Analysis Of Aluminum Alloys Research Articles

Analysis of aluminum alloys on a Polyvac E980 (Hilger Analytical) atomic emission spectrometer modified with a multi-channel analyzer of emission spectra (MAES)

A Polyvac E980 (Hilger Analytical) photoelectric vacuum optical emission spectrometer has been modified with a multichannel analyzer of emission spectra (MAES). The line of argon supply to the spark stand has been completely renewed. A precision mass flow controller with a microprocessor control unit has been installed to adjust the argon supply for different operation modes and fix the current values with the possibility of saving data for each spectrum. The microprocessor control unit coordinates the operation of the control lines and interrupts the operation of the spark generator when the stand is open or argon is absent. The modified vacuum spark spectrometer, originally designed for the analysis of iron-based alloys, has become suitable for determining the composition of non-ferrous alloys. Analytical programs have been developed for the rapid spectral analysis of AK12M2 and AK9ch aluminum alloys. The main methodological difficulty of the analysis is attributed to the necessity of monitoring high concentrations of silicon, copper, and iron along with the content of calcium impurity in the same sample. Calcium has a negative effect on the quality of castings, thus making the possibility of Ca determination an important motivation for the modification. After the preparatory work and the construction of calibration curves, the short-term and long-term repeatability of the results of spectral analysis of standard samples of aluminum alloys has been studied on the modified spectrometer. The results completely meet the standard requirements for determining the composition of aluminum alloys.

Fatigue Life Analysis of Aluminum Alloy Notched Specimens under Non-Gaussian Excitation based on Fatigue Damage Spectrum

In this study, a non-Gaussian excitation acceleration method is proposed, using aluminum alloy notched specimens as a research object and measured acceleration signal of a certain airborne bracket, during aircraft flight as input excitations, based on the fatigue damage spectrum (FDS) theory. The kurtosis and skewness of the input signal are calculated and the non-Gaussian characteristics and amplitude distribution are evaluated. Five task segments obey a non-Gaussian distribution, while one task segment obeys a Gaussian distribution. The fatigue damage spectrum calculation method of non-Gaussian excitation is derived. The appropriate FDS calculation method is selected for each task segment and the acceleration parameters are set to construct the acceleration power spectral density, which is equivalent to the pseudo-acceleration damage. A finite-element model is established, the notch stress concentration factor of the specimen is calculated, the large mass point method is used to simulate the shaking table excitation, and a random vibration analysis is carried out to calculate the accelerated fatigue life. The simulation results show that the relative error between the original cumulative damage and test original fatigue life is 15.7%. The shaking table test results show that the relative error of fatigue life before and after acceleration is less than 16.95%, and the relative error of test and simulation is 24.27%. The failure time of the specimen is accelerated from approximately 12 h to 1 h, the acceleration ratio reaches 12, and the average acceleration ideal factor is 1.125, which verifies the effectiveness of the acceleration method. It provides a reference for the compilation of the load spectrum and vibration endurance acceleration test of other airborne aircraft equipment.

Bending cyclic behavior and scatter-band analysis of aluminum alloys under beneficial and detrimental conditions through high-cycle fatigue regime

This article presents the bending fatigue behavior and the scatter-band analysis of aluminum alloys under beneficial conditions of nano-clay-particles and heat-treating, compared to detrimental conditions of the mechanical stress and the corrosion. Moreover, the sensitivity analysis was also done on the stress level, the pre-corrosion phenomenon, the addition of nano-particles and applying the heat treatment on the high-cycle bending fatigue lifetime of the aluminum-silicon alloy. For this objective, gravity and stir-casting processes were done for aluminum alloy and nano-clay-composite specimens and then, standard samples were machined from initial casted cylinders. Furthermore, rotary fatigue tests were performed under cyclic bending loadings, through the high-cycle fatigue regime. Some samples were pre-corroded in the sulfuric acid for 200 hours. Based on the sensitivity analysis on experimental data by the Minitab software, the obtained results indicated that the stress level was the effective parameter on the fatigue lifetime. The meaningful regression model was calculated and calibrated on the logarithmic scale of the fatigue lifetime. Then, the second sensitive parameter was demonstrated as the pre-corrosion, which caused a significant degradation of fatigue properties in the material. The last-ranked factor was related to nano-particles for the beneficial effect on the improvement of the high-cycle fatigue lifetime. The scatter-band analysis illustrated that nano-particles and heat-treating changed the scattering behavior of experimental data.

