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This study aims to solve the problem of weld quality inspection, for the aluminum alloy profile welding structure of high-speed train body has complex internal shape and thin plate thickness (2–4 mm), the conventional nondestructive testing method of weld quality is difficult to implement.

In order to solve this problem, the ultrasonic creeping wave detection technology was proposed. The impact of the profile structure on the creeping wave detection was studied by designing profile structural test blocks and artificial simulation defect test blocks. The detection technology was used to test the actual welded test blocks, and compared with the results of X-ray test and destructive test (tensile test) to verify the accuracy of the ultrasonic creeping wave test results.

It is indicated that that X-ray has better effect on the inspection of porosities and incomplete penetration defects. However, due to special detection method and protection, the detection speed is slow, which cannot meet the requirements of field inspection of the welding structure of aluminum alloy thin-walled profile for high-speed train body. It can be used as an auxiliary detection method for a small number of sampling inspection. The ultrasonic creeping wave can be used to detect the incomplete penetration welds with the equivalent of 0.25 mm or more, the results of creeping wave detection correspond well with the actual incomplete penetration defects.

The results show that creeping wave detection results correspond well with the actual non-penetration defects and can be used for welding quality inspection of aluminum alloy thin-wall profile composite welding joints. It is recommended to use the echo amplitude of the 10 mm × 0.2 mm × 0.5 mm notch as the criterion for weld qualification.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

The paper aims to use the finite volume method widely used in computational fluid dynamics to avoid the serious remeshing and mesh distortion during aluminium profile extrusion processes simulation when using the finite element method. Block-structured grids are used to fit the complex domain of the extrusion. A finite volume method (FVM) model for aluminium extrusion numerical simulation using non-orthogonal structured grids was established.

The influences of the elements ' nonorthogonality on the governing equations discretization of the metal flow in aluminium extrusion processes were fully considered to ensure the simulation accuracy. Volume-of-fluid (VOF) scheme was used to catch the free surface of the unsteady flow. Rigid slip boundary condition was applied on non-orthogonal grids.

This paper involved a simulation of a typical aluminium extrusion process by the FVM scheme. By comparing the simulation by the FVM model established in this paper with the ones simulated by the finite element method (FEM) software Deform-3D and the corresponding experiments, the correctness and efficiency of the FVM model for aluminium alloy profile extrusion processes in this paper was proved.

This paper uses the FVM widely used in CFD to calculate the aluminium profile extrusion processes avoiding the remeshing and mesh distortion during aluminium profile extrusion processes simulation when using the finite element method. Block-structured grids with the advantage of simple data structure, small storage and high numerical efficiency are used to fit the complex domain of the extrusion.

This paper aims to develop a specific type of mobile nonrigid support friction stir welding (FSW) robot, which can adapt to aluminum alloy trucks for rapid online repair.

The friction stir welding robot is designed to complete online repair according to the surface damage of large aluminum alloy trucks. A rotatable telescopic arm unit and a structure for a cutting board in the shape of a petal that was optimized by finite element analysis are designed to give enough top forging force for welding to address the issues of inadequate support and significant deformation in the repair process.

The experimental results indicate that the welding robot is capable of performing online surface repairs for large aluminum alloy trucks without rigid support on the backside, and the welding joint exhibits satisfactory performance.

Compared with other heavy-duty robotic arms and gantry-type friction stir welding robots, this robot can achieve online welding without disassembling the vehicle body, and it requires less axial force. This lays the foundation for the future promotion of lightweight equipment.

The designed friction stir welding robot is capable of performing online repairs without dismantling the aluminum alloy truck body, even in situations where sufficient upset force is unavailable. It ensures welding quality and exhibits high efficiency. This approach is considered novel in the field of lightweight online welding repairs, both domestically and internationally.

The purpose of this paper is to find an efficient way by using finite volume method (FVM) to simulate the aluminum alloy profile extrusion processes.

By assuming isotropic conditions, the hot aluminum material is described as a non‐linear Newtonian fluid material. Semi‐implicit method for pressure‐linked equations algorithm is used to calculate the physical fields, and the dynamic viscosity is updated then. Volume of fluid method and moving grid method are also used for unsteady flow to catch the free surface of the material and the moving bound.

FVM model in this paper is an accurate and efficient method for the numerical simulation of aluminum profile extrusion processes. Compared with finite element method software, FVM model is both memory and CPU efficient.

Provide theoretical reference for sound extrusion process and die designs, which are the key factors to produce desirable products in industrial production.

The paper finds an efficient way to introduce the FVM in computational fluid dynamics field into the simulation of the steady and unsteady aluminum alloy profile extrusion processes. It provides a reference for people who are interested in FVM and extrusion processes.

Based on the DVS1608-2011 and IIW-2008 and BS EN15085-3 standards, the stress state grade of welded joints of aluminum alloy EMU (Electric Multiple Units) body was studied.

First, the calculation methods of the stress state grade of aluminum alloy welded joints analyzed by DVS1608-2011 and IIW-2008 standards were studied, and the two methods were programmed by the APDL language of ANSYS. Then, the finite element model of aluminum alloy EMU body was established; the static strength calculation result of the body was compared with the test result, and the error is basically within 10%. Finally, under the acceleration fatigue load provided by BS EN12663 standard, the fatigue analysis was carried out on the welded joint of the vehicle body, and the stress state of the welded joint of the vehicle body was studied according to IIW-2008 and DVS1608 standards, respectively.

