.

Microstructural, mechanical, and wear properties of ultrasonic assisted stir casted A356 Alloy/AlN composite

The ultrasonic-assisted stir-casting method has effectively prepared A356 alloy/AlN composites. The ultrasonic treatment and integration of AlN particles are shown to greatly enhance the mechanical and wear characteristics of the matrix via grain refinement. By incorporating 9 vol.% of AlN reinforced particles, the average grain size of A356 alloy was decreased from 36 μm to 10 μm. Additionally, the hardness and tensile strength experienced a respective rise of 60.6% and 32%. With an increase in the volume percentage of AlN particles, it is found that both the wear rate and the friction coefficient decreased. It is also observed that the A356 alloy displayed severe wear, whereas the composites exhibited moderate wear.

Formation of seaweed morphology and enhancing mechanical properties of an A356 alloy by directional solidification

In the present work, regular dendrite and seaweed pattern are produced by controlling the crystal orientation during directional solidification of an A356 aluminium alloy. These morphologies and growth orientation were investigated by electron backscatter diffraction (EBSD), and the results showed that the seaweed pattern mainly prevailed under the (100)[011] orientation. At the same time, the effects of seaweed pattern in the properties of A356 alloy were analysed by room temperature tensile test. It was found that the elongation and toughness of the samples reached 20 % and 36 J/m3, respectively, for the seaweed; 13 % and 24 J/m3, respectively, for the regular dendrites; and 8 % and 14 J/m3, respectively, for the cast ingot. Compared with the regular dendrite samples, the seaweed pattern obtained relatively excellent elongation and toughness. By using scanning electron microscopy (SEM), it is found that the distribution of eutectic silicon particles in seaweed morphology sample is more refined and uniform, which is the main reason for these enhancements.

Mechanical Properties and Tribological Study of Bottom Pouring Stir-Cast A356 Alloy Reinforced with Graphite Solid Lubricant Extracted from Corn Stover

The present work epitomises extracting the graphite (Gr) solid lubricant from the corn stover. The extracted Gr was incorporated as reinforcement in the A356 alloy (Al-7Si), and the effect of the Gr particles on the mechanical and tribological properties was investigated. In spite of this, the input process parameters for the dry sliding wear test at room temperature against the EN31 steel disc were optimised through ANOVA analysis. The fabricated A359—X wt% (X = 0, 2.5, 5, 7.5) composite through bottom pouring stir casting techniques was analysed microstructurally by using XRD and FESEM analysis. The micro Brinell hardness and tensile strength were investigated per ASTME10 and ASTME8M standards. A wear test was performed for the composite pins against the EN31 steel disc according to ASTM G99 specifications. The XRD analysis results depict the presence of carbon (C), aluminium (Al), and silicon (Si) in all the wt% of the Gr reinforcement. However, along with the elements, the Al2Mg peak was confirmed for the A356—7.5 wt% Gr composite and the corresponding cluster element was confirmed in FESEM analysis. The maximum micro Brinell hardness of 92 BHN and U.T.S of 123 MPa and % elongation of 7.11 was attained at 5 wt% Gr reinforcement due to uniform Gr dispersion in the A356 alloy. Based on the ANOVA analysis, the optimal process parameters were obtained at 20 N applied load, 1 m/s sliding velocity, and 1000 m sliding distance for the optimal wear rate of 0.0052386 g/km and 0.364 COF.

Study on the influence of trace elements H on the properties of A356 aluminum alloy

Abstract The vacuum melt purification refining technology can significantly reduce the content of hydrogen elements in alloy melts and prevent defects such as hydrogen-induced pinholes. This article investigates the effect of hydrogen content on the chemical composition, mechanical properties, and structural defects of A356 alloy melt by using vacuum melt purification refining technology to reduce the hydrogen content in A356 alloy melt. The experimental results show that: 1) there is basically no loss of chemical elements during the vacuum melting process; 2) The use of vacuum refining and purification control technology can control the hydrogen content inside the melt to be ≤ 0.10ml/100g; 3) The effect of H content on the metallographic structure of A356 alloy is not significant, but it has a certain improvement on the tensile strength at room temperature, but the increase is ≤ 5%.

Friction stir processing: A thermomechanical processing tool for high pressure die cast Al-alloys for vehicle light-weighting

This study uses friction stir processing (FSP) for thermomechanical processing of high-pressure die-casting (HPDC) to modify microstructure and improve mechanical properties. FSP is carried out on two different HPDC aluminum alloys: (a) general-purpose, high-iron, HPDC A380 alloy and (b) premium quality, low-iron HPDC Aural-5 alloy in thin wall, flat plate geometry. Subsequent mechanical testing shows ∼30 % and ∼65 % enhancement in yield strength and tensile ductility. In addition, FSP leads to ∼10 times improvement in fatigue life for A380 alloy and ∼70 % improvement in fracture toughness for Aural-5 alloy. These findings emphasize the capability of FSP to modify the microstructure of HPDC Al-alloys-based structural components so that they can demonstrate a good combination of strength, ductility, fracture toughness, and high fatigue properties for long-term durability and reliability.

Microstructural and mechanical Characterization of friction stir processed A356 alloy

Microstructural and mechanical Characterization of friction stir processed A356 alloy

Effect of Fly Ash and Silica Particles on Mechanical and Thermal Properties of A-356 alloy

Arsalan, Feroz Shah, Quaid Jamal, Bilal Islam, Aizaz Ahmad Khan

Copper Slag as an Alternative to Silica Sand for A356 Alloy Casting-Feasibility Study

Copper Slag as an Alternative to Silica Sand for A356 Alloy Casting-Feasibility Study