Effect of die geometry on thermal fatigue analysis of aluminium alloy (A02240) dies of low melting point alloys casting using pressure die casting process

ABSTRACT There are several constituents that cause die fractures in the die casting process. Several features can be managed to a certain level with the help of specialists like geometry experts, production specialists and engineers. In the die casting procedure, the main loading feature is the fluctuating nature of thermal conditions; therefore, the effect of further forces is comparatively negligible. In order to achieve cost-efficient manufacturing for die casting, different metals' essentiality of die’s high operational life is required. Expenditure on die substitution is very high and it increases the manufacturing period. Failure of die can be recognised when fracture line appears on the die surface and it grows during further manufacturing. The main objective of this work is to find out thermal fatigue analysis of aluminium alloy (A02240) dies during the pressure die casting procedure. The location of cooling channels from base is varying (0.5–5 mm). Thus, we get six geometry models for every material. By using ANSYS workbench 17.1, we find three major factors related to this analysis: work temperature distribution, fatigue life and normal stresses generated in dies.

Numerical analysis of aluminum alloy fused coating process

Aiming at the difficulties in the additive manufacturing process of aluminum alloy, the aluminum alloy fused coating process with arc preheating is proposed. A three-dimensional transient numerical model is established based on the finite difference method. The evolution process of melt flow and spreading is studied, and the interaction effects between the molten fluid and the driving forces were analyzed. The effect of the different distance between the nozzle and the tungsten electrode on the coating process is computed. It is found that when the distance is less than 8 mm, the substrate cannot directly absorb the energy of the arc and the preheating effect of the front heat source is gradually lost. The aluminum alloy melt spread is blocked and spread sideways, and the contour profile of the coating layer begins to become irregular. When the distance is greater than 14 mm, spheroidization occurs at the position of the starting end of the coating layer. Through the analysis of the dimensionless numbers, it is found that in the early stage of the fused coating process, the heat lost by heat conduction in the molten pool is more than that of convection and the influence order of partial driving forces is surface tension > Lorentz force > buoyancy.

基于激光诱导击穿光谱与径向基函数神经网络的铝合金定量分析

基于激光诱导击穿光谱与径向基函数神经网络的铝合金定量分析

Welding deformation analysis of aluminum alloy and steel sheet metal parts based on resistance spot welding

Auto-body lightweight is becoming an important trend of energy saving and emission reduction. Various materials assembled together would be used to fabricate the auto-body to satisfy this demand. However, the assembly dimensional quality is difficult to be controlled in the real processing due to the huge differences in material properties. Therefore, it is necessary to control and analyze the welding deformation of aluminum alloy and steel. In this work, the orthogonal design experiment has been adopted to analyze the welding deformation of steel–aluminum sheet parts. Subsequently, the response surface model is proposed to establish the relationship between welding deformation and welding parameters by finite element analysis, which is verified by physical experiments again. Meanwhile, the anti-deformation method is also used to decrease the assembly deformation successfully. And the case of Z-shaped planes is applied to further illustrate the proposed method of this work. Finally, the results show that both the methods have a good simulation effect and a high prediction accuracy for the assembly dimensional quality.

