Material Properties Of Aluminum Alloy Research Articles

ENHANCEMENT IN MICROSTRUCTURAL CHARACTERISTICS AND MECHANICAL PROPERTIES OF A6082-BASED MMCS VIA YTTRIA STABILIZED ZIRCONIA INCORPORATION AND T6 HEAT TREATMENT

This study investigates the impact of Yttria Stabilized Zirconia (YSZ) and T6 heat treatment on the mechanical and microstructural properties of A6082-based Metal Matrix Composites (MMCs) prepared using the conventional stir casting route. A6082 is widely used in various industrial applications due to its excellent physical, structural and functional properties with good corrosion resistance. YSZ with superior mechanical and thermal properties that can enhance the strength and wear resistance of aluminium-based composites. T6 heat treatment is a widely adopted technique to improve the material properties of aluminium alloys. The results of this study indicate that the T6 heat treatment significantly refines the grain structure of the composites, resulting in improved hardness and tensile values compared to untreated samples. Mechanical properties are also enhanced by YSZ's integration into the composites, with a 9wt.% YSZ addition to the matrix alloy leading to a noticeable improvement in hardness for both the untreated and treated composites. The tensile parameters show a similar trend, with a gain in Ultimate Tensile Strength and Yield Strength up to 6wt.% YSZ addition, after which the findings follow a downtrend (at 9wt.%). The results of this research show that A6082/YSZ composites subjected to T6 heat treatment have great promise as a high-performance material.

Sustainable laser metal deposition of aluminum alloys for the automotive industry

In the last few years, there has been increasing interest in the processing of aluminum alloys using additive manufacturing (AM) processes. Thanks to their properties, aluminium alloys are extensively used in aerospace, rail, and automotive industries. Laser metal deposition (LMD), among the AM processes, can manufacture complex features as well as reinforcement structures on pre-existing complex parts. The work performed within the SAMOA project aims to expand the knowledge of the material properties of aluminum alloys when the LMD process is performed under atmospheric conditions. Both common alloys (AlSi10Mg, AlSi1Mg) and AM-specific alloys (AM205 and AlSi1Mg + 1 wt. %Zr) were analyzed and compared. Results show significantly lower amounts of internal defects and higher mechanical properties in AM-specific alloys. This database of mechanical properties will be used to design, simulate, and fabricate reinforcement structures on car frames to enhance their crash resistance and increase vehicle security. Moreover, to reduce material waste, the SAMOA project focuses also on the effects of powder recycling by analyzing both chemical and physical changes in the powder. The higher concentration of oxygen and hydrogen was separately analyzed by artificially increasing their concentration by heat treating AlSi10Mg powder. Results showed similar processability with a reduction in UTS of −31.4% and an increased elongation at fracture of +112.5%. Recycled powder, on the other hand, could not be easily collected, sieved, and reused since the identified physical and chemical changes of the powder lower its processability.

Cyclic hardening/softening experimental data in nano-clay-composite and aluminum alloy under high-temperature strain-controlled loading

Abstract This article presents cyclic hardening/softening behaviors (experimental data) of the heat-treated aluminum-matrix nano-clay-composite (AlSi_N_HT6), compared to those of the piston aluminum alloy (AlSi) under strain-controlled loading. For such an objective, standard samples were fabricated by gravity and stir-casting methods. Low-cycle fatigue experiments were carried out under different strain amplitudes (0.20–0.45%) and at various temperatures (25–300°C). Obtained results implied that no obvious change was observed on material properties of aluminum alloy by reinforcements, but a decrement was observed due to increasing the temperature. Results also indicated that the increase of the temperature from 25°C to 200°C has changed the cyclic behavior of both materials (AlSi_N_HT6 and AlSi) from hardening to softening. Moreover, the temperature effect was more significant than the total strain amplitude influences in cyclic behaviors.

Creep-Fatigue Experiment and Life Prediction Study of Piston 2A80 Aluminum Alloy.