The results show that the assessment method based on IIW-2008 standard is more rigorous, and the maximum stress factor of the longitudinal weld between the side beam and the side wall is 0.811; the position occurs in the area where the longitudinal weld of the side beam and the side wall is close to the lower door angle.

The stress state is medium, and the rest of the weld stress states are low.

The purpose of this paper is to compare corrosion behavior of a modified multilayer material with Cu before and after brazing process.

Sea water acidified accelerated tests (SWAATs), potentiodynamic polarization tests and scanning electron microscopy were used to study the corrosion behavior and macro/micro structures. Results indicate that the corrosion mechanisms of the sheets before and after brazing process are completely different.

The un-brazed material is uniform corrosion, while the brazed material has a high sensitivity to localized corrosion and loses cathodic protection to the core. It is found that brazing process causes copper transition from the core alloy into eutectic phases in the cladding, leading to higher E_corr and different potential distribution compared with those of un-brazed materials.

For the modified multilayer material after brazing, there are two stages of corrosion. First, corrosion attack takes place along eutectic phases in the cladding material, and then core alloy dissolves by forming a galvanic couple with the nobler residual cladding.

This paper aims to investigate the sources of variation in aluminum profiles hot extrusion process for the purpose of process capability improvement at National Aluminum and Profiles Company (NAPCO) in Palestine. The critical-to-quality characteristics (CTQ) have been determined as base variables to measure the process capability.

The DMAIC (Define, Measure, Analyze, Improve, and Control) Lean Six Sigma (LSS) approach has been adopted to conduct this study. More specifically, historical data analysis and PARETO charts have been employed. The defects' root causes have been determined using the cause-and-effect diagram and decision matrix. A course of suggested actions has been established to help in improving extrusion process capability. Minitab-18 software was used for conducting inferential statistical analysis. A case study considering a geometry CTQ of D3 dimension of bottom sash aluminum profiles 4,332 was selected for analysis.

The results indicated a reduction in DPMO from 89,649 to 15,659, sigma level was improved from 2.84 to 3.65, process yield was improved from 91.04% to 98.43% and cost was reduced from U$75,972 to U$13,250.9 (i.e. a saving of U$62,721). Studying and improving the sigma level of the extrusion process would yield fewer defective products and consequently fewer customer complaints. A validation process which has been conducted during the year 2019 showed a consistent improvement that aligns with the first stage of improvement made on October 1, 2018.

This study focuses on only one critical quality characteristic (CTQ), namely, a geometry CTQ of D3 dimension of bottom sash aluminum profiles 4,332 produced by NAPCO was selected for analysis.

This study would be useful for researchers and practitioners to improve the process capability in aluminum profiles manufacturing industries in general and hot extrusion processes in particular.

Many previous studies on applying LSS-DMAIC methodology have been conducted in aluminum industries in developed countries. According to the literature, it is highly recommended to have more case studies of applying LSS-DMAIC in different industries in developing countries. NAPCO is the only aluminum manufacturing plant in Palestine that hotly extrudes and coats aluminum profiles. Hence, the present study is the first of its kind in NAPCO and in Palestine. Projecting the assessment of the impact of process improvement opportunities and capability analyses into monetary measures are also innovative.

Aluminum alloys are applicable in marine and aero fields. Alloys AA5083 and AA6061 are aluminum alloys with different chemical and physical properties. Combination of two dissimilar materials could result in enhanced strength. Generally, dissimilar aluminum alloy joint is made by friction stir welding (FSW) to achieve improved physical properties compared with the parent alloys. The purpose of this research is to develop a new FSW dissimilar material with enhanced properties using AA5083 and AA6061 alloys.

In this research, FSW joint was made for butt joint configuration using AA5083 and AA6061 aluminum alloys. Cylindrical pin with threaded profile was used to perform the joint. The tool tilting angle was maintained as constant, and the tool rotational speed and the welding speed were varied. Wear performance and mechanical strength of the joint were analyzed.

The results revealed that the increase of tool rotational speed led to poor wear performance, whereas increase of welding speed showed a better wear performance. Further, the prepared joint was analyzed for different wear parameters such as sliding velocity and applied load. The results displayed that the increase of sliding velocity exhibited low wear rate and the increase of load showed high wear rate.

This work is original and deals with the wear performance of AA5083–AA6061 joint at different tool rotational and welding speeds.

This study aims to investigate and model interrelationships between process parameters, geometrical profile characteristics and mechanical properties of industrially extruded aluminum alloys.

Statistical design of experiments (DOE) was applied to investigate and model the effects of eight factors including extrusion ratio, stem speed, billet-preheat temperature, number of die cavities, quenching media (water/air), time and temperature of artificial aging treatment and profile nominal thickness on four mechanical properties (yield strength, ultimate tensile strength, percent elongation and hardness). Experiments were carried out at an actual extrusion plant using 8-in. diameter billets on an extrusion press with 2,200 ton capacity.

Main factors and factor interactions controlling mechanical properties were identified and discussed qualitatively. Quantitative models with high prediction accuracy (in excess of 95%) were also obtained and discussed.

The obtained results are believed to be of great importance to researchers and industrial practitioners in the aluminum extrusion industry.

All practical and relevant parameters have been used to model all important mechanical properties in a collective manner in one study and within actual industrial setup. This is in contrast to all previous studies where either a partial set of parameters and/or mechanical properties are discussed and mostly under limited laboratory setup.