远程激光诱导击穿光谱定量分析铝合金中的微量元素

远程激光诱导击穿光谱定量分析铝合金中的微量元素

3次元アトムプローブによるアルミニウム合金中のナノ組織解析

3次元アトムプローブによるアルミニウム合金中のナノ組織解析

Analysis of aluminum alloys by resonance-enhanced laser-induced breakdown spectroscopy: How the beam profile of the ablation laser and the energy of the dye laser affect analytical performance

In resonance-enhanced laser-induced breakdown spectroscopy, the sample was ablated by a laser pulse and the expanding plume was photoresonantly rekindled by a dye laser pulse. By sampling aluminum alloys for Mg, Pb, Si, and Cu, we showed that for the ablation step, Gaussian beams gave 2 to 3× better signal-to-noise ratio (SNR) than non-uniform beams. For the rekindling step, if no further sample destruction was allowed, dye laser pulses that intercepted the plume transversely gave 6 to 12× higher SNR than the longitudinal case. By combining Gaussian beams and transverse rekindling, the mass limit-of-detection for Mg was about 100 amol while non-resonant analysis was 10× more destructive. Sub-monolayer of oxides grown on laser-cleaned aluminum surfaces was detected by monitoring the AlO emissions of rekindled plumes; without resonant enhancements, they were not detectable no matter how destructive was the analysis. Time resolved studies showed that the Gaussian beam produced less dispersed plumes and that a stronger dye laser beam directed transversely heated up a bigger plume mass without over-heating the plume core. The analyte emissions were sustained while the continuum background remained low.

Distortion Analysis of Aluminum Alloy for Sheet Metal Forming after Solution Treatment

The sheet metal parts play important role in aero structures. Due to the requirement of strength and constraint of weight in aircraft, the aluminum alloy is widely used in sheet metal forming parts. Most of sheet metal parts form the contour in O-condition, and then solution treat to improve the strength and mechanical property. The deformation of sheet metal parts usually takes place after the heating cycle and quenching into the water or solution. The straightening operation will apply to corrective the contour of parts. Thus, the non-value added operation would increase the production cost. By using statistical methodology to analysis deformation data of sheet metal parts, this study use Cause-Effect Analysis to find the relation between deformation and relative factors, such as material, thickness and contour. The results of this analysis can provide an efficient and economical approach for the designer, process planner, and technician in manufacturing the sheet metal parts.

Limiting state analysis of aluminum alloys under asymmetric tension-compression cycling

The authors address the problem of cyclic strength analysis of aluminum alloys under static and cyclic loading. The calculations are performed by means of limiting state models representing all of the known forms of limit stress diagrams.

Finite element modelling analysis of aluminium alloy 2017 thermal/fluid multiple fields during a single roll stirring process

The single roll stirring (SRS) process was described by finite element modelling analysis for different process parameters. An ANSYS program was adopted to calculate thermal/fluid fields during the manufacture of 2017 semisolid aluminium alloy by SRS process. The effects of process parameters on thermal/fluid fields were investigated. Process parameters of manufacturing semisolid aluminium alloy 2017 by SRS process were optimised.

Quantitative Analysis of Aluminium Alloys using SIMS

Abstract A quantitative method for analysis of aluminium alloys using secondary-ion mass spectroscopy has been tested. The sensitivity factor, Sx/Al, for several elements (x) was determined using homogenised Al materials. Also other Al alloys were analysed using almost identical instrumental conditions. It was found that since the materials investigated contained much Fe and Mg, they contributed with molecular interferences when measuring Ti and Ni. The results showed that while keeping constant the analytical parameters, it was possible to use sensitivity factors Sx/Al with a good accuracy for quantification of the elements which were mainly solved in the matrix. The results indicated that the metal was still slightly inhomogeneous in several elements even after annealing at 550°C for one week. Another important factor is that the emission spectrometer has a high relative standard deviation for the analysis below 5 wt.ppm. This resulted in variations in the calculated sensitivity factor for elements like...