In order to improve the reliability and service life of vehicle and diesel engine, the fatigue life prediction of the piston in a heavy diesel engine was studied by finite element analysis of piston, experiment data of aluminum alloy, fatigue life model based on energy dissipation criteria, and machine learning algorithm. First, the finite element method was used to calculate and analyze the temperature field, thermal stress field, and thermal–mechanical coupling stress field of the piston, and determine the area of heavy thermal and mechanical load that will affect the fatigue life of the piston. Second, based on the results of finite element calculation, the creep–fatigue experiment of 2A80 aluminum alloy was carried out, and the cyclic response characteristics of the material under different loading conditions were obtained. Third, the fatigue life prediction models based on energy dissipation criterion and twin support vector regression are proposed. Then, the accuracy of the two models was verified using experiment data. The results show that the model based on the twin support vector regression is more accurate for predicting the material properties of aluminum alloy. Based on the established life prediction model, the fatigue life of pistons under actual service conditions is predicted. The calculation results show that the minimum fatigue life of the piston under plain condition is 2113.60 h, and the fatigue life under 5000 m altitude condition is 1425.70 h.

Design of aluminium alloy beams at elevated temperatures

The material properties of aluminium alloys could be affected significantly as temperature rises. The present study aims to investigate the behaviour of aluminium alloy beams at elevated temperatures using finite element analyses. The newly developed numerical model was validated against a total of eight square hollow section beams subjected to three-point bending tests at elevated temperatures. The validated model was used to generate 120 numerical results in the parametric study. Three key parameters were considered, including cross-section slenderness ranging from 8 to 38, temperatures ranging from 24 °C to 600 °C and two aluminium alloys (6061-T6 and 6063-T5). Thus, a data pool containing a total of 128 experimental and numerical results was formed. The appropriateness of the design rules in the American Aluminium Design Manual, the Australian/New Zealand Standard, Eurocode 9 and the continuous strength method (CSM) for aluminium alloy beams at elevated temperature are assessed against the newly generated data pool. In comparison, the design strengths predicted by the four design methods are generally conservative, whereas the CSM approach is found to be the most accurate and consistent throughout the full temperature range. Additionally, reliability analysis has also been conducted to evaluate the reliability level of the aforementioned design methods for aluminium alloy beams at elevated temperatures.

Material properties of normal and high strength aluminium alloys at elevated temperatures

Aluminium alloys are being used widely in multiple engineering applications. However, the material properties of aluminium alloys could change significantly at high temperatures. This paper studied the mechanical properties of normal strength aluminium alloy 6063-T5 and high strength aluminium alloy 6061-T6 at elevated temperatures. Tensile tests were conducted at room temperature (24 °C) and high temperatures up to 600 °C. Both steady temperature state tests and transient temperature state tests were used. The yield stress (i.e., 0.2% proof stress), the ultimate stress, the Young's modulus, and the ultimate strain were determined from tests. The measured material properties at different temperatures are compared with the predictions by the American and European specifications. A series of unified equations for calculating the reduction factors of the material properties at high temperatures are proposed herein; they are found to yield more accurate reduction factors for aluminium alloys.

Crashworthiness behavior of aluminum profiles with holes considering damage criteria and damage evolution

ABSTRACT In this paper the commercial finite element software Abaqus was employed to analyze the effect of mechanical discontinuities on the crashworthiness performance of aluminum profiles. Special emphasis was placed on material damage and its evolution during a crash event. The discontinuities were located at different heights on two opposite walls of aluminum profiles. During the crash simulations, the profiles were subjected to axial impact loads using a 500 kg rigid body striker with an initial velocity of 10 m/s. The ductile material properties of aluminum alloys were considered using the shear, ductile and Muschenborn–Sonne Forming Limit Diagram (MSFLD) damage initiation criteria in the discrete models. In order to model the progressive failure and removal of finite elements, damage evolution option was applied. In all cases, the implementation of discontinuities shows a reduction of peak load (P max ) of up to 4.74% with respect to a profile without discontinuities. In the same way, an increase in energy absorption (E a ) and crush force efficiency (CFE) of 7% and 12.69% respectively, was observed. It was found that the implementation of discontinuities increases the crashworthiness performance of the aluminum profiles. Moreover, the best location for the discontinuities was at the top of the walls of the structure. Following this finding, a typical application in automotive crashworthiness design was demonstrated successfully.

