In this exploration, we delve into the intricacies of tension tests performed on various types of steel, including mild steel, tor steel, and high tensile steel. The objective is to uncover essential properties such as Young’s modulus, ultimate strength, and percentage elongation. The tension test involves subjecting a steel rod to tension loads using a Universal Testing Machine (UTM). This article provides a thorough breakdown of the equipment, methodology, and results of the tension test on steel rods.
The UTM, a pivotal apparatus, consists of a loading unit and a control panel. The loading unit, equipped with upper, middle, and lower crossheads, handles the application of tension loads. The control panel facilitates load application through hydraulic pressure, employing a pendulum dynamometer to measure and indicate force on the specimen.
The tension test involves subjecting the specimen to constant tension load while noting the extension within the elastic limit. Key points such as yield point, breaking point, and ultimate point are meticulously recorded. Subsequently, stress and strain calculations are executed, leading to the derivation of critical parameters such as modulus of elasticity, yield stress, ultimate stress, and percentage elongation.
The initial step involves cleaning the steel rod specimen and marking the gauge length, determined by a specific formula.
An assumed tensile stress value guides the calculation of the maximum expected load capacity of the rod. This, in turn, helps establish the range set in the UTM.
Careful handling involves fitting the specimen to the top base, adjusting valves, and locking jaws securely.
The right valve controls load application, while the left valve releases the load. Crucial load points, including the yield and ultimate points, are identified.
Upon surpassing the ultimate stress, necking occurs, resulting in a significant reduction in the cross-sectional area of the steel rod.
A stress-strain graph is plotted using recorded values, depicting the material’s behavior under tension.