On-line control of heat extraction during thermal analysis of aluminium alloys

Thermal analysis is a non-destructive and quantitative technique used to assess the quality of liquid metal prior to casting. Conventional thermal analysis is carried out by pouring a relatively small sample of the melt into a sampling cup. The liquid metal is then allowed to solidify, and its temperature is recorded as a function of time. One of the shortcomings associated with this method is that the physical and thermal characteristics of the sampling cup in any one given test determine the effective cooling rate. Moreover, the method is a batch operation which is difficult to automate and to computerise. To overcome these shortcomings, a new technique of performing thermal analysis has been devised. This new technique, which is based on heat pipe technology, is in-situ, semi-continuous, easy to use, dependable, and most importantly, capable of performing thermal analysis tests at controlled and variable cooling rates throughout the entire solidification process. In the present paper, the characteristics of the new system, as well as the technique of controlling the cooling rate (heat extraction) during thermal analysis of aluminium alloys are described.

Surface treatment and analysis of aluminum alloy at room temperature with titanium-nitride films by dynamic mixing

Titanium-nitride films were prepared on aluminum alloy (Al-11 wt.% Si) plates at room temperature by simultaneous ion bombardment and metal vapor deposition (dynamic mixing) using a high current ion source. The films were analysed by means of Auger electron spectroscopy and scanning electron microscopy. The results were compared with those made by metal vapor deposition and ion plating. The process of impurity inclusion in the titanium-nitride films made by dynamic mixing is discussed. Titanium films deposited by electron beam evaporation had high levels of oxygen impurities. However, when the same film was simultaneously bombarded by nitrogen ions, the levels of oxygen impurities decreased in the deposited titanium-nitride films.

Determination of nitrogen, oxigen, fluorine, phosphorus, sulfur and chlorine in aluminium alloys by means of neutron activation

N, O, F, P, S, Cl can be mixed with aluminium during electrolysis, alloying operations and surface treatments. These elements allow changes in mechanical properties. We have adapted separation methods to neutron activation analysis of aluminium alloys down to the sub—ppm level. N, F, Cl, determinations need distillation. S and P separations are based on liquid extraction. O determination is carried out by instrumental method. Tracers and inactive carriers are used for separation study. Clearning of the surface is performed if necessary. 14 MeV neutron activation is applied to nitrogen, oxygen and fluorine determination. The sensitivity is about 200 imp/min/mg. Reactor neutron activation is performed for phosphorus, sulfur and chlorine analysis. The detection level is 0.1 μg/g. Interesting differences of N, O, F, and Cl contents are observed for Al−Zn or Al−Cu alloys in the range 0.1–10 μg/g.

Spectral analysis of aluminum alloys in the Soviet Union

Spectral analysis of aluminum alloys in the Soviet Union

The analysis of aluminium alloys by atomic absorption spectroscopy with special reference to the determination of chromium and zirconium

The analysis of aluminium-base alloys for silver, copper, magnesium, zinc, chromium, and zirconium by atomic absorption spectroscopy is described. The use of hot flames (nitrous oxide-acetylene) allows improvements to earlier procedures for such analyses. Sensitivities are increased, interferences reduced, and the determination of more refractory elements, e.g. Cr and Zr, becomes possible. Hollow-cathode lamps with greatly increased resonance-line intensities are used for the determination of chromium and zirconium.

The X-Ray Diffraction Measurement of Residual Stresses in Aluminum Alloys

AbstractThis paper presents the theoretical and practical aspects of measuring residual stresses by X-ray diffraction with emphasis on the analysis of aluminum alloys. The theoretical considerations of radiation) beam geometry, and peak location will be discussed in regard to establishing optimum analysis techniques. The precision and reproducibility of this technique have been investigated so that results can be applied accurately. The approach, however, is basically a practical one, with the intent of studying residual stress systems as they affect engineering applications. Residual stress systems produced by thermal and mechanical treatments have been determined and the effect of treatment modifications and variations on the resultant stress system have been analyzed. The effect of operational variables such as time and temperature on the developed stress system are shown. From this, the merits of a particular treatment can be determined with respect to its intended application.Analysis of solution heat-treated and quenched 2014 aluminum has shown a significant effect of the quench temperature on the resultant residual stress system. The results obtained from shot-peening this alloy are presented, as well as the effect of time and temperature on the shot-peened stress gradient.