Automatic optimization of localized heat treatment for Al-Si-Mg alloys

Material properties of aluminium alloys can usually be achieved by a heat treatment and quenching procedure. In case that only local strengthening is needed, a local heat treatment and quenching strategy could be an option to the energy intensive, time consuming and costly treatment of the whole part. One of the essential problem using a local strengthening procedure is the lack of knowledge about suitable process parameters. Therefore, a multiple criteria optimization approach with local strengthening as target function was set up, whereby the material constitution was calculated based on the precipitation evolution during local heat treatment and cooling. By automatically varying the exposure time and laser power, a series of process simulations was performed to find adequate process parameters for the sufficient local strengthening of the alloy.

Correlation between Nuclear and Electrical Methods for Estimating the Activation Enthalpy of Defect Formation in 2024 Alloys

The Objective of this Research Was to Investigate the Use of a Sensor System to Monitor Continuously the Defect Formation Response of Heat-Treatable Aluminum Alloys. the System Continuously Monitors a Material Property, Resistivity, which Is Indicative of the Quenching Process. such Studies Will Allow us to Gain Active Control of the Aging Process and Hence the Material Properties of Aluminum Alloys.

Effects of transverse welds on aluminum alloy columns

This paper investigates the effects of transverse welds on aluminum alloy columns. The materials of the specimens were 6063-T5 and 6061-T6 heat-treated aluminum alloys. Various coupon tests were performed to obtain the non-welded and welded material properties of aluminum alloys. An accurate and reliable finite element model (FEM) was used for the simulation of aluminum alloy stub columns of square and circular hollow sections (SHS, CHS) in this study. The stress–strain relationships obtained from the coupon tests were incorporated in the FEM. A parametric study was conducted that included 48 columns of different section shapes with and without transverse welds at the ends of the columns. This study focused on the effects of transverse welds on column strengths with respect to the section slenderness. Hence, the parametric study was performed on stub columns of SHS and CHS in constant column length. The European Code for aluminum structures uses the heat-affected zone (HAZ) softening factor to consider the weakening effects of transverse welds on column strength. The HAZ softening factors obtained from the parametric study were compared with the corresponding values specified in the European Code. HAZ softening factors were proposed in this study.

비대칭 다단 두께 변화를 고려한 결정입 제어 반용융 알루미늄 소재의 캐스팅에서 사출속도가 액상편석에 미치는 영향

Recently, in the field of automobile industry, to solve the problem of reducing the weight of automobile for the improvement of fuel efficiency and the protection of environment, the aluminum alloy parts have been substituted for the steel parts. However, the aluminum alloy does not have as good mechanical property as the steel part. To improve the mechanical property, the semi-solid die casting process is performed to make automobile parts. In the fabrication of semisolid material the control of the liquid segregation is very important to improve the material properties of aluminum alloy. In the present paper we examine the influence of the liquid segregation by the injection conditions in the semi-solid die casting has been investigated.

Hybrid models for aluminium alloy properties prediction

This paper describes a novel modelling approach based on a hybrid structure developed for predicting the material properties of aluminium alloys for different deformation conditions. The model is based on physical equations and neuro-fuzzy models. The paper describes the methodology for developing the hybrid model and the validation process which covers a wide range of alloys, treatment temperatures and deformation conditions (e.g. plane strain compression (PSC) tests, strain rate).

Material Properties of Aluminum Alloy for Accurate Draw-Bend Simulation

The main objective of this paper is to simulate springback using a combined kinematic/isotropic hardening model. Material parameters in the hardening model are identified by an inverse method. A three-point bending test is conducted on 6022-T4 aluminum sheet. Punch stroke, punch load, bending strain, and bending angle are measured directly during the tests. Bending moments are then computed from these measured data. Bending moments are also calculated based on a constitutive model. Material parameters are identified by minimizing the normalized error between two bending moments. A micro genetic algorithm is used in the optimization procedure. Stress-strain curves are generated with the material parameters found in this way, which can be used with other plasticity models. ABAQUS/Standard, which has the combined isotropic/kinematic hardening model, is used to simulate draw-bend of 6022-T4 aluminum sheet. Absolute springback angles are predicted very accurately.

High Pressure Treatment Technique and Modification in Material Properties of Aluminum Alloys

High Pressure Treatment Technique and Modification in Material Properties of Aluminum Alloys