Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 2020

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Parameters optimization of MAG welding for enhancing the mechanical properties and buckling behaviour of welded steel

Alwan A. H., Mahmood N. Y.

Journal of Achievements in Materials and Manufacturing Engineering

2020

Vol. 99, nr 1

5--13

Purpose: The influence of metal active gas welding variables, including current, wire feeding speed and gas flow rate on the ultimate tensile strength and critical buckling load of steel (St.24) and the optimized welding conditions were discussed. Design/methodology/approach: The experimental steps are firstly designing the experiments, secondly conducting the mechanical tests, thirdly analysing the results through Minitab 16 and finally determining the optimum welding parameters. Confirmation tests of the optimized variables were validated. Findings: ANOVA approach manifested that the significant effect of welding variable on the tensile strength was the gas flow rate, while the current was on the critical buckling load. The results are confirmed and given the optimum values. Research limitations/implications: The influence of MAG welding variables (current, wire feeding speed and gas flow rate) on the tensile and buckling strengths of steel will be investigated in order to avoid the failure of many welded assemblies in the structures due to the buckling, in addition to reduce the requirement of long time and high cost to produce such assemblies. Therefore, it is necessary to find a solution to encounter the difficulties in their welding process. Practical implications: The major challenge was how to reduce the time and cost beside gaining the optimum properties through the designed experiments. Originality/value: The results may be helpful to design any welded joints in machine frames, structural steel connections and crane structures at the optimum condition.

Buckling and bending properties of aluminium plate with multiple cracks

Mohmmed J. H., Mahmood N. Y., Ali M., Zainulabdeen A. A.

Archives of Materials Science and Engineering

2020

Vol. 106, nr 2

49--58

Purpose: In this paper, the bending strength and buckling stability of (AA 7075-T6) aluminium plate weakened by many transverse cracks, which located at different positions, subjected to concentrated loads applied at the ends were analysed. Design/methodology/approach: Numerical modelling and calculation by the finite element method (ANSYS Package), for the critical load of bending and compression panel were estimated. Findings: It found that the variation of the critical stress in bending and buckling is proportional to the crack conditions (no. of crack and location). In general, the critical load in bending and buckling decreases with increasing the crack number in structure. Research limitations/implications: For both bending and buckling, two transverse cracks on one face of plate is more stable than two transverse cracks on opposite faces. Practical implications: In addition, many experimental tests were carried out by using an INSTRON test machine to obtain the buckling critical loads, where the experimental results were compared with the ones of the finite element method. Furthermore, bending strength was calculated theoretically for the cracked panel. Originality/value: Comparison between the experimental and numerical (FE based model) data and between the theoretical and nu-merical (FE based model) data for buckling and bending strength respectively indicate the precise and the simplicity of the developed models to determine the critical loads in such cases.