Tensile and flexural behaviour of steel materials used in the construction of crop processing machines
Elijah A. Alhassan, David A. Olasehinde, A Musonda, Oluwaseye Micheal Odeniyi
Abstract
Abstract This experiment investigated the mechanical properties of mild steel, galvanized iron and stainless steel when subjected to tensile and flexural loading. Work pieces of 54 samples were prepared having a gage length of 30 mm for material thicknesses of 1, 1.5 and 2 mm which was replicated three times. Properties such as peak force at break, elongation at break, stress, and strain of the materials were studied using a testometric M500-100AT Universal Testing Machine (UTM). The peak force obtained for mild steel was 2495.43, 4643.33 and 6215.67 N for 1, 1.5 and 2 mm respectively. The elongations of mild steel were 48.88, 54.77 and 56.11 mm for 1, 1.5, and 2 mm respectively. For stainless steel tensile strength analysis, the peak forces obtained are 9486.66, 9558.00 and 9522.33 N for 1, 1.5 and 2 mm respectively. The deformation of the material occurred at similar loads having stresses of 535.20, 583.51 and 486.88 N/mm2 for the thicknesses investigated. Similarly, the stress-strain relationship of the material ranged from 10131.20 N/mm 2 to 12757.33 N/mm 2 while the elongation amount of strain it can withstand before failure are 30.54, 38.64 and 47.74 mm. The bending strength for mild steel both at peak and at break increased as the thickness increases. Bending strength at peak are 364.50, 378.33 and 381.87 N/mm 2 for 1, 1.5 and 2 mm respectively with 2 mm expectedly showing the greatest bending strength. Also, for stainless steel, the deflection of the different length of stainless steel at peak increased as the length increased unlike for mild steel with a reverse case. The deflection at break decreased as the length of the materials increases. The bending strength at peak and the bending modulus increased as the length of the material was increased, while at break the reverse was the output. From this investigation, it can be observed that stainless followed by mild steel have higher tensile and yield strength than galvanized iron. This explain the wide applications of stainless steel and mild steel in various crop processing machines constructions and other engineering uses that require